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Interesting Excerpts
The following excerpts are from articles or books that I have recently read. They caught my interest and I hope that you will find them worth reading. If one does spark an action on your part and you want to learn more or you choose to cite it, I urge you to actually read the article or source so that you better understand the perspective of the author(s).
Algae Suggest Eukaryotes Get Many Gifts of Bacteria DNA

[These excerpts are from an article by Elizabeth Pensini in the 1 February 2019 issue of Science.]

      Algae found in thermal springs and other extreme environments have heated up a long-standing debate: Do eukaryotes—organisms with a cell nucleus—sometimes get an evolutionary boost in the form of genes transferred from bacteria? The genomes of some red algae, single-celled eukaryotes, suggest the answer is yes. About 1% of their genes have foreign origins, and the borrowed genes may help the algae adapt to their hostile environment….

      Many genome studies have shown that prokaryotes—bacteria and archaea—liberally swap genes among species, which influences their evolution. The initial sequencing of the human genome suggested our species, too, has picked up microbial genes. But further work demonstrated that such genes found in vertebrate genomes were often contaminants introduced during sequencing.

      …any such transfers only occurred episodically—early in the evolution of eukaryotes, as they internalized the bacteria that eventually became organelles such [as] mitochondria or chloroplasts….

In Hot Water

[These excerpts are from an article by Warren Cornwall in the 1 February issue of Science.]

      …The data, collected by research trawlers, indicated cod numbers had plunged by 70% in 2 years, essentially erasing a fishery worth $100 million annually. There was no evidence that the fish had simply moved elsewhere. And as the vast scale of the disappearance became clear, a prime suspect emerged: “The Blob.”

      In late 2013, a huge patch of unusually warm ocean water, roughly one-third the size of the contiguous United States, formed in the Gulf of Alaska and began to spread. A few months later, Nick Bond, a climate scientist at the University of Washington in Seattle, dubbed it The Blob. The name, with its echo of a 1958 horror film about an alien life form that keeps growing as it consumes everything in its path, quickly caught on. By the summer of 2015, The Blob had more than doubled in size, stretching across more than 4 million square kilometers of ocean, from Mexico’s Baja California Peninsula to Alaska’s Aleutian Islands. Water temperatures reached 2.5°C above normal in many places.

      By late 2016, the marine heat wave had crashed across ecosystems all along North America’s western coast, reshuffling food chains and wreaking havoc. Unusual blooms of toxic algae appeared, as did sea creatures typically found closer to the tropics….Small fish and crustaceans hunted by larger animals vanished. The carcasses of tens of thousands of seabirds littered beaches. Whales failed to arrive in their usual summer waters. Then the cod disappeared.

      The fish “basically ran out of food,” Barbeaux now believes. Once, he didn’t think a food shortage would have much effect on adult cod, which, like camels, can harbor energy and go months without eating. But now, it is “something we look at and go: ‘Huh, that can happen.’”

      Today, 5 years after The Blob appeared, the waters it once gripped have cooled, although fish, bird, and whale numbers have yet to recover. Climate scientists and marine biologists, meanwhile, are still putting together the story of what triggered the event, and how it reverberated through ecosystems. Their interest is not just historical.

      Around the world, shifting climate and ocean circulation patterns are causing huge patches of unusually warm water to become more common, researchers have found. Already, ominous new warm-patches are emerging in the North Pacific Ocean and elsewhere, and researchers are applying what they've learned from The Blob to help guide predictions of how future marine heat waves might unfold. If global warming isn’t curbed, scientists warn that the heat waves will become more frequent, larger, more intense, and longer-lasting. By the end of the century, Bond says, “The ocean is going to be a much different place.”

      …The Blob was spawned, experts say, by a long-lasting atmospheric ridge of high pressure that formed over the Gulf of Alaska in the fall of 2013. The ridge helped squelch fierce winter storms that typically sweep the gulf. That dampened the churning winds that usually bring colder, deeper water to the surface, as well as transfer heat from the ocean to the atmosphere—much like a bowl of hot soup cooling as a diner blows across it. As a result, the gulf remained unusually warm through the following year.

      But it took a convergence of other forces to transform The Blob into a monster. In the winter of 2014-15, winds from the south brought warmer air into the gulf, keeping sea temperatures high. Those winds also pushed warm water closer to the coasts of Oregon and Washington. Then, later in 2015 and in 2016, the periodic warming of the central Pacific known as El Nino added more warmth, fueling The Blob’s growth. The heat wave finally broke when La Nifia—El Nino’s cool opposite number—arrived at the end of 2016, bringing storms that stirred and cooled the ocean….

      Krill—tiny shrimp that, like copepods, are a key food for many fish—felt the heat, too. In 2015 and 2016, as The Blob engulfed the coasts of Washington and Oregon, the heat-sensitive creatures vanished from biologists’ nets.

      As the base of the food chain crumbled, the effects propagated upward. One link higher, swarms of small fish that dine on copepods and krill—and in turn become food for larger animals—also became scarce as warm waters spread. On a remote island in the northern gulf, where scientists have tracked seabird diets for decades, they noticed that capelin and sand lance, staples for many bird species, nearly vanished from the birds' meals. In 2015, by one estimate, the populations of most key forage fish in the gulf fell to less than 50% of the average over the previous 9 years….

Democracy’s Plight

[These excerpts are from an editorial by Rush Holt in the 1 February 2019 issue of Science.]

      Scientists work with a deep sense that their quest for reliable knowledge leads somewhere—that following the evidence and excluding bias help to make sense of the world. It may be a slow process, and interactions in the scientific community are not without friction and false steps, yet scientists are devoted to the quest because they observe that it works. One can make sense of the world. Einstein famously said, “the eternal mystery of the world is its comprehensibility,” and scientists understand that evidence-based scientific thinking leads to this comprehension. Scientists could do a better job of sharing this powerful insight.

      …Observers speak of “truth decay,” dismissal of expertise, and neglect of evidence. Collectively, these are problems of enormous importance because they threaten democracy itself. Democracy is at risk when it becomes simply a contest of fervently held opinions or values not grounded in evidence. When one opinion is as good as another—each asserted as strongly, and even as deceptively, as possible—democracy cannot survive. Society is drowning in a sea of unmoored opinons and values. Democracy requires a citizenry that is informed, as well as engaged. We must find an opening to reinforce among citizens a renewed appreciation for evidence. Approaching an understanding of the actual state of things is what science does well.

      In the United States, the public's approval and trust in science are relatively strong compared with other institutions, a finding that has been observed in public surveys for decades. Here, then, may be an opening. Can scientists share the admired successes of science in a manner that leads citizens to embrace for themselves the essence of science? This essence of science is to demand evidence at every turn and to discard ideas when they are shown not to comport with the evidence. This thinking is not reserved solely for scientists, and one need not be an expert to demand evidence. Given the public's respect for science and science’s reverence for evidence, can the public be moved to demand and embrace evidence for themselves? This connection seems logical—we need to make it feasible. Can scientists achieve what normal civic education has not achieved? There is no time to waste in finding this out.

From Competition to Collaboration

[These excerpts are from an op-ed article by Giovanni Camanni in the 25 January 2019 issue of Science.]

      It was just like any other morning. I was at the bus stop, on my way to the lab where I was a post-doctoral fellow. But as I watched the people around me—headphones dangling from their ears, eyes cast down, unsmiling faces—something began to stir inside me. They looked unhappy. And, I realized, I was one of them. Suddenly, I could no longer continue with my work life. I turned around, went back to my flat, and booked a one-way ticket to fly home the next morning. I didn’t know how long I would be away or what would come next. All I knew was that, even though I loved science and research, what I had been doing wasn’t working.

      Over the years, as I dealt with the pressures of finishing my Ph.D. and securing and starting my post-doc, I had grown more competitive. To prove that I was a valuable researcher, I pushed myself to be the first to generate sensational results and to publish in high-impact journals. Those who could have been collaborators became rivals I resented.

      But the effect of this competitive streak was exactly the opposite of what I had hoped for. The pressure became overwhelming. When I encountered scientific problems, I thought I had to solve them myself instead of asking for help. I began to feel alone and lost. I became less and less productive. But the culture of academia—prizing competition and individual successes above all else—seemed to reinforce my approach. I was sure that this was not the right time to show any insecurities, so I persevered.

      That day at the bus stop, I hit my breaking point. The race had to end….

      Three months after I left so suddenly, I was prepared to go back to work. I was excited to get back to the science that I loved, and I now had a foundation to be more open with my colleagues. I understood that we all struggle sometimes, and that vulnerability and collaboration can be more powerful than competition. It doesn’t have to be a zero-sum game.

      The first days were difficult. I had naively thought that, right away, everything would be different. But as soon as I was back in that workplace, I felt the stirrings of that old competitiveness. I focused on maintaining my new perspective and being patient as I readjusted. With a bit of time, I understood that, although the place and position were the same, I had changed. I hadn't just accepted my vulnerability; I had embraced it and opened up about it to my colleagues.

      As a result, collaboration has replaced competition. Working with others and seeking help doesn’t diminish my value or contributions; it means we can all win. Now, when I encounter problems in my work, I frequently discuss them with colleagues, knowing that considering multiple points of view often leads to solutions. I have become more productive. Working relationships are now genuine human ones. I no longer feel like one of the lonely, unhappy people at the bus stop.

Light Skin May Be Legacy of Native American Ancestors

[These excerpts are from an article by Lizzie Wade in the 25 January 2019 issue of Science.]

      Walk down a busy street in most Latin American cities today and you’ll see a palette of skin colors from dark brown to sepia to cream. For 500 years, people have assumed this variation comes from the meeting and mixing of Native Americans, Europeans, and Africans during colonial times and later. People with lighter skin are thought to have more European ancestry, whereas those with darker skin are taken to have more Native American or African ancestry—and are often targeted for discrimination.

      Now, a new study of the genes of more than 6000 people from five Latin American countries undercuts the simplistic racial assumptions often made from skin color. An international team discovered a new genetic variant associated with lighter skin found only in Native American and East Asian populations. That means that in Latin America, lighter skin can reflect Native American as well as European ancestry….

      Latin America is fertile ground for such studies. People there often have Native American, European, and African ancestors, and because Native American populations are closely related to those from East Asia, researchers can also spot East Asian variants in Latin American genomes….

      …People at high latitudes in Europe and East Asia seem to have independently evolved lighter skin to produce vitamin D more efficiently with less sunlight….

      The larger lesson…is the pitfalls of a Eurocentric view "Our study shows that going beyond Europeans one can find additional genes, even for well-studied traits. Clearly the bias towards Europeans has led to a restricted view of human diversity."

Where to Find Fantastic Beasts at Sea

[These excerpts are from an article by Nicholas D. Pyenson in the 25 January 2019 issue of Science.]

      The biggest predators in the oceans captivate us for good reasons: Sharks, billfishes, whales, and penguins have big appetites, range over large distances, and have achieved similar body forms from vastly different starting points on the tree of life. Evolutionary convergences among large marine predators are also more than skin deep; those with ancestries on land, such as marine mammals and seabirds, have independently evolved an array of molecular and tissue specializations for maximizing oxygen and warmth. Beyond these fantastic traits, marine predators also possess large body sizes and trophic linkages that make them ecologically important consumers in marine food webs….

      Macroecologists who study marine predators have long known that convergences in form do not yield similar ecological distributions over geographic space. Most marine mammal species occur at higher latitudes, whereas sharks and fishes are found closer to the equator. Endothermic marine mammals are also most plentiful in polar and temperate seas. This latitudinal distribution contrasts with that of nearly every other marine animal group, which shows peaks in equatorial to temperate seas. Why the difference?...a possible answer: A fundamental asymmetry in metabolism gives endotherms an advantage when hunting in colder, more prey-rich waters.

      …The basic distribution maps show startling gaps in top predator occupancy across the globe. For example, there is a lack of marine mammals in the Indo-Australian Archipelago, despite this region being an epicenter for marine biodiversity….

      Explaining this geographic pattern requires revisiting the models that describe the cost-benefit trade-offs of top predators feeding on their prey. On first principles alone, individual endothermic predators maintain consistent metabolism across latitudes, whereas the metabolism of ectotherms plummets in colder waters, which would affect relative foraging performance. Scaling up to the ecosystem level, where prey production is relatively uniform, each endothermic and ectothermic predator species should have strongly differential consumption rates across latitudes—all driven by water temperature as a primary structuring factor….

Oldest Images of Dogs Show Hunting, Leashes

[These excerpts are from an article by David Grimm in the 17 November 2018 issue of Science.]

      Carved into a sandstone cliff on the edge of a bygone river in the Arabian Desert, a hunter draws his bow for the kill. He is accompanied by 13 dogs, each with its own coat markings; two animals have lines running from their necks to the man's waist.

      The engravings likely date back more than 8000 years, making them the earliest depictions of dogs, a new study reveals. And those lines are probably leashes, suggesting that humans mastered the art of training and controlling dogs thousands of years L earlier than previously thought….

      The hunting scene comes from Shuwaymis, a hilly region of northwestern Saudi Arabia where seasonal rains once formed rivers and supported pockets of dense vegetation….

      Starting about 10,000 years ago, hunter-gatherers entered—or perhaps returned to—the region. What appear to be the oldest images are thought to date to this time and depict curvy women. Then about 7000 to 8000 years ago, people here became herders, based on livestock bones found at Jubbah; that's likely when pictures of cattle, sheep, and goats began to dominate the images. In between—carved on top of the women and under the livestock—are the early hunting dogs: 156 at Shuwaymis and 193 at Jubbah. All are medium-sized, with pricked up ears, short snouts, and curled tails—hallmarks of domestic canines. In some scenes, the dogs face off against wild donkeys. In others, they bite the necks and bellies of ibexes and gazelles. And in many, they are tethered to a human armed with a bow and arrow.

      …the engravings may not be as old as they seem. To confirm the chronology, scientists will need to link the images to a well-dated archaeological site—a challenge, she says, because “the archaeological record in this region is really spotty.”

Beyond Plastic Waste

[These excerpts are from an editorial by Dame Ellen MacArthur in the 17 November 2018 issue of Science.]

      With more than 8 million tons of plastic entering the ocean each year, humanity must urgently rethink the way we make and use plastics, so that they do not become waste in the first place.

      Cheap, light, and versatile, plastics are the dominant materials of our modern economy. Their production is expected to double over the next two decades. Yet, only 14% of all plastic packaging is collected for recycling after use, and vast quantities escape into the environment. This not only results in a loss of $80 billion to $120 billion per year to the global economy, but if the current trend continues, there could be more plastic than fish by weight in the oceans by 2050.

      Some companies have started changing their habits. Unilever, for example, has promised that by 2025, all its plastic packaging will be fully reusable, recyclable, or compostable in a commercially viable manner. Given that up to a third of all plastic packaging items are too small (such as straws and sachets) or too simplex (such as multimaterial films and take-away coffee cups) to be economically recycled, achieving these commitments will require a great degree of redesign and innovation.

      Such company commitments and innovations are a step in the right direction. But creating a plastics system that works will require collaboration among all participants in the plastics sector….

      …Bans on or charges for single-use shopping bags have, for example, led to rapid reductions in their use in France, Rwanda, and the United Kingdom. A few uncommon types of plastic used in packaging are too expensive to recycle and should be phased out. A science-based approach is needed to replace chemicals such as endocrine disruptors that are found in some plastics and pose a risk to human health.

      Such restrictions need to be complemented by mechanisms that foster innovation. Policy-makers can connect the design of plastic packaging with its collection, sorting, and subsequent reuse, recycling, or composting by supporting deposit-refund schemes for drinks bottles, as in Germany and Denmark, or by requiring producers to consider what happens to their packaging products after use. A useful policy approach is extended producer responsibility (EPA), which makes producers responsible for the entire product life cycle. EPR policies have been introduced in European Union legislation and at the national level for packaging, batteries, vehicles, and electronics. Such policies can support good design and improve the economics of after-use options for packaging materials.

      However, the most potent tool for policy-makers remains the setting of a clear common vision and credible high-level ambitions that drive investment decisions. In the case of plastics, a crucial pillar of such a policy ambition must be stimulating scientific breakthroughs in the development of materials that can be economically reused, recycled, or composted….

Massive Fish Die-off Sparks Outcry in Australia

[These excerpts are from an article by Dennis Normile in the 25 January 2019 issue of Science.]

      Australians knew another long drought was hammering the country’s southeast. But it took a viral Facebook video posted on 8 January to drive home the ecological catastrophe that was unfolding in the Murray-Darling river system. In the footage, Rob McBride and Dick Arnold, identified as local residents, stand knee-deep among floating fish carcasses in the Darling River, near the town of Menindee. They scoff at authorities’ claims that the fish die-off is a result of the drought. Holding up an enormous, dead Murray cod, a freshwater predator he says is 100 years old, McBride says: “This has nothing to do with drought, this is a manmade disaster.” Arnold, sputtering with rage, adds: “You have to be bloody disgusted with yourselves, you politicians and cotton growers.”

      Scientists say McBride probably overestimated the age of the fish. But they agree that the massive die-off was not the result of drought….

      Excessive water use has left river flows too low to flush nutrients from farm runoff through the system, leading to large algal blooms, researchers say. A cold snap then killed the blooms, and bacteria feeding on the dead algae sucked oxygen out of the water, suffocating between 100,000 and 1 million fish. The death of so many individuals that had survived previous droughts is “unprecedented,” says ANU ecologist Matthew Colloff. And with fish of breeding age decimated, recovery will be slow. “But only a bloody fool would put a time frame on that,” Colloff says.

      This wasn’t supposed to happen. In 2012, the national government adopted the Murray-Darling Basin Plan, touted as a “historic” deal to ensure that enough water remained in the rivers to keep the eco-system healthy even after farmers and households took their share….

      The 1-million-square-kilometer Murray-Darling Basin accounts for 40% of Australia’s agricultural output, thanks in part to heavy irrigation. By the early 2000s, water flows in the lower reaches of the basin were just a third of historical levels, according to a 2008 study. During the millennium drought, which started in the late 1990s and lasted for a decade, downstream communities faced water shortages.

      In 2008, the federal government created the Murray-Darling Basin Authority to wrestle with the problem. In 2010, a study commissioned by the authority concluded that farmers and consumers would have to cut their use of river water by at least 3000 but preferably by 7600 gigaliters annually to ensure the health of the ecosystem. Farmers, who saw their livelihoods threatened, tossed the report into bonfires.

      The final plan, adopted as national law in 2012, called for returning just 2750 gigaliters to the rivers, in part by buying water rights back from users….

      Implementation has exacerbated the problems. Since 2012, the federal government has spent AU$6 billion on the plan, but two-thirds has gone to improving irrigation infrastructure, on the premise that efficiency would ease demands on the rivers. Critics say the money would have been better spent on purchasing water rights.

      Grafton says there are also suspicions of widespread water theft; up to 75% of the water taken by irrigators in the northern part of the system is not metered. Farmers are also now recapturing the runoff from irrigated fields that used to flow back into streams, and are increasing their use of ground water, leaving even less water in the system….

      In February 2018, such issues prompted a group of 12 academics, including scientists and policy experts, to issue the Murray-Darling Declaration. It called for independent economic and scientific audits of completed and planned water recovery schemes to determine their effects on stream flows. The group, which included Williams and Grafton, also urged the creation of an independent, expert body to provide advice on basin water management. Young, who wasn't on the declaration, wants to go further and give that body the power to manage the basin’s water, the way central banks manage a country’s money supply, using stream levels to determine weekly irrigation allocations and to set minimum flow levels for every river.

      Before the fish kill, such proposals had garnered little attention. But Young hopes the public outrage will influence federal elections that have to take place by mid-May….

Bearing Witness

[These excerpts are from an article by Douglas Starr in the 25 January 2019 issue of Science.]

      In a St. Louis, Missouri, courtroom last summer, David Egilman testified in a lawsuit filed by 22 women who claimed to have contracted ovarian cancer from exposure to Johnson & Johnson (J&J) baby powder. Like millions of women before them, they had dusted their babies with the powder and used it on themselves thousands of times. They alleged the talc was tainted with asbestos and that exposure to the carcinogenic fiber likely played a role in their cancers.

      Egilman, a professor of family medicine at Brown University who served as a paid expert witness, brought science and medical gravitas to his testimony. He interviewed the women about their frequency and duration of talc use, and he factored in the levels of asbestos that outside scientists had found in samples of talc, which is sometimes mined from formations that also yield asbestos. From those data, he said, he could calculate the women’s doses of the carcinogen, and he argued that their exposure had doubled their risk of ovarian cancer.

      J&J had its own experts, who said the talc was asbestos-free and there was no proof that the product caused cancer. But Egilman’s decisive contribution may have come from his scrutiny of company documents. After examining thousands of pages of internal J&J documents unearthed during the litigation, he and his student researchers concluded that J&J found no asbestos in the talc because its tests were not sensitive enough. He compared the company's methods to trying to weigh a needle on a bathroom scale.

      …(Since the trial, other internal J&J documents have become public, which show the company knew about the asbestos contamination for decades but suppressed the information.)

      Egilman believes corporations have minimized their costs at the expense of their employees’ health and that of the public and the environment—and that recent weakening of regulations has made that problem worse. He sees speaking out in court as a mission. “As a doctor, I can treat one cancer patient at a time,” he explained during a trial last year. “But by being here, I have the potential to save millions.” More broadly, he says corporate money and power have intimidated scientists and corrupted science itself—a concern that has led him into battle not only with corporations, but also with journals that publish what he describes as tainted results.

      In 35 years as an expert witness, he has given depositions and testimony in more than 600 cases of occupational or environmental disease. He has helped win billions of dollars for injured or sick workers or consumers, or for the families of those who have died. By his reckoning, he has earned more than $5 million for such legal work; he says he has donated some of his fees to charities, including a nonprofit he founded to improve health in developing countries.

      Specializing in occupational lung disease, Egilman diagnoses patients and marshals data. But he also digs into corporate records uncovered during litigation, invariably finding memos and studies showing that com-panies knew about industrial hazards long before warning employees or the public….

      Egilman’s sense of mission propels a prodigious work ethic—by his own estimate, he works 100 to 120 hours per week—and some-times emboldens him to act rashly. In 2007, patients were suing Eli Lilly and Company, claiming that its antipsychotic medicine olanzapine (Zyprexa) had caused dramatic weight gain and diabetes. Reviewing company documents as an expert witness for the plaintiffs, Egilman found emails implying Eli Lilly knew of the danger but long tried to play it down. The judge ordered that the documents be kept confidential to protect the company’s proprietary sales and marketing strategies, but Egilman leaked them to a New York Times reporter. “A physician’s oath never says to keep your mouth shut,” Egilman says.

      The court was not amused by that “brazen breach” of protocol. “They could have put me in jail,” Egilman says. To avoid criminal charges, he paid a $100,000 settlement. But after the newspaper story ran, 30 states subpoenaed documents on Eli Lilly's sales and marketing activities, showing the same incriminating behavior. In 2009, it agreed to pay $1.4 billion to settle criminal cbarges and civil suits….

Nuclear Power and Promise

[These excerpts are from a book review by Jacob Darwin Hamblin in the 18 January 2019 issue of Science.]

      Less than a year after the Fukushima nuclear accident in Japan, physicist Gregory B. Jaczko tried to break the “first commandment” of nuclear regulation: Thou shalt not deny a license to operate a reactor. As chairman of the U.S. Nuclear Regulatory Commission (NRC), he knew that the tradition was to encourage doomed applications to be withdrawn. But when one company refused, Jaczko dug in his heels and opposed the license. It turned out to be a futile gesture that the other commissioners opposed. But it was one of many examples, he contends, of the weaknesses in the nation’s top nuclear regulatory body and an exemplar of its obeisance to the nuclear power industry.

      Confessions of a Rogue Nuclear Regulator is one part engrossing memoir and another part seething diatribe, depicting a government agency that routinely caves to industry pressure….

      …The ensuing political fracas convinced Jaczko that the nuclear industry used the NRC as a tool for promoting rather than regulating nuclear power. He believes that a national repository for radioactive waste puts too much responsibility on the taxpayer….

      The answer is to stop producing nuclear waste, argues Jaczko, and indeed stop producing nuclear power at all. He wishes that as chairman, he’d “had the courage to say this, but my courage had its limits.”

      Most of Jaczko’s short book hammers on the theme that industry lobbyists hold sway over the would-be regulators. He highlights the longstanding concept of “enforcement discretion” and skewers it as one of nuclear regulation’s “greatest oxymorons.”

      Rather than demand safety compliance, the NRC historically has allowed nuclear plants to develop alternative approaches and has granted exceptions and exemptions. Recounting an episode in which he tried to abolish enforcement discretion in fire safety, Jaczko writes: “What happened over the next several weeks was more brutal than Roman imperial succession.”

      The political infighting was particularly intense after the 2011 Fukushima disaster. Jaczko visited Japan and grew impatient with the "litany of guarantees" from industry about American nuclear facilities. He tried to insist on new requirements to mitigate accidents triggered by natural disasters such as floods, earthquakes, and tsunamis. One internal NRC report drafted after Fukushima criticized the practice of relying on voluntary industry initiative to address safety concerns. Jaczko’s descriptions of other commissioners’ attempts to quash or edit the report provide a disturbing glimpse of the dynamic of trust and betrayal within the agency….

Flotilla Launches Large Survey of Antarctic Krill

[These excerpts are from an article by Erik Stokstad in the 18 January 2019 issue of Science.]

      Krill, crustaceans smaller than a cigarette, play an outsize role in the ecology of the ocean around Antarctica: Penguins, whales, and other predators feast on vast swarms of the shrimplike animals. Now, researchers have launched a broad international survey of krill’s main habitat in and around the Scotia Sea—the first in nearly 20 years—to learn whether a growing fishing industry is leaving enough for krill’s Lnatural predators….

      Soviet vessels were the first to ply the Southern Ocean for krill, which was ground into fish meal. By the 1980s, scientists began to worry about the effect on krill-feeding predators. The Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR), a treaty organization established in 1982, set tight limits on fishing, now at 620,000 tons per year. Most fishing stopped after the 1991 collapse of the Soviet Union, but it has been slowly growing again. Norway takes about half the current catch, extracting omega-3 fatty acids for nutritional supplements….

      During the survey, vessels will retrace the previous transects, measuring krill swarms with echosounders, a kind of sonar, and confirming the identification with sampling trawls. Some ships will measure oceanographic variables as well, such as temperature, currents, and plankton, to see whether they can be used to predict krill abundance….

      The survey itself won't be able to reveal how the overall krill population in the Scotia Sea might have changed since the 2000 survey, given the variability of krill populations over space and time. Finding out what drives population changes will require more research on the seasonal movement of krill, for example, and the impact of climate change. Loss of sea ice, which protects young krill from predators, is expected to reduce their abundance, and rising water temperatures and acidification could also pose serious threats—ones that even the best management plan might not avert.

Did Neurons Arise from an Early Secretory Cell?

[These excerpts are from an article by Elizabeth Pennisi in the 18 January 2019 issue of Science.]

      Swimming through the oceans, voraciously consuming plankton and other small creatures—and occasionally startling a swimmer—the beautiful gelatinous masses known as comb jellies won’t be joining Mensa anytime soon. But these fragile creatures have nerve cells—and they offer insights about the evolutionary origins of all nervous systems, including our own. Inspired by studies of a glue-secreting cell unique to these plankton predators, researchers have now proposed that neurons emerged in the last common ancestor of today’s animals—and that their progenitors were secretory cells, whose primary function was to release chemicals into the environment….

      Today, nerve cells are among the most specialized cell types in the body, able to transmit electrical signals, for example. Some versions talk to each other, others relay information from the environment to the brain, and still more send directives to muscles and other parts of the body. They are an almost universal feature of animals; only sponges and placozoans, an obscure group of tiny creatures with the simplest of animal structures, lack them….

      When and how the animal nervous sys-em arose has remained murky; however….

Why We Need Fetal Tissue Research

[These excerpts are from an editorial by Sally Temple and Lawrence S.B. Goldstein in the 18 January 2019 issue of Science.]

      A vocal minority in the United States is intent on stopping federal funding for research using human fetal tissue, citing stem cell-based or other alternatives as adequate. This view is scientifically inaccurate. It ignores the current limitations of stem cell research and disregards the value of fetal tissue research in finding therapies for incurable diseases. If there is to be continued rapid progress in treating cancer, birth defects, heart disease, and infectious diseases, then we need fetal tissue research.

      Life-saving advances, including the development of vaccines against rubella, rabies, and hepatitis A viruses, and antiviral drugs that prevent HIV/AIDS, required fetal tissue research. Today, fetal tissue is being used to develop new medicines including vaccines for HIV/AIDS, preventives for Zika virus, and immunotherapies to battle untreatable cancers.

      Although research into alternatives is worthwhile, there are several aspects of fetal tissue research for which alternatives do not and will not exist. For example, to discover which fetal cells go awry and cause childhood cancers such as retinoblastoma, a cancer of the eye, or rhabdomyosarcoma, a muscle cancer, we must understand which cells are the culprits. For that, we need access to relevant fetal tissues. Zika virus can cross the placenta and attack specific fetal brain cells. To determine the mechanism of viral entry, which cell types are vulnerable, and how to prevent infection and damage, we need access to fetal brain tissue. Beyond diseases affecting children, some forms of hereditary Alzheimer’s disease cause neural impairments in utero that persist over decades and manifest later in life. Without access to fetal cells, we cannot understand and effectively combat diseases that begin in utero.

      Fetal tissue alternatives for some applications may be developed as science advances, but this will take time. The transition to any new model of research should be data-driven and based on scientific evidence. Opponents of fetal tissue research state that human stem cell-derived organoids are adequate models, supplanting fetal tissue research, but that is incorrect….

      Although alternatives maybe established in some cases, fetal tissue remains an essential resource for many applications. It is important to remember that the fetal tissue used in research would otherwise be discarded and thus unavailable in the fight against disease. U.S. researchers also follow rigorous, well-established medical and ethical standard practices for this research. Fetal tissue research has been supported for decades by both Republican and Democratic administrations and congresses. Rigorous U.S. government-sponsored review processes have also concluded that this research is ethical and valuable.

The Bones of Bears Ears

[These excerpts are from an article by April Reese in the 18 January 2019 issue of Science.]

      Thousands of such rare fossils pepper Bears Ears, a sweep of buttes and badlands whose candy-striped sedimentary rocks catalog hundreds of millions of years of Earth’s history. The region’s rich paleontological and archaeological record—and the lobbying of southwestern tribes whose ancestors lived here—persuaded former President Barack Obama to designate the area a national monument just over 2 years ago, in the waning days of his administration.

      Now, those fossils, and the influx of special research funding that came with the designation, are under threat. In December 2017, urged on by Utah officials, President Donald Trump slashed the size of the 547,000-hectare monumpt by 85%, leaving just 82,000 hectares split into two separate units. Since Trump’s order took effect in February 2018, the excised lands, which hold thousands of Native American artifacts and sites—and possibly the world’s densest cache of fossils from the Triassic period, roughly 250 million to 200 million years ago—are open again to mining, expanded grazing, and cross-country trekking by off-mad vehicles.

      That prospect spurred the typically apolitical Society of Vertebrate Paleontology (SVP), based in Bethesda, Maryland, to sue the Trump administration in federal court, joining archaeologists, environmentalists, outdoor companies, and five Native American tribes. Their argument: The 1906 Antiquities Act used to create Bears Ears only allows presidents to establish monuments—not to drastically reduce them. The cutbacks represent an “extreme overreach of authority,” SVP said in announcing the lawsuit just days after Trump’s move. If SVP wins, the ruling could set a precedent that would help safeguard the boundaries of the 158 national monuments created under presidential authority; if it loses, future presidents could gain new powers to downsize them.

      …A similarly rich fossil trove, from the era when dinosaurs ruled, helped make the case for that monument, which was established by then-President Bill Clinton in 1996 and cut in half by Trump in another December 2017 proclamation. An influx of federal funding followed, which Polly credits with allowing researchers to uncover some of the world’s best records of the Late Cretaceous.

      Within 10 years, researchers had discovered fossils from 25 taxa new to science and documented the rise of flowering plants, insects, and the ancestors of mammals between 145 million and 66 million years ago….

      Bears Ears’s record begins earlier, more than 340 million years ago, when the supercontinent Pangaea spanned much of the planet. A tropical sea that covered the area began to fill with sediment shed by the uplifting Rocky Mountains, leaving thousands of prehistoric sea creatures, mammallike reptiles, and dinosaurs entombed in hardened mudflats. Some of those fossils help tell the story of the “great dying” 252 million years ago, which killed 96% of marine species and 70% of terrestrial ones, clearing the way for dinosaurs. Others chronicle the End Triassic extinction some 50 million years later, which wiped out 76% Of terrestrial and marine life….

      The loss of monument status means 1 those treasures could be exposed to many dangers. Off-road vehicles are now allowed to crisscross the monument’s former grounds, which are once again open to mining (although new projects must go through ELM’s usual review process). The land will also lose out on resources aimed at beefing up research, such as personnel—Grand Staircase got its own paleontologist, for example—and special funding to develop scientific and cultural resources.

      That money—part of federal funding for BLM lands protected for their scientific resources—not only funds ongoing projects and spurs new discoveries; it also helps ensure that scientists find those resources before looters do. Looting has long been a problem in San Juan County, where the monument is located….

Cheap Oil vs. Climate Change

[This excerpt is from a book report by Miriam R. Aczel in the 11 January 2019 issue of Science.]

      Since the discovery of oil in the 1930s, the six Gulf monarchies—Saudi Arabia, Qatar, Kuwait, Oman, Bahrain, and the United Arab Emirates—have become known for their seemingly endless supply of cheap energy and a growing domestic appetite for it. However, in the face of a changing climate, the very policies that led to their development and prosperity are today posing a threat as the region faces record-breaking temperatures. Jim Krane’s compelling Energy Kingdoms takes readers inside this critical energy conundrum.

      Krane evaluates the forces behind the Gulf region’s “feverish demand for its chief export commodity” and argues that the monarchies’ economic and political systems have created contradictory phenomena: Subsidization of energy; a key political institution, undermines oil and gas exporting, their main economic institution. “[L]ong term, these two crucial components of governance cannot remain in conflict. Either the political structures will bend or the economy will yield.”

How Fast Are the Oceans Warming?

[These excerpts are from an article by Lijing Cheng, John Abraham, Zeke Hausfather and Kevin E. Trenberth in the 11 January 2019 issue of Science.]

      Climate change from human activities mainly results from the energy imbalance in Earth’s climate system caused by rising concentrations of heat-trapping gases. About 93% of the energy imbalance accumulates in the ocean as increased ocean heat content (OHC). The ocean record of this imbalance is much less affected by internal variability and is thus better suited for detecting and attributing human influences than more commonly used surface temperature records. Recent observation-based estimates show rapid warming of Earth’s oceans over the past few decades….This warming has contributed to increases in rainfall intensity, rising sea levels, the destruction of coral reefs, declining ocean oxygen levels, and declines in ice sheets; glaciers; and ice caps in the polar regions. Recent estimates of observed warming resemble those seen in models, indicating that models reliably project changes in OHC….

      The fairly steady rise in OHC shows tha the planet is clearly warming. The prospects for much higher OHC, sea level, and sea-surface temperatures should be of concern given the abundant evidence of effect on storms, hurricanes, and the hydrological cycle, including extreme precipitation events. There is a clear need to continue to improve the ocean observation any analysis system to provide better estimate of OHC, because it will enable more refines regional projections of the future. In addition, the need to slow or stop the rate of climate change and prepare for the ex pected impacts is increasingly evident.

A Fresh Look at Nuclear Energy

[This excerpt is from an editorial by John Parsons, Jacopo Buongiorno, Michael Corradini and David Petti in the 11 January 2019 issue of Science.]

      We are running out of time, as the Intergovernmental. Panel on Climate Change (IPCC) warned last October in a special report, Global Warming of 1.5°C. National commitments under the 2015 Paris Agreement are only the first step toward decarbonization, but most countries are already lagging behind. It is time to take a fresh look at the role that nuclear energy can play in decarbonizing the world's energy system.

      Nuclear is already the largest source of low-carbon energy in the United States and Europe and the second-largest source worldwide (after hydropower). In the September report of the MIT Energy Initiative, The Future of Nuclear Energy in a Carbon-Constrained World, we show that extending the life of the existing fleet of nuclear reactors worldwide is the least costly approach to avoiding an increase of carbon emissions in the power sector. Yet, some countries have prioritized closing nuclear plants, and other countries have policies that undermine the financial viability of their plants. Fortunately, there are signs that this situation is changing. In the United States, Illinois, New Jersey, a and New York have taken steps to preserve their nuclear plants as part of a larger decarbonization strategy. In Taiwan, voters rejected a plan to end the use of nuclear energy. In France, decisions on nuclear plant closures must account for the impact on decarbonization commitments. In the United Kingdom, the government’s decarbonization policy entails replacing old nuclear plants with new ones. Strong actions are needed also in Belgium, Japan, South Korea, Spain, and Switzerland, where the existing nuclear fleet is seriously at risk of being phased out.

      What about the existing electricity sector in developed countries—can it become fully decarbonized? In the United States, China, and Europe, the most effective and least costly path is a combination of variable renewable energy technologies—those that fluctuate with time of day or season (such as solar or wind energy), and low-carbon dispatchable sources (whose power output to the grid can be controlled on demand). Some options, such as hydropower and geothermal energy, are geographically limited. Other options, such as battery storage, are not affordable at the scale needed to balance variable energy demand through long periods of low wind and sun or through seasonal fluctuations, although that could change in the coming decades. Nuelear energy is one low-carbon dispatchable option that is virtually unlimited and available now. Excluding nuclear power could double or triple the average cost of electricity for deep decarbonization scenarios because of the enormous overcapacity of solar energy, wind energy, and batteries that would be required to meet demand in the absence of a dispatchable low-carbon energy source.

      One obstacle is that the cost of new nuclear plants has escalated, especially in the first-of-a-kind units currently being deployed in the United States and Western Europe. This may limit the role of nuclear power in a low-carbon portfolio and raise the cost of deep decarbonization. The good news is that the cost of new nuclear plants can be reduced, not only in the direct cost of the equipment, but also in the associated civil structures and in the processes of engineering, licensing, and assembling the plant….

Seeing the Dawn

[These excerpts are from an article by Robert F. Service in the 11 January 2019 issue of Science.]

      A cataclysm may have jump-started life on Earth. A new scenario suggests that some 4.47 billion years ago—a mere 60 million years after Earth took shape and 40 million years after the moon formed—a moon-size object sideswiped Earth and exploded into an orbiting cloud of molten iron and other debris.

      The metallic hailstorm that ensued likely lasted years, if not centuries, ripping oxygen atoms from water molecules and leaving hydrogen behind. The oxygens were then free to link with iron, creating vast rust-colored deposits of iron oxide across our planet’s surface. The hydrogen formed a dense atmosphere that likely lasted 200 million years as it ever so slowly dissipated into space.

      After things cooled down, simple organic molecules began to form under the blanket of hydrogen. Those molecules, some scientists think, eventually linked up to form RNA, a molecular player long credited as essential for life’s dawn. In short, the stage for life's emergence was set almost as soon as our planet was born.

      …No rocks or other direct evidence remain from the supposed cataclysm….

      The metal-laden rain accounts for the distribution of metals across our planet’s surface today. The hydrogen atmosphere would have favored the emergence of the simple organic molecules that later formed more complex molecules such as RNA. And the planetary crash pushes back the likely birthdate for RNA, and possibly life’s emergence, by hundreds of millions of years, which better aligns with recent geological evidence suggesting an early emergence of life.

      The impact scenario joins new findings from laboratory experiments suggesting how the chemicals spawned on early Earth might have taken key steps along the road to life—steps that had long baffled researchers. Many in the field see a consistent narrative describing how and when life was born starting to take shape….

      The case isn’t settled, Luptak and others say. Researchers still disagree, for example, over which chemical path most likely gave rise to RNA and how that RNA combined with proteins and fats to form the earliest cells….

      Since the 1960s, a leading school of thought has held that RNA arose first, with DNA and proteins evolving later. That’s because RNA can both serve as a genetic code and catalyze chemical reactions. In modern cells, RNA strands still work alongside proteins at the heart of many crucial cellular machines.

      In recent years, chemists have sketched out reactions that could have produced essential building blocks for RNA and other compounds….

The Last Resort

[These excerpts are from an article by Richard Conniff in the January 2019 issue of Scientific American.]

      …In a special report in October 2018, the Intergovernmental Panel on Climate Change warned that we have just 12 years to act if we hope to avoid slipping past 1.5 degrees C, the level regarded by most scientists as the furthest we can go if we hope to preserve life more or less as we know it.

      Staying under that threshold mandates a specific “carbon budget,” an overall amount of carbon dioxide we can add to the atmosphere without pushing warming beyond that temperature. At today’s emissions—about 40 billion to 50 billion tons a year—“there may be only five years’ worth of CO2 emissions left” in the 1.5-degree scenario….

      On a hardened lava field of boulders and moss in the foothills just outside Reykjavlk, Iceland, a machine the size of a one-car garage pulls air through a chemical filter that extracts carbon dioxide. It is powered by waste heat from the geothermal power plant next door, and it pumps the captured carbon dioxide more than 700 meters underground, where the gas reacts with basalt rock and becomes solid mineral. Climeworks, a Swiss start-up, calls the operation the first direct air capture and storage plant in the world. It sequesters a modest 50 tons of carbon dioxide a year.

      Direct air capture and storage may be the most straightforward path to negative emissions: banks of fans would harvest CO2 from the sky and bury it. Scientific scenarios project that this technology could remove 10 billion to 15 billion tons of carbon dioxide a year by the end of the century; a few experts think 35 billion or 40 billion tons may be possible. This is such a tantalizing prospect that many climate scientists worry it could pose a moral hazard: people might think they can delay fossil-fuel reductions now in the hope of technological salvation later….

      Direct air capture also consumes enormous amounts of energy. Removing a million tons of carbon dioxide a year would require a 300- to 500-megawatt power plant….If that were a coal-fired plant, it would create more emis-sions than it would remove. If power came from solar or wind farms, it would cover a lot of land that might already be in demand for farming or nature. And of course, a million tons would barely make a dent in the target of 20 billion tons a year….

On the Safe Side

[These excerpts are from an article by Eric Lindberg in the Winter 2018 issue of the USC Trojan Family.]

      Childhood is a time for wonder and learning, I for exploration and discovery, for making new friends and building confidence. But sometimes that period of innocence is shattered by violence, discrimination or harassment. And that turmoil tends to occur where kids spend most of their day: at school.

      Teachers and administrators deal with bad behavior every day in classrooms across the country.

      Nearly eight in 10 public K-12 schools reported at least one incident of violence, theft or other crime on campus in 2016, according to the National Center for Education Statistics. The latest statewide data show one third of students in California schools are bullied. Rates of suicide and depression among teens have increased substantially in recent decades. And school shootings, although still extremely rare, continue to garner widespread attention.

      So how can we make our schools safer and ensure that students can thrive…?

      There is some cause for optimism, he says, noting that overall crime and violence have decreased both in U.S. society in general and in schools since the mid-1990s, for reasons that remain unclear. Researchers have found that shooting incidents involving students are on the decline, as are virtually all indicators of violence and crime in schools. Nevertheless, many remain fearful.

      A recent survey found that 57 percent of teens say they are worried about a shooting happening at their school. Parents of teens are even more likely to be concerned; 63 percent report being at least somewhat worried about school shootings. Many researchers trace this perception of exaggerated danger in schools to breathless media coverage of high-profile incidents. Mass shootings like the recent tragedy in Parkland, Florida, can have a dramatic effect on feelings of safety….

Toxic Baby Food? Really?

[These excerpts are from an editorial by the editors in the January 2019 issue of Scientific American.]

      Many babies’ first solid food is rice cereal. It is a childhood staple, commonly recommended by pediatricians. And it is often poisoned—at least a little bit. Studies have found that many brands contain measurable amounts of inorganic arsenic, the most toxic kind. It’s not just rice: an August 2018 study by Consumer Reports tested 50 foods made for babies and toddlers, including organic and nonorganic brands such as Gerber, Earth’s Best, Beech-Nut and other popular labels, and found evidence of at least one dangerous heavy metal in every product. Fifteen of the 50 contained enough contaminants to pose potential health risks to a child eating one serving or less a day.

      Heavy metals can impair cognitive development in children, who are especially at risk because of their smaller size and tendency to absorb more of these substances than adults do. Inorganic arsenic in drinking water has been found to lower the IQ scores of children by five to six points. And asheavy metals accumulate in the body over time, they can raise the risk of cancer, reproductive problems, type 2 diabetes, cardiovascular disease and cognitive issues. Of course, finding out your favorite brand is contaminated is not a reason to panic. Low levels of exposure for short periods are unlikely to cause devastating effects, and parents should focus on reducing the overall levels of these toxic substances in their children's total diet to limit harm.

      Heavy metals occur naturally on Earth and are present in soil and water. But pesticides, mining and pollution boost their concentrations, and farming and food manufacturing processes can contribute even more. Some crops inevitably absorb more heavy metals. Rice, for example, readily takes in arsenic both because of its particular physiology and because it is often grown in fields flooded with water, which is a primary source of the metal.

      Cereal makers are clearly capable of keeping baby food poison-free: roughly a third of the products Consumer Reports tested did not contain worrisome metal levels. Companies just do not take enough safety steps….

      Some companies are already trying to investigate the sources of contamination in their products and reduce them. More should follow and be transparent about these efforts. But the best chance of real change from food companies most likely will come with regulation.

      Currently there are no U.S. rules on acceptable levels of heavy metals in baby foods. In 2012, 2015 and 2017 Congress tried and failed to pass legislation imposing limits on arsenic and lead in fruit juice and rice products….

Fast and Furious

[These excerpts are from an article in the Winter 2019 issue of the American Museum of Natural History Rotunda.]

      There’s still a lot we don’t know about the Cretaceous Period’s most famous predator, Tyrannosaurus rex. One thing is for sure: T. rex was a giant. Its size is one of the extinct dinosaur’s most impressive features—along with its bone-crushing bite and disproportionally tiny arms, of course.

      Getting a fuller understanding of T. rex the giant requires scientists to try to learn more about T. rex as a tyke—before it was a mega-predator and, when it was still something else’s prey—as well as its lesser-known, lesser-sized relatives….

      Like many living species, T. rex hatchlings started out a fraction of the size of an adult dinosaur—which could weigh upward of 15,000 pounds, or about the same as five compact cars. But what the small theropods lacked in size, they made up for in speed: scientists think that T. rex gained up to 4.6 pounds a day, or an astonishing 1,690 pounds per year, until its early 20s.

      A ferociously rapid growth rate was one of the things that set T. rex apart from its Mesozoic peers. It matured at an exceptionally quick clip for a dinosaur, leaping way ahead in size of other tyrannosaur species like Albertosaurus and Gorgosourus around age 12. That gave this predator a distinct advantage: by growing out of its young and vulnerable phase quickly, T. rex could spend about 30 percent of its lifetime as one of the largest predators ever to walk the Earth. Compare that to modern crocodilians—close cousins that grow very slowly and, while reaching relatively massive sizes, attain only a fraction of the size and weight of an adult T. rex.

      Paleontologists have derived T. rex’s stunning growth rate by examining a cross-section of fossilized bones for growth lines—markings that are similar to tree rings, and present in nearly all vertebrates. For dinosaurs like T. rex, researchers often sample the thigh bone (femur)….also found success sampling the pelvis, calf bone (fibula), ribs, gastralia, and skull bones. And as with trees, bone growth rings offer a glimpse into an organism’s life history: in T. rex, wide gaps between lines record growth spurts at early ages, and lines that form closer together show a slowdown in growth as the animal approached adulthood….

      Growth rates also allow scientists to peek back at an animal’s early years. Scientists have yet to find a T. rex hatchling fossil. But recent studies based on the growth curve of T. rex suggest that these animals would have been around 2 feet long straight out of the egg, and as juveniles may have weighed as little as 10 pounds….

      Along with growth curves, paleontologists have also looked to other tyrannosaurs—a group that’s bigger, and better studied, today than ever before— for additional clues about how T. rex may have developed and behaved….

      Life expectancy for T. rex improved significantly as it grew, but juvenile fossil specimens are very rare. When a specimen is discovered, paleontologists run up against another problem: how to confirm that a fossil is of a young animal, not of an adult of a smaller, totally new species?

Tropical Uplift May Set Earth’s Thermostat

[These excerpts are from an article by Paul Voosen in the 4 January 2019 issue of Science.]

      Hate the cold? Blame Indonesia. It may sound odd, given the contributions to global warming from the country’s 270 million people, rampant deforestation, and frequent carbon dioxide (CO2)-belching volcanic eruptions. But over much longer times, Indonesia is sucking CO2 out of the atmosphere.

      Many mountains in Indonesia and neighboring Papua New Guinea consist of ancient volcanic rocks from the ocean floor that were caught in a colossal tectonic collision between a chain of island volcanoes and a continent, and thrust high. Lashed by tropical rains, these rocks hungrily react with CO2 and sequester it in minerals. That is why, with only 2% of the world’s land area, Indonesia accounts for 10% of its long-term CO2 absorption. Its mountains could explain why ice sheets have persisted, waxing and waning, for several million years (although they are now threatened by global warming).

      Now, researchers have extended that theory, finding that such tropical mountain-building collisions coincide with nearly all of the half-dozen or so significant glacial periods in the past 500 million years….

      Most geologists agree that long-term changes in the planet’s temperature are governed by shifts in CO2, and that plate tectonics somehow drives those shifts as it remakes the planet's surface. But for several decades, researchers have debated exactly what turns the CO2 knob. Many have focused on the volcanoes that rise where plates dive beneath one another. By spewing carbon from Earth’s interior, they could turn up the thermostat. Others have emphasized rock weathering, which depends on mountain building driven by plate tectonics. When the mountains contain seafloor rocks rich in calcium and magnesium, they react with CO2 dissolved in rainwater to form limestone, which is eventually buried on the ocean floor. Both processes matter….

      Having the right rocks to drive the CO2-chewing reaction is not sufficient. Climate matters, too. For example, the Siberian Traps, a region that saw devastating volcanic eruptions 252 million years ago, are rich in such rocks but absorb little….

Do Plants Favor Their Kin?

[These excerpts are from an article by Elizabeth Pennisi in the 4 January 2019 issue of Science.]

      For people, and many other animals, family matters. Consider how many jobs go to relatives. Or how an ant will ruthlessly attack intruder ants but rescue injured, closely related nestmates. There are good evolutionary reasons to aid relatives, after all. Now; it seems, family feelings may stir in plants as well.

      A Canadian biologist planted the seed of the idea more than a decade ago, but many plant biologists regarded it as heretical—plants lack the nervous systems that enable animals to recognize kin, so how can they know their relatives? But with a series of recent findings, the notion that plants really do care for their most genetically close peers—in a quiet, plant-y way—is taking root. Some species constrain how far their roots spread, others change how many flowers they produce, and a few tilt or shift their leaves to minimize shading of neighboring plants, favoring related individuals….

      Beyond broadening views of plant behavior, the new work may have a practical side. In September 2018, a team in China reported that rice planted with kin grows better, a finding that suggested family ties can be exploited to improve crop yields….

      …She grew American searocket (Calcile edentula), a succulent found on North American beaches, in pots with relatives or with unrelated plants from the same population. With strangers, the searocket greatly expanded its underground root system, but with relatives, it held these competitive urges in check, presumably leaving more room for kin roots get nutrients and water. The claim, published in 2007, shocked colleagues. A few sharply criticized the work, citing flawed st-tistics and bad study design.

      Since then, however, other researchers have confirmed her findings….After growing 770 seedlings in pots either alone or with three or six neighbors of varying relatedness, the team found the plants grown with kin put out more flowers, making them more alluring to pollinators. The floral displays were especially big in plants in the most crowded pots of relatives….

      Doubts linger. Is a plant identifying genetic kin, or simply recognizing that its neighbor is more or less similar to itself…?

      Sagebrush bushes (Artemisia tridentate) have provided some strong clues, however. When injured by herbivores, these plants release volatile chemicals that stimulate neighboring sagebrush to make chemicals toxic to their shared enemies….

      Since then, he has shown that when sunflower kin are planted close together, they, too, arrange themselves to stay out of one another's way. The sunflowers incline their shoots alternately toward one side of the row or the other….Taking advantage of the effect, they planted 10 to 14 related plants per square meter—an unheard of density for commercial growers—and got up to 47% more oil from plants that were allowed to lean away from each other than plants forced to grow straight up.

Small Steps, Big Changes

[These excerpts are from an article by Joshua P. Starr in the December 2018/January 2019 issue of Phi Delta Kappan.]

      If we want to make significant improvements in public education, then our goal shouldn't be to find a few more superstars. We know that in every profession people tend to be distributed along a bell curve, with the largest group performing somewhere in the middle. That certainly applies to the 3.7 million teachers working in our public schools. So the way to make the biggest difference is to help the largest group of teachers, those in the middle of the pack, to make regular, ongoing progress, so that the whole bell curve shifts. If we were to bump up the average level of teaching performance across the country over a number of years, that would translate to historic gains in student learning.

      But if our goal is to promote steady progress on a large scale, what does that mean for educational leadership? How do we organize and lead school systems to help our average-performing teachers and staff to get better at their work? I believe, and decades of research findings suggest, that it starts with defining a clear vision for what students need to know and be able to do, and every part of the school system must then be aligned with that goal.

      Again, I know this isn’t the most exciting sales pitch, but it’s much more effective for school and district leaders to implement a number of deliberate and modest, well-aligned changes thoughtfully than to throw themselves (and their professional ambitions) into one or two big, splashy, high-profile initiatives. Creating this sort of systemwide alignment requires us to take a careful look at every part of the system — policy, curriculum, teacher development, assessment, accountability, resource allocation, staffing, community engagement, and school culture — and try to find realistic ways for each to make a stronger contribution to our shared goals. Everything matters, and small steps add up….

      …Whether they focus on curriculum, grading, student assignment, equity, or another topic, policy discussions give teachers and administrators the opportunity to clarify what they want their students to learn and what kinds of support those students will require….

      …Teachers often and rightly complain that one-size-fits-all district-mandated training is meaningless. Yet, educators shouldn’t be left to their own devices either, as professional learning must be aligned with the priorities of the school and system, as well as the developmental needs of both teacher and students.

The Happy (and not so Happy) Accidents of Bush-Obama School Reform

[These excerpts are from an article by Frederick M. Hess and Michael Q. McShane in the December 2018/January 2019 issue of Phi Delta Kappan.]

      The American educational system is sprawling, diverse, and complex. It sits within a political system that itself is sprawling, diverse, and complex. In turn, that system sits within an American culture that is also sprawling, diverse, and complex. These are not design flaws. They represent —for good and bad — the true face of American democracy after more than two centuries of evolution.

      But if our educational system resembles a riddle wrapped in an enigma inside of a mystery, then it must be extraordinarily difficult to predict how reforms will unspool. Thus, reformers should be open to serendipity and Lvalue its gifts….

      No matter how pure our motives or brilliant our theory of action, we do well to recognize that school reforms rarely work as intended, and they sometimes only serve to make matters worse. That’s especially true then it comes to policy implementation. More often than not, students, teachers, and administrators react and behave in unexpected ways, or political forces and real-world dynamics interfere with our carefully designed plans.

      In the case of test-based teacher evaluation and the Common Core, advocates dug in their heels and kept insisting that their ambitious plans made sense — even as those reforms began to face practical challenges and backlash. Further, because policy makers attached timelines to these initiatives, state leaders felt compelled to charge forward, whatever the obstacles, and they were loath to make course corrections for fear of missing benchmarks or breaking promises.

      Thus, instead of taking parents and educators’ concerns seriously and admitting things weren’t playing out as they’d hoped, proponents tended to dismiss their critics as ideological, unreasoning, and “anti-child,” which only made it tougher to find common ground or defuse concerns. Over time, they became more and more preoccupied with tweaking their messages and securing short-term political wins, rather than addressing significant problems or trying to understand the growing opposition to their policies.

      When advocates build a head of steam behind a particular school reform, they may be reluctant to slow down, acknowledge concerns, and address obvious problems. But if they can bring themselves to hit the brakes when necessary; rather than trying to plow through every obstacle, Lthen they’ll be much better equipped for the long haul….

      For all the uncertainties of education policy, some truisms do hold, no matter how inconvenient we may find them: Incentivizing certain behaviors will tend to cause more of that behavior; people will go to great lengths to keep their jobs; if people distrust those who make the rules, they will push back on those rules; and if reformers neglect to anticipate and account for these things, they will likely encounter more unhappy accidents than happy ones.

How Cognitive Psychology Informs Classroom Practice

[These excerpts are from an article by Pooja K. Agarwal and Henry L. Roediger III in the December 2018/January 2019 issue of Phi Delta Kappan.]

      1. Retrieval practice boosts learning by pulling information out of students’ heads (by responding to a brief writing prompt, for example), rather than cramming information into their heads (by lecturing at students, for example). In the classroom, retrieval practice can take many forms, including a quick no-stakes quiz. When students are asked to retrieve new information, they don't just show what they know, they solidify and expand it.

      2. Feedback boosts learning by revealing to students what they know and what they don’t know. At the same time, this increases students' metacognition — their understanding about their own learning progress.

      3. Spaced practice boosts learning by spreading lessons and retrieval opportunities out over time so that new knowledge and skills are not crammed in all at once. By returning to content every so often, students’ knowledge has time to be consolidated and then refreshed.

      4. Interleaving — or practicing a mix of skills (such as doing addition, subtraction, multiplication, and division problems all in one sitting) — boosts learning by encouraging connections between and discrimination among closely related topics. Interleaving sometimes slows students’ initial learning of a concept, but it leads to greater retention and learning over time….

      Many teachers already implement these strategies in one form or another. But they may be able to get much more powerful results with a few small tweaks. For example, we often observe teachers using think-pair-share activities in their classrooms — typically, they will give students a few minutes on their own to think about a topic or prompt, then a few more minutes to discuss it with a partner, and then a chance to share their ideas as part of a larger class discussion. But what, exactly, are students doing during the think stage? They could easily be daydreaming, or wondering what to eat for lunch, rather than actively considering the prompt. But if the teacher simply asks them to write down a quick response, rather than just think, it becomes an opportunity for retrieval practice, ensuring that students are drawing an idea out of their heads and onto the paper.

      Similarly, rather than assigning students to consider a new topic, the teacher might ask them to do a think-pair-share about content they learned the day or week before — and now it becomes an opportunity for spaced practice; students get to return to material and solidify their under-standing of it.

      Here’s another example: We often observe teachers begin their classes by saying something to the effect of, “Here’s what we did yesterday ...” and then reviewing the content. Instead, they can pose it as a question, “What did we do yesterday?” and give students a minute to write down what they remember. It's a subtle shift (from a lecture by the teacher to an opportunity for retrieval practice), but it can significantly improve student learning, without requiring additional preparation or classroom time. Even a single question, writing prompt, or quick no-stakes quiz can make a difference, encouraging students to pull information out of their heads rather than cramming it into them via lecturing or telling.

      Why do these strategies improve learning? Consider this quick question: Who was the fourth president of the United States? A plausible answer may have jumped instantly to mind, but you probably had to struggle mentally to come up with a response. It’s precisely this productive struggle or “desirable difficulty” during retrieval practice and the three additional strategies that improves learning. (By the way, the fourth president was James Madison, but you’ll likely remember that much better if you managed to retrieve it from your memory rather than waiting for us to remind you of the name!)

      Teachers can use these four strategies (retrieval practice, feedback-driven metacognition, spaced practice, and interleaving) with confidence because they are strongly backed by research both in laboratories and classrooms. The rigor of science gives us confidence that these strategies aren’t fads, and successful classroom implementation gives us confidence that they work in the real world, not just in the laboratory.

Spin Control

[These excerpts are from an article by Jennifer Chu in the January-February 2019 issue of MIT News.]

      The Beaufort Gyre is an enormous, 600-mile-wide pool of swirling cold, fresh water in the Arctic Ocean, just north of Alaska and Canada. In the winter, this current is covered by a thick cap of ice. Each summer, as the ice melts away, the exposed gyre gathers up sea ice and river runoff, and draws it down to create a huge reservoir of frigid fresh water equal to the volume of all the Great Lakes combined.

      Scientists at MIT have now identified a key mechanism, which they call the “ice-ocean governor,” that controls how fast the Beaufort Gyre spins and how much fresh water it stores. In a recent paper in Geophysical Research Letters, the researchers report that the Arctic's ice cover essentially sets a speed limit on the gyre’s spin.

      In the past two decades, as surface air temperatures have risen, the Arctic’s summer ice has progressively shrunk. The team has observed that with less ice available to control the Beaufort Gyre’s spin, the current has sped up in recent years, gathering up more sea ice and expanding in both volume and depth

      If Arctic temperatures continue to climb, the researchers predict, the mechanism governing the gyre's spin will diminish. With no governor to limit its speed, the gyre is likely to transition into “a new regime” and eventually spill over like an overflowing bathtub, releasing huge volumes of cold, fresh water into the North Atlantic. That could affect the global climate and ocean circulation….

      As Arctic temperatures have risen inl the last two decades, summertime ice has shrunk with each year, the speed of the Beaufort Gyre has increased, and its currents have become more variable and unpredictable, and they are only slightly slowed by the return of ice in the winter.

      An increasingly unstable Beaufort Gyre could also disrupt the Arctic's halocline—the underlying layer of ocean water that insulates ice at the surface from much deeper, warmer, and saltier water. If the halocline is weakened by a more unstable gyre, this could encourage warmer waters to rise up, further melting the Arctic ice….

The Science of Slime

[These excerpts are from an article by Katharina Ribbeck in the January-February 2019 issue of MIT News.]

      Snot. Boogers. Phlegm. The goo that drips from your nose when you have a cold. No matter what you call it, mucus has a bad reputation as an unpleasant waste product, a sign of disease.

      But despite its high ick factor, the slimny substance performs a remarkable range of vital functions. After all, it lines more than 200 square meters of our bodies—from our mouths to the digestive system, urinary tract, lungs, eyes, and cervix. It lubricates and hydrates, lets us swallow, determines what we taste and smell, and selectively filters nutrients, toxins, and living cells such as bacteria, sperm cells, and fungi….

      …mucus is very successful at “taming” normally pathogenic microbes. Until recently, scientists thought this was because it acted as a mechanical barrier, trapping bacteria and other pathogens….

      The primary building blocks of mucus are mucins—long, bottlebrush-like proteins with many sugar molecules called glycans attached. And mucins…actually disrupt many key functions of infectious bacteria….

      With those powers cut off, bacteria can no longer colonize on a surface to form persistent slimy layers called biofilms, which tend to be more harmful than the cells are individually: they can cause a wide range of health problems, including dental cavities and ulcers, and can prove fatal for people with cystic fibrosis….

      More than 10% of babies born worldwide arrive before full term, defined as 37 weeks of gestation, but there had been no reliable way to predict preterm labor….the mucus from women at high risk of early labor is mechanically weaker, more elastic, more permeable, and less adhesive. Preterm birth may occur because the cervical mucus is more susceptible to invasion by microbes that can cause infection.

      Other conditions that alter mucus include digestive diseases such as Crohn’s and ulcerative colitis, as well as respiratory diseases….

Artificial Intelligence and Ethics

[This excerpt is from an article by Jonathan Shaw in the January-February 2019 issue of Harvard Magazine.]

      “Artificial intelligence” refers to systems that can be designed to take cues from their environment and, based on those inputs, proceed to solve problems, assess risks, make predictions, and take actions. In the era predating powerful computers and big data, such systems were programmed by humans and followed rules of human invention, but advances in technology have led to the development of new approaches. One of these is machine learning, now the most active area of AI, in which statistical methods allow a system to “learn” from data, and make decisions, without being explicitly programmed. Such systems pair an algorithm, or series of steps for solving a problem, with a knowledge base or stream—the information that the algorithm uses to construct a model of the world.

      Ethical concerns about these advances focus at one extreme on the use of AI in deadly military drones, or on the risk that Al could take down global financial systems. Closer to home, Al has spurred anxiety about unemployment, as autonomous systems threaten to replace millions of truck drivers, and make Lyft and Uber obsolete. And beyond these larger social and economic considerations, data scientists have real concerns about bias, about ethical implementations of the technology, and about the nature of interactions be-tween AI systems and humans if these systems are to be deployed properly and fairly in even-the most mundane applications.

      Consider a prosaic-seeming social change: machines are already being given the power to make life-altering, everyday decisions about people. Artificial intelligence can aggregate and assess vast quantities of data that are sometimes beyond human capacity to analyze unaided, thereby enabling AI to make hiring recommendations, determine in seconds the creditworthiness of loan applicants, and predict the chances that criminals will re-offend.

      But such applications raise troubling ethical issues because AI systems can reinforce what they have learned from real-world data, even amplifying familiar risks, such as racial or gender bias. Systems can also make errors of judgment when confronted with unfamiliar scenarios. And because many such systems are “black boxes,” the reasons for their decisions are not easily accessed or understood by humans—and therefore difficult to question, or probe.

      Examples abound. In 2014, Amazon developed a recruiting tool for identifying software engineers it might want to hire; the system swiftly began discriminating against women, and the company abandoned it in 2017. In 2016, ProPublica analyzed a commercially developed system that predicts the likelihood that criminals will re-offend, created to help judges make better sentencing decisions, and found that it was biased against blacks. During the past two years, self-driving cars that rely on rules and training data to operate have caused fatal accidents when confronted with unfamiliar sensory feedback or inputs their guidance systems couldn’t interpret. The fact that private commercial developers generally refuse to make their code available for scrutiny, because the software is considered proprietary intellectual property, is another form of non-transparency—legal, rather than technical.

      Meanwhile, nothing about advances in the technology, per se, will solve the underlying, fundamental problem at the heart of AI, which is that even a thoughtfully designed algorithm must make decisions based on inputs from a flawed, imperfect, unpredictable, idiosyncratic real world.

Needle in the Haystack

[These excerpts are from an article by Thomas Hingham and Katrina Douka in the December 2018 issue of Scientific American.]

      Denisova Cave is at the center of a revolution in scientists’ understanding of how our ancestors in the Paleolithic, or Old Stone Age, behaved and interacted. Our species, Homo sapiens, originated in Africa hundreds of thousands of years ago. When it eventually began spreading into Europe and Asia, it encountered other human species, such as the Neandertals, and shared the planet with them for millennia before those archaic species disappeared. Scientists know these groups encountered one another because people today carry DNA from our extinct relatives—the result of interbreeding between early H. sapiens and members of those other groups. What we do not yet know and are eager to ascertain is when and where they crossed paths, how often they interbred and how they might have influenced one another culturally. We actually have quite a few important archaeological sites from this transitional period that contain stone tools and other artifacts. But many of these sites, including Denisova, lack human fossils that are complete enough to attribute to a particular species on the basis of their physical traits. That absence has hindered our ability to establish which species made what—and when.

      Now a technique for identifying ancient bone fragments, known as zooarchaeology by mass spectrometry (ZooMS), is finally allowing researchers to start answering these long-standing questions. By analyzing collagen protein preserved in these seemingly uninformative fossil scraps, we can identify the ones that come from the human/great ape family and then attempt to recover DNA from those specimens. Doing so can reveal the species they belong to—be it Neandertal, H. sapiens or something else. What is more, we can carry out tests to determine the ages of the fragments.

      Directly dating fossils is a destructive process—one has to sacrifice some of the bone for analysis. Museum curators are thus usually loath to subject more complete bones to these tests. But they have no such reservations with the scraps.

      The ability to directly date fossils found in association with artifacts is especially exciting with regard to Denisova and other sites we know sheltered multiple human species in the past. A number of researchers have argued that symbolic and decorative artifacts, which are proxies for modern cognitive abilities, are unique to H. sapiens. Others maintain that Neandertals and other species made such items, too, and may have even passed some of their traditions along to the H. sapiens they met. The ability to identify and date these fossil fragments means researchers can begin to reconstruct the chronology of these sites in far greater detail and elucidate a critical chapter of human prehistory….

      ZooMS, also called collagen peptide mass fingerprinting, allows investigators to assign fragments of bone to the proper taxonomic group by analyzing the proteins in bones. Bone collagen protein is made up of hundreds of small compounds called peptides that vary slightly among different types of animals. By comparing the peptide signatures of mystery bones against a library of such signatures from known animals, it is possible to assign the unidentified bones to the correct family, genus and sometimes species….

Meat Grown from Stem Cells

[These excerpts are from an article by G. Owen Schaefer in the December 2018 issue of Scientific American.]

      Imagine biting into a juicy beef burger that was produced without killing animals. Meat grown in a labora-tory from cultured cells is turning that vision into a reality. Several start-ups are developing lab-grown beef, pork, poultry and seafood….

      If widely adopted, lab-grown meat, also called clean meat, could eliminate much of the cruel, unethical treatment of animals that are raised for food. It could also reduce the considerable environmental costs of meat production; resources would be needed only to generate and sustain cultured cells, not an entire organism from birth.

      The meat is made by first taking a muscle sample from an animal. Technicians collect stem cells from the tissue, multiply them dramatically and allow them to differentiate into primitive fibers that then bulk up to form muscle tissue. Mesa Meat says that one tissue sample from a cow can yield enough muscle tissue to make 80,000 quarter-pounders.

      A number of the start-ups say they expect to have products for sale within the next fewyears. But clean meat will have to overcome a number of barriers if it is to be commer-cially viable.

      Two are cost and taste. In 2013, when a burger made from lab-grown meat was presented to journalists, the patty cost more than $300,000 to produce and was overly dry (from too little fat). Expenses have since fallen. Memphis Meats reported this year that a quarter-pound of its ground beef costs about $600. Given this trend, clean meat could become competitive with traditional meat within several years. Careful attention to texture and judicious supplementing with other ingredients could address taste concerns.

      To receive market approval, clean meat will have to be proved safe to eat. Although there is no reason to think that lab-produced meat would pose a health hazard, the FDA is only now beginning to consider how it should be regulated. Meanwhile traditional meat producers are pushing back, arguing that the lab-generated products are not meat at all and should not be labeled as such, and surveys show that the public has only tepid interest in eating meat from labs. Despite these challenges, the clean meat companies are forging ahead. If they can succeed in creating authentic-tasting products that are also affordable, clean meat could make our daily eating habits more ethical and environmentally sustainable.

Mimicking Spider Silk

[This excerpt is from an article by Prachi Patel in the December 2018 issue of Scientific American.]

      Spiders spin the stuff of engineers’ dreams. Their silk is as strong as steel, stretchy, nontoxic and biodegradable. But spiders are not easy to farm. Each produces only a minuscule amount of silk, and some are cannibalistic. For decades scientists have tried to mimic the silvery strands to use for sutures, athletic gear and bulletproof vests, but their synthetic fibers have fallen short. Now a team has coaxed bacteria to produce silk as tough and elastic as the natural version.

      Researchers have previously transplanted silk-making DNA from spiders into bacteria, silkworms, plants and even goats in an effort to mass-produce the substance. Until now, however, the best engineered fibers have been only half as strong as the real thing. The secret to spider silk’s strength lies in large protein molecules composed of hundreds of strings of repeated amino acids encoded by similarly lengthy, repetitive DNA sequences….

Fossils Push Back Origin of Key Plant Groups Millions of Years

[These excerpts are from an article by Elizabeth Pennisi in the 21 December 2018 issue of Science.]

      Paleobotanists exploring a site near the Dead Sea have unearthed a startling connection between today’s conifer forests in the Southern Hemisphere and an unimaginably distant time torn apart by a global cataclysm. Exquisitely preserved plant fossils show the podocarps, a group of ancient evergreens that includes the massive yellowwood of South Africa and the red pine of New Zealand, thrived in the Permian period, more than 250 million years ago. That's tens of millions of years earlier than thought, and it shows that early podocarps survived the “great dying” at the end of the Permian, the worst mass extinction the planet has ever known.

      …the fossils push back the origins not just of podocarps, but also of groups of seed ferns and cycadlike plants. Beyond altering notions of plant evolution, the discoveries lend support to a 45-year-old idea that the tropics serve as a “cradle” of evolution….

      During the Permian, from 299 million to 251 million years ago, Earth's landmasses had merged to form a supercontinent, bringing a cooler, drier climate. Synapsids, thought to be ancient predecessors of mammals, and saumpsids, ancestors to reptiles and birds, roamed the landscape. Simple seed-bearing plants had already appeared on the scene. Family trees reconstructed from the genomes of living plants suggest more sophisticated plant groups might also have evolved during the Permian, but finding well-preserved plant fossils from that time has been difficult.

      …Many of the fossils preserve the ancient plants' cuticle, a waxy surface layer that captures fine features, such as the leaf pores called stomata. That made it possible for the team to positively identify many of the plants….

      Such finds could help resolve an ongoing debate about why the tropics have more species than colder latitudes do. Some have suggested that species originate at many latitudes but are more likely to diversify in the tropics, with its longer growing seasons, higher rainfall and temperatures, and other features. But another theory proposes that most plant—and animal—species actually got their start near the equator, making the low latitudes an evolutionary “cradle” from which some species migrate north and south….

      It’s not clear how the newfound Permian plants made it through the great dying, a 100,000-year period when, for reasons that are still unclear, 90% of marine life and 70% of life on land disappeared. But their presence in the Permian raises the possibility that other plant groups thought to have later origins actually emerged then in the tropics….

Antarctic Ice Melt 125,000 Years Ago Offers Warning

[These excerpts are from an article by Paul Voosen in the 21 December 2018 issue of Science.]

      Some 125,000 years ago, during the last brief warm period between ice ages, Earth was awash. Temperatures during this time, called the Eemian, were barely higher than in today’s greenhouse-warmed world. Yet proxy records show sea levels were 6 to 9 meters higher than they are today, drowning huge swaths of what is now dry land.

      Scientists have now identified the source of all that water: a collapse of the West Antarctic Ice Sheet. Glaciologists worry about the present-day stability of this formidable ice mass. Its base lies below sea level, at risk of being undermined by warming ocean waters, and glaciers fringing it are retreating fast. The discovery, teased out of a sediment core and reported last week at a meeting of the American Geophysical Union in Washington, D.C., validates those concerns, providing evidence that the ice sheet disappeared in the recent geological past under climate conditions similar to today’s….

      …Once the ancient ice sheet collapse got going, some records suggest, ocean waters rose as fast as some 2.5 meters per century.

      …Global temperatures were some 2°C above preindustrial levels (compared with 1°C today). But the cause of the warming was not greenhouse gases, but slight changes in Earth's orbit and spin axis, and Antarctica was probably cooler than today. What drove the sea level rise, recorded by fossil corals now marooned well above high tide, has been a mystery.

Choices in the Climate Commons

[These excerpts are from an editorial by Scott Barrett in the 14 December 2018 issue of Science.]

      Climate change is a tragedy of the commons of existential importance….American ecologist Garrett Hardin’s classic article, “The Tragedy of the Commons,” published in Science 50 years ago this week, vividly describes the dilemma that causes this behavior….

      …Hardin’s proposed corrective is “mutual coercion.” Writing in 1651, British philosopher Thomas Hobbes similarly concluded that a sovereign is needed to tie people “by fear of punishment to the performance of their covenants.”

      However, a critical difference between climate change and Hardin’s parable is that the players in the climate game are nation states. Although individuals can be subjected to coercion by a higher authority, human organization has not evolved to give any institution sovereignty over the nation state. Solutions to global collective action problems must involve covenants (treaties) among states that are self-enforcing.

      To stabilize the climate, a treaty must get all states to (i) participate in and (ii) comply with an agreement that (iii) drives emissions to zero. The Paris Agreement, adopted at the 2015 summit, secures the first requirement, and possibly the second, but only because it is a voluntary agreement and will fall short of meeting the third requirement. The Montreal Protocol, negotiated in 1987 to protect the stratospheric ozone layer, meets all three requirements, thanks partially to a ban on trade in chlorofluorocarbons between parties to the protocol and nonparties. Because of the ban, once the vast majority of countries joined the agreement, all others wanted to join. William Nordhaus, a recipient of this year’s Nobel Memorial Prize in Economic Sciences, has recently analyzed a similar cure for climate change in which members of a “climate club” who agree to curb emissions impose a tariff on imports from nonmembers to encourage their participation. Unfortunately, his analysis shows that as the carbon tax rises to the level needed to stabilize the climate, participation in the club collapses.

      Breaking up the problem may provide more leverage for enforcement. The Kigali Amendment to the Montreal Protocol, adopted in December 2016, phases down hydrofluorocarbons, a group of greenhouse gases, and this will be effective in addressing this particular cause of climate change for the same reasons that the Montreal Protocol has been effective in protecting the ozone layer. Other climate agreements, adopted in parallel with the Paris Agreement, should be negotiated for individual sectors, such as aluminum and steel and international aviation and shipping, all linked to trade.

      However, the time has come to contemplate other, more radical solutions. The October 2018 Intergovernmental Panel on Climate Change special report concluded that limiting temperature change to 1.5°C cannot be achieved by simply curbing emissions, but requires removing CO2 from the atmosphere. The only true “backstop” for limiting climate change is removal of CO2 by industrial processes, which converts the problem from one of changing behavior into one of joint financing of a large-scale project. Another option, solar geoengineering, acts directly on global mean temperature, but is considered risky. Of course, not using it could also be risky. In the end, regardless of pathways forward, we will have to choose between risks to address the scale of this problem and achieve, rather than merely aspire to, global collective action on climate change.

Ireland Slashes Peat Power to Lower Emissions

[These excerpts are from an article by Emily Toner in the 14 December 2018 issue of Science.]

      In Ireland, peat has been used for centuries to warm homes and fire whiskey distilleries. For a country with little coal, oil, and gas, peat—deep layers of partially decayed moss and other plant matter—is also a ready fuel for power plants. Peat power peaked in the 1960s, providing 40% of Ireland’s electricity. But peat is particularly polluting. Burning it for electricity emits more carbon dioxide than coal, and nearly twice as much as natural gas. In 2016, peat generated nearly 8% of Ireland’s electricity, but was responsible for 20% of that sector’s carbon emissions….

      …Bord na Mona, which supplies peat to the three remaining power stations burning it for electricity, announced in October that it would cut its peat supply for electricity by a third by 2020 and end it completely by 2027. Ireland will need to find alternative, lower carbon sources of electricity And approximately 60 bogs no longer needed for fuel will be converted back to wetlands or put to commercial uses such as land for wind farms.

      Behind the phaseout is Ireland's promise to the European Union to reduce greenhouse gas emissions by 20% in 2020, compared with 2005 levels….Despite rapid growth in wind power and increasingly energy efficient homes and vehicles, it will struggle to reduce emissions by even 1%...

      And replacing peat with biomass, as the power companies plan to do, is not a panacea. A decade ago, Bord na Mona began to cofuel a peat-burning station with mixtures of biomass including a grass called miscanthus, olive pits, almond shells, palm kernel shells, and beet pulp, much of it imported from all over the world. Because biomass takes up carbon from the atmosphere as it grows, the European Union counts it as a carbon-neutral, renewable resource—even though transportation, processing, and land-use costs make it less so….

      Rehabilitating the harvested peatlands, however, is a clear plus for climate. When bogs are drained to harvest peat, or for any other use, such as agriculture, grazing, or forestry, exposure to oxygen jump-starts the decomposition of the stored organic matter, releasing carbon into the atmosphere….

      …As a result, say ecologists, conserving peatlands has a triple benefit: reducing emissions from both power plants and exposed fields and, with restored plant life, sequestering more carbon in future peat deposits….

      Moreover, healthy peatlands improve water quality and provide needed habitat for threatened species such as curlews and marsh fritillary butterflies….

Why Modern Humans Have Round Heads

[These excerpts are from an article by Ann Gibbons in the 14 December 2018 issue of Science.]

      Ever since researchers first got a good look at a Neanderthal skull in the 1860s, they were struck by its strange shape: stretched from front to back like a football rather than round like a basketball, as in living people. But why our heads and those of our ice age cousins looked different remained a mystery.

      Now, researchers have found an ingenious way to identify genes that help explain the contrast. By analyzing traces of Neanderthal DNA that linger in Europeans from their ancestors’ trysts, researchers have identified two Neanderthal gene variants linked to slightly less globular head shape in living people….

      Cradle a newborn and you’ll see that infants start life with elongated skulls, somewhat like Neanderthals. It’s only when the modern human brain nearly doubles in size in the first year of life that the skull becomes globular….

Wake-up Call from Hong Kong

[These excerpts are from an editorial by Victor J. Dzau, Marcia McNutt and Chunli Bai in the 14 December 2018 issue of Science.]

      The Second International Summit on Human Genome Editing, held in Hong Kong last month, was rocked by the revelation from a researcher from She nzhen that twins were born whose healthy embryonic genomes had been edited to confer resistance to HIV Despite widespread condemnation by the summit organizing committee, world scientific academies, and prominent scientific leaders that such research was “deeply disturbing” and “irresponsible,” and the launch of an investigation in China into the researcher's actions, it is apparent that the ability to use CRISPR-Cas9 to edit the human genome has outpaced nascent efforts by the scientific and medical communities to confront the complex ethical and governance issues that they raise. The current guidelines and principles on human germline genome editing are based on sound scientific and ethical principles. However, this case highlights the urgent need to accelerate efforts to reach international agreement upon more specific criteria and standards that have to be met before human germline editing would be deemed permissible….

      To maintain the public's trust that someday genome editing will be able to treat or prevent disease, the research community needs to take steps now to demonstrate that this new tool can be applied with competence, integrity, and benevolence. Unfortunately, it appears that the case presented in Hong Kong might have failed on all counts, risking human lives as well as rash or hasty political reaction.

      To maintain the public's trust that someday genome editing will be able to treat or prevent disease, the research community needs to take steps now to demonstrate that this new tool can be applied with competence, integrity, and benevolence. Unfortunately, it appears that the case presented in Hong Kong might have failed on all counts, risking human lives as well as rash or hasty political reaction.

The Last of the Ocean Wilderness

[These excerpts are from an article by Kendall Jones and James Watson in the December 2018 issue of Scientific American.]

      The ocean covers more than 70 percent of our planet, an area of over 160 million square miles. It is so immense that explorers once thought there was no way to cross it. When our ships were advanced enough to do so, naturalists then thought it impossible for humans to ever exhaust fisheries or drive marine species to extinction.

      They were wrong.

      Commercial fishing now covers an area four times that of agriculture, and much of that expanse has Peen rendered completely unsustainable. We have depleted 90 percent of formerly important coastal species. Large fish have been harvested so heavily that they are virtually wiped out in many places. Indeed, studying once vital fish habitats such as coral reefs has been compared to trying to understand the Serengeti by studying termites and locusts while ignoring the wildebeest and lions.

      Some may hope that there are immense areas still untouched, given that humans do not live on the ocean and we need specialized ships to go far beyond the coast. But that is incorrect. In a study published this summer in Current Biology, we used fine-scale global data on 15 human stressors to the ocean—including commercial shipping, sediment runoff and several types of fishing—to show that Earth’s “marine wilderness” is dwindling. Just 13 percent of the ocean remains as wilderness, and in coastal regions, where human activities are most intense, there is almost no wilderness left at all. Of the roughly 21 million square miles of marine wilderness remaining, almost all is found in the Arctic and Antarctic or around remote Pacific island nations with low populations.

      These remnants of wilderness are home to unparalleled marine life, sustaining large predators and high levels of genetic diversity. The lack of human impact can also make them highly resilient to rising sea temperatures and coral bleaching—stressors that cannot be halted without globally coordinated efforts to reduce emissions.

      In an era of widespread marine biodiversity loss, wilderness areas also act like a window into the past, revealing what the ocean looked like before overfishing and pollution took their toll. This is crucial information for marine conservation….

      What concerns us now is that most wilderness remains unprotected. This means it could be lost at any time, as advances in technology allow us to fish deeper and ship farther than ever before. Thanks to a warming climate, even places that were once safeguarded because of year-round ice cover are now open to fishing and shipping.

      This lack of protection stems in large part from international environmental policies failing to recognize the unique values of wilderness, instead focusing on saving at-risk ecosystems and avoiding extinctions. This is akin to a government using its entire health budget on emergency cardiac surgery, without preemptive policies encouraging exercise to decrease the risk of heart attacks occurring in the first place.

      If Earth’s marine biodiversity is to be preserved in perpetuity it is time for conservation to focus not only on the E.R. but also on preventive health measures….

Rethinking the “Anthropocene”

[These excerpts are from an editorial in the December 2018 issue of Scientific American.]

      Alarming news, arriving almost daily, about rising temperatures, melting glaciers, species diebacks, radioactive waste, oceans contaminated with plastic, and other calamities has seared in our minds the staggering impact that humanity now has on our planet In 2000 atmospheric scientist Paul Crutzen encapsulated these concerns into a single word, the “Anthropocene,” which he proposed as the geologic name of an era dominated by the human race. Geologists cannot agree on when the Anthropocene began, and stratigraphers are still debating whether it is in fact a geologic era at all. Even so, the term has riveted public attention and sparked impassioned arguments about the relationship between humans and the natural world.

      Several scholars in the humanities criticize the name itself, however, arguing that it perpetuates long-standing misconceptions about this relationship. Replacing “Anthropocene” with a name that focuses instead on its underlying causes might be more conducive to helping us tackle them….

      A second indictment is that “Anthropoeene” implicitly blames the entire human race for a crisis caused by a relative few. Surely the “Man of the Hole,” the last survivor of an uncontacted hunter-gatherer tribe in the Brazilian Amazon, bears less responsibility for our present predicament than, say, former Secretary of State Rex Tillerson, who was CEO of ExxonMobil. The tribe’s carbon emissions are essentially zero, whereas ExxonMobil is the fifth largest carbon emitter in the world, according to the Carbon Majors Report.

      Yet another critique is that the “Anthropocene discourse” tends to hold not only all humans but human nature responsible for this predicament. That makes little sense to anthropologists, who point out that people have repeatedly figured out how to live within their ecological means and even thrive….

      …Working collaboratively, the natural sciences and the humanities can help us break through thought barriers and generate fresh ideas. To quote Albert Einstein: “We cannot solve our problems with the same thinking we used when we created them.”

“Half the Truth is often a Great Lie.” – Benjamin Franklin

[This editorial by John Seager is in the December 2018 issue of Population Connection.]

      By failing even to mention population growth in the thirty-three-page “Summary for Policymakers” of its new publication, Global Warming of 1.5°C, the Intergovernmental Panel on Climate Change (IPCC) offered less than the whole truth. This is despite the fact that a 2010 paper published in the Proceedings of the National Academy of Sciences concluded that by the end of the century, slower population growth could reduce total fossil filel emissions by 37-41 percent.

      The IPCC “Summary for Policymakers” finds room to call for ecosystem-based adaptation, ecosystem restoration, biodiversity management, sustainable aquaculture, efficient irrigation, social safety nets, disaster risk management, green infrastructure, sustainable land use, and water management. But not one single word about population stabilization.

      Ignoring the impacts of soaring population growth on climate change is like failing to mention the Himalayas while describing Nepal.

      Overpopulation remains the elephant in the room. Why the silence? The hard truth is that many experts worry they might offend someone, somewhere. This is a shameful betrayal of reason.

      What will they tell hundreds of millions fated to become stateless environmental refugees, pushed to relocate due to climate change? What will they say to subsistence farmers forced to watch their families starve as meager plots become arid wastelands? And what about the countless, voiceless species doomed to extinction because so many authorities tremble at the very possibility of a negative reaction?

      Benjamin Franklin, the redoubtable author of Poor Richard’s Almanack, warns, “You may delay, but time will not.”

      There is no excuse for timid temporizing in the face of a global crisis. When climate experts fail to address population growth — arguably the single biggest driver of climate change — they place far more than their own reputations at risk.

      What is so hard about letting the world know that if every woman and every couple had unfettered access to all reproductive health services, we'd see population challenges evaporate? Then maybe, just maybe, we’d have a fighting chance to save Earth as we know it. End this silence, now!

The Color Black

[These excerpts are from an article by Paul G. Hewitt in the November/December 2018 issue of The Science Teacher.]

      As science people we like to say that black is not a color—black is the absence of light. But try telling that to a paint specialist when you buy a can of black paint! Similarly, science people say that white is not a color unto itself but the combination of the colors that make up the rainbow. However, if the paint specialist doesn't have white paint, please don’t request that the colors red through violet be mixed! The mixing rules for pigments and lights are very different. In the painter’s world, black and white are legitimate colors.

      Roger King at City College of San Francisco contrasts black and white with his “light box”…. Students see the hole in the wooden box as black, which suggests a black interior. But is it black inside? Roger then opens the top…to show that the inside of the box is white. So why does the hole look black, when clearly the interior of the box is a bright white?

      …Light from the environment enters the hole in the box and is scattered inside by multiple reflections in all directions. An important feature of light is that a portion of it is always absorbed by the reflecting surface whenever reflection occurs. Reflection of light from a surface is never 100 percent; light intensity diminishes with each encounter with the box’s inner surface. The light that does exit the hole is much dimmer than the light that entered.

      Other examples of holes that appear black are open doorways or windows of distant houses in the daytime. Openings appear black because the light that enters them is reflected to and fro on the inside walls many times, and is partly absorbed with each reflection. As a result, very little of the light exits the openings and travels to our eyes….Open ends of pipes in a stack and the openings to caves all appear black as well.

      You may have noticed that some surfaces look darker when they are wet than when they are dry. Light rays incident on a wet surface undergo repeated reflections and absorptions inside the transparent wet region, enough to darken the net reflected light that reaches your eye.

Climate Change and Marine Mass Extinction

[These excerpts are from an article by Lee Kump in the 7 December 2018 issue of Science.]

      Voluminous emissions of carbon dioxide to the atmosphere, rapid global warming, and a decline in biodiversity-the storyline is modern, but the setting is ancient: The end of the Permian Period, some 252 million years ago. For the end-Permian, the result was catastrophic: the greatest loss of plant and animal life in Earth history. Understanding the details of how this mass extinction played out is thus crucial to its use as an analog for our future….

      A number of kill mechanisms for end-Permian extinction have been proposed, most triggered by the tremendous volcanic activity associated with the emplacement of the vast lava flows of the Siberian Traps, the eruption of which was coincident with the mass extinction. The Siberian Traps are estimated to have released tens of thousands of petagrams of carbon as carbon dioxide and methane, explaining the 10° to 15°C tropical warming revealed by oxygen isotope compositions of marine fossils. On land, unbearably hot temperatures and hypoxia likely were the main cause of mass extinction of plants and animals, although ultraviolet radiation exposure from a collapsed ozone shield contributed as well. Rapid warming also likely led to the loss of oxygen from the ocean’s interior, extending up onto the continental shelves—a conclusion supported both by the widespread distribution of indicators for marine anoxia in sedimentary rocks and by numerical modeling of the Permian ocean-atmosphere system.

      Once considered nonselective, mass extinc-ions are increasingly revealing patterns of differential impact across species, lifestyles, and geographic locations through their fossil records. A geographic pattern to Permian extinction, however, has remained elusive….

Taking Aim

[These excerpts are from an article by Meredith Wadman in the 7 December 2018 issue of Science.]

      …Guns are the second-leading cause of death of children and teens in the United States, after motor vehicle crashes….In 2016, the most recent year for which data are available, they killed nearly 3150 people aged 1 to 19, according to data from the Centers for Disease Control and Prevention (CDC) in Atlanta. Cancer killed about 1850. But this year, the National Institutes of Health (NIH) 'in Bethesda, Maryland, spent $486 million researching pediatric cancer and $4.4 million studying children and guns….

      That's because gun violence research has been operating under a chill for more than 2 decades. In 1996, Congress crafted an amendment, named for its author, then-Arkansas Representative Jay Dickey (R), preventing CDC—the government’s lead injury prevention agency—from spending money “to advocate or promote gun control.”

      That law was widely interpreted as banning any CDC studies that probe firearm violence or how to prevent it. The agency’s gun injury research funding was quickly zeroed out, and other health agencies grew wary. The few dozen firearm researchers who persisted were forced to rely on modest amounts from other agencies or private funders…to tackle a massive problem.

      Now, there may be early signs of a thaw. In March, in the wake of the mass shooting at a Parkland, Florida, high school, Congress wrote that CDC is free to probe the causes of gun violence, despite the Dickey amendment. The agency has not done so, citing a lack of money.) And annual firearm-related funding from NIH…roughly tripled after a 2013 presidential directive that was issued in the wake of the mass shooting at Sandy Hook Elementary School in Newtown, Connecticut. Just as importantly, the agency began to flag firearm violence in some of its calls for research.

      …And last month, the National Rifle Association (NRA) in Fairax, Virginia, provoked a firestorm when it tweeted that “self-important anti-gun doctors” should “stay in their lane.” Hundreds of emergency department doctors tweeted back, many including photographs of their scrubs, hands, and shoes bloodied from treating gunshot victims. More than 40,000 health care professionals…signed an open letter to NRA complaining that the group has hobbled gun violence research, declaring, “This is our lane!”

      All the same, there’s still little public money for gun research….

Chess, a Drosophila of Reasoning

[These excerpts are from an editorial by Garry Kasparov in the 7 December 2018 issue of Science.]

      Much as the Drosophila melanogaster fruit fly became a model organism for geneticists, chess became a Drosophila of reasoning. In the late 19th century Alfred Binet hoped that understanding why certain people excelled at chess would unlock secrets of human thought. Sixty years later, Alan Turing wondered if a chess-playing machine might illuminate, in the words of Norbert Wiener, “whether this sort of ability represents an essential dif-ference between the poten-tialities of the machine and `the mind.”

      Much as airplanes don’t flap their wings like birds, machines don’t generate chess moves like humans do. Early programs that attempted it were weak. Success came with the “minimax” algorithm and Moore’s law, not with the ineffable human combination of pattern recognition and visualization. This prosaic formula dismayed the artificial intelligence (AI) crowd, who realized that profound computational insights were not required to produce a machine capable of defeating the world champion.

      But now the chess fruit fly is back under the microscope….AlphaZero starts out knowing only the rules of chess, with no embedded human strategies. In just a few hours, it plays more games against itself than have been recorded in human chess history. It teaches itself the best way to play, reevaluating such fundamental concepts as the relative values of the pieces. It quickly becomes strong enough to defeat the best chess-playing entities in the world, winning 28, drawing 72, and losing none in a victory over Stockfish.

      …Programs usually reflect priorities and prejudices of programmers, but because AlphaZero programs itself, I would say that its style reflects the truth. This superior understanding allowed it to outclass the world's top traditional program despite calculating far fewer positions per second. It’s the embodiment of the cliche, “work smarter, not harder?”

      AlphaZero shows us that machines can be the experts, not merely expert tools….

      Machine learning systems aren't perfect, even at a closed system like chess. There will be cases where an Al will fail to detect exceptions to their rules. Therefore, we must work together, to combine our strengths. I know better than most people what it’s like to compete against a machine. Instead of raging against them, it’s better if we're all on the same side.

Leon Max Lederman (1922-2018)

[These excerpts are from an article by Rocky Kolb in the 30 November 2018 issue of Science.]

      …Leon’s group used the Nevis accelerator to discover nonconservation of parity in muon decay. Remarkably, they conceived of the idea during the half-hour drive from the main campus to Nevis one Friday, constructed the experiment that evening, and collected the data by the end of the weekend, demonstrating clear evidence for the fundamental result.

      In 1962, Leon and his colleagues led a team that established the existence of a second-generation neutrino, the muon neutrino. He would share the Nobel Prize in recognition of this work. In addition to the importance of the two-neutrino result in the development of the standard model of particle physics, the experiment pioneered the use of neutrino beams to study weak interactions.

      In the 1970s, Leon’s interests turned to particles produced at high transverse momentum in high-energy proton-proton collisions. A sequence of ever-higher-energy experiments at Brookhaven, the Intersecting Storage Ring at CERN, and finally at Fermilab culminated in the 1977 discovery of the bottom quark, one of six known quarks. Shortly afterward, Leon became the second director of Fermilab. During his three decades as an experimental particle physicist, he supervised 50 Columbia University Ph.D. candidates and was a mentor to many other young students and postdocs….

      …In addition to scientific leadership, with characteristic charm and humor, Leon transformed Fermilab from a frontier outpost in the cornfields of Illinois into a cosmopolitan center for science and science education.

      As a professor at Columbia University, Leon reached many generations of undergraduates in his “physics for poets” class. He transposed his love of teaching to Fermilab, where he instigated Saturday Morning Physics, a weekend class for area high-school students featuring lectures by Leon and other Fermilab scientists. He also started a public education and outreach effort at Fermilab directed toward precollege students. Beyond Fermilab, Leon was a founder of a residential state-sponsored high school for science and mathematics and a Chicago-based teacher academy for math and science. His leadership in education and outreach inspired physicists to communicate with the public. The author of several books for the general public, including The God Particle, Leon wrote with the same humor, wit, and charm that drew people to his public lectures. He had no equal f in communicating the joys of physics.

Define the Human Right to Science

[These excerpts are from an article by Jessica M. Wyndham and Margaret Weigers Vitullo in the 30 November 2018 issue of Science.]

      The adoption of the Universal Declaration of Human Rights (UDHR) by the United Nations (UN) General Assembly will mark its 70th anniversary on 10 December. One right enshrined in the UDHR is the right of everyone to “share in scientific advancement and its benefits.” In 1966, this right was incorporated into the International Covenant on Economic, Social and Cultural Rights, a treaty to which 169 countries have voluntarily agreed to be bound. Unlike most other human rights, however, the right to science has never been legally defined and is often ignored in practice by the governments bound to implement it. An essential first step toward giving life to the right to science is for the UN to legally define it….

      The scientific community has contributed three key insights to the ongoing UN process. One is that the right to science is not only a right to benefit from material products of science and technology. It is also a right to benefit from the scientific method and scientific knowledge, whether to empower personal decision-making or to inform evidence-based policy. In addition, access to science needs to be understood as nuanced and multifaceted. People must be able to access scientific information, translated and actionable by a nonspecialist audience. Scientists must have access to the materials necessary to conduct their research, and access to the global scientific community. Essential tools for ensuring access include science education for all, adequate funding, and an information technology infrastructure that serves as a tool of science and a conduit for the diffusion of scientific knowledge. Also, scientific freedom is not absolute but is linked to and must be exercised in a manner consistent with scientific responsibility.

      …Three of the most important questions were: What should be the relationship between the right to benefit from science and intellectual property rights? How should government obligations under the right differ based on the available national resources? What is scientific knowledge and how should it be differentiated, if at all, from traditional knowledge?

      …The effort to define the right must not become mired in demands to resolve questions a priori that can only be answered over time. Insights from the scientific and engineering communities provide responses to many of the questions. Civil society must continue to illustrate how the right to science complements existing human rights protections. The scientific community, particularly in the 169 countries bound to implement the right, Margaret Weigers must demonstrate how the right can be instantiated a within their own national contexts….

      The power and potential of the right to science for empowering individuals, strengthening communities, and improving the quality of life can hardly be overstated. It is time for the UN process to reach a responsible and productive end and for the right to science to be put into practice as was intended when it was first recognized by the United Nations in 1948.

Climate Impacts Worsen, Agencies Say

[This brief article by Jeffrey Brainard is in the 30 November 2018 issue of Science.]

      In a stark display of the U.S. political tensions surrounding global warming, President Donald Trump’s administration is dismissing a major report, written by the government’s own experts, which warns that climate change poses a serious and growing threat to the nation’s economic and environmental health. More than 300 specialists contributed to the 1600-page report, formally known as Volume II of the Fourth National Climate Assessment, released 23 November by federal agencies. It warns that worsening heat waves, coastal flooding, wildfires, and other climate-related impacts are already afflicting the United States and could reduce its economic output by 10% in coming decades. But White House officials down-played such findings, claiming they are based on outdated climate models and “the most extreme” warming scenario. Despite the report, the administration says it has no plans to alter its efforts to weaken policies aimed at curbing climate change. Meanwhile, the World Meteorological Organization reported on 20 November that atmospheric concentrations of carbon dioxide, a primary warming gas, reached a global average of 405.5 parts per million (ppm) in 2017, up from 403.3 ppm in 2016. Many scientists believe concentrations will need to remain below 450 ppm to avoid catastrophic warming.

A Rigged Economy

[These excerpts are from an article by Joseph E. Stiglitz in the November 2018 issue of Scientific American.]

      The notion of the American Dream—that, unlike old Europe, we are a land of opportunity—is part of our essence. Yet the numbers say otherwise. The life prospects of a young American depend more on the income and education of his or her parents than hi almost any other advanced country. When poor-boy-makes-good anecdotes get passed around in the media, that is precisely because such stories are so rare.

      Things appear to be getting worse, partly as a result of forces, such as technology and globalization, that seem beyond our control, but most disturbingly because of those within our command. It is not the laws of nature that have led to this dire situation: it is the laws of humankind. Markets do not exist in a vacuum: they are shaped by rules and regulations, which can be designed to favor one group over another. President Donald Trump was right in saying that the system is rigged—by those in the inherited plutocracy of which he himself is a member. And he is making it much, much worse.

      America has long outdone others in its level of inequality, but in the past 40 years it has reached new heights. Whereas the income share of the top 0.1 percent has more than quadrupled and that of the top 1 percent has almost doubled, that of the bottom 90 percent has declined. Wages at the bottom, adjusted for inflation, are about the same as they were some 60 years ago! In fact, for those with a high school education or less, incomes have fallen over recent decades. Males have been particularly hard hit, as the U.S. has moved away from manufacturing industries into an economy based on services.

      Wealth is is even less equally distributed, with just three Americans having as much as the bottom 50 percent—testimony to how much money there is at the top and how little there is at the bottom. Families in the bottom 50 percent hardly have the cash reserves to meet an emergency. Newspapers are replete with stories of those for whom the breakdown of a car or an illness starts a downward spiral from which they never recover….

      Defenders of America’s inequality have a pat explanation. They refer to the workings of a competitive market, where the laws of supply and demand determine wages, prices and even interest rates—a mechanical system, much like that describing the physical universe. Those with scarce assets or skills are amply rewarded, they argue, because of the larger contributions they make to the economy. What they get merely represents what they have contributed. Often they take out less than they contributed, so what is left over for the rest is that much more.

      This fictional narrative may at one time have assuaged the guilt of those at the top and persuaded everyone else to accept this sorry state of affairs. Perhaps the defining moment exposing the lie was the 2008 financial crisis, when the bankers who brought the global economy to the brink of ruin with predatory lending, market manipulation and various other antisocial practices walked away with millions of dollars in bonuses just as millions of Americans lost their jobs and homes and tens of millions more worldwide suffered on their account. Virtually none of these bankers were ever held to account for their misdeeds.

      ….At the time of the Civil War, the market value of the slaves in the South was approximately half of the region’s total wealth, including the value of the land and the physical capital—the factories and equipment. The wealth of at least this part of this nation was not based on industry, innovation and commerce but rather on exploitation. Today we have replaced this open exploitation with more insidious forms, which have intensified since the Reagan-Thatcher revolution of the 1980s. This exploitation, I will argue, is largely to blame for the escalating inequality in the U.S.

      After the New Deal of the 1930s, American inequality went into decline. By the 1950s inequality had receded to such an extent that another Nobel laureate in economics, Simon Kuznets, formulated what came to be called Kuznets's law. In the early stages of development, as some parts of a country seize new opportunities, inequalities grow, he postulated; in the later stages, they shrink. The theory long fit the data—but then, around the early 1980s, the trend abruptly reversed.

      …Overall, wages are likely to be far more widely dispersed in a service economy than in one based on manufacturing, so the transition contributes to greater inequality. This fact does not explain, however, why the average wage has not improved for decades. Moreover, the shift to the service sector is happening in most other advanced countries: Why are matters so much worse in the U.S.?

      Again, because services are often provided locally, firms have more market power: the ability to raise prices above what would prevail in a competitive market. A small town in rural America may have only one authorized Toyota repair shop, which virtually every Toyota owner is forced to patronize. The providers of these local services can raise prices over costs, increasing their profits and the share of income going to owners and managers. This, too, increases inequality. But again, why is US. inequality practically unique?

      …In the U.S., the market power of large corporations, which was greater than in most other advanced countries to begin with, has increased even more than elsewhere. On the other hand, the market power of workers, which started out less than in most other advanced countries, has fallen further than elsewhere. This is not only because of the shift to a service-sector economy—it is because of the rigged rules of the game, rules set in a political system that is itself rigged through gerrymandering, voter suppression and the influence of money. A vicious spiral has formed: economic inequality translates into political inequality, which leads to rules that favor the wealthy, which in turn reinforces economic inequality.

      …We are already paying a high price for inequality, but it is just a down payment on what we will have to pay if we do not do something—and quickly. It is not just our economy that is at stake; we are risking our democracy.

      As more of our citizens come to understand why the fruits of economic progress have been so unequally shared, there is a real danger that they will become open to a demagogue blaming the country’s problems on others and making false promises of rectifying “a rigged system.” We are already experiencing a foretaste of what might happen. It could get much worse.

Dereliction of Duty

[This editorial is in the November 2018 issue of Scientific American.]

      There are several hundred people in Washington, D.C., paid with taxpayer dollars, who are not doing their jobs. This November we have the chance to do something about that because these people are members of the U.S. Congress, and in upcoming elections, they can be replaced with representatives who will live up to their responsibilities.

      Those responsibilities, set out by the Constitution, include oversight of the executive branch, in this case the Trump administration. That administration's agencies are supposed to craft policies based, in part, on good evidence and good science. For the past 21 months, many of them have not. Yet Congress has refused to hold them accountable.

      Exhibit A is the Environmental Protection Agency. Its mission, the agency says, is “to protect human health and the environment ... based on the best available scientific information.” Instead the EPA has ignored scientific evidence to justify lowering power plant emissions and greenhouse gas targets; made it more difficult for people to learn about potentially dangerous chemicals in their communities; replaced independent scientists on advisory boards with people connected to businesses the agency is supposed to regulate; and tried to make it harder to use science as a basis for regulations to protect human health.

      During all of this, Congress has done next to nothing.

      Consider what happened this past spring, when EPA director Scott Pruitt, who has since resigned amid a dozen ethics investigations, proposed that no research could be used to form environmental policy unless all data connected to it were publicly available. He said this proposed rule would ensure transparency. It was really a transparent effort to ignore science.

      Specifically, it would ignore research that links industrial pollution to human health. These studies include confidential patient data, such as names, addresses, birthdays and health problems—data that were only provided by patients under a guarantee of privacy. The Six Cities study, begun in the 1970s, was the first research to show that particulate matter in the air hurts and kills people. It has been replicated several times. But because its publications do not include all private patient data, the study would be ignored by the EPA when it considers permissible pollution levels. The World Health Organization estimates that this kind of pollution, largely from minute particulates, kills three million people worldwide every year. For these reasons, the rule has been condemned by every major health and science group.

      There were two congressional hearings involving the EPA after this rule was proposed. The House Committee on Energy and Commerce’s environmental subcommittee interviewed Pruitt, starting off with the chair, Republican Representative John Shimkus of Illinois, stating he was “generally pleased” with what the agency was doing. The senior minority member, Democratic Representative Paul Tonko of New York, did voice concerns about science, but the focus of the hearing remained elsewhere. In the Senate, an appropriations subcommittee gave Pruitt a much tougher time on his personal ethics but also spent almost no effort on science.

      Pruitt has departed, but there is no reason to think that his antiscience approach has gone with him. The healthstudiesrule is still under active consideration. Further, the EPA announced looser power plant standards this August despiteHdmitting, in its own document, that the extra pollution would lead to 1,400 additional deaths in the U.S. each year.

      Similar evidence-free approaches have taken hold at the Department of the Interior, which is scuttling a wildfire-eghting science program whose discoveries help firefighters save lives by forecasting the direction of infernos. The Department of Energy has stopped a set of new efficiency standards for gas furnaces and other appliances. Congress has been quiet.

      Congressional committees work by majority rule, so if the Republicans in the current majority do not want to hold hearings or use their control over agency budgets to compel changes, there are none. But the American people can make a change. The entire House of Representatives and one third of the Senate are up for reelection right now (except for those who are retiring). We can, with our votes, make them do their jobs.

Artificial Wood

[These excerpts are from an article by Sid Perkins in the November 2018 issue of Scientific American.]

      A new lightweight substance is as strong as wood yet lacks its standard vulnerabilities to fire and water.

      To create the synthetic wood, scientists took a solution of polymer resin and added a pinch of chitosan, a sugar polymer derived from the shells of shrimp and crabs. They freeze-dried the solution, yielding a structure filled with tiny pores and channels supported by the chitosan. Then they heated the resin to temperatures as high as 200 degrees Celsius to cure it, forging strong chemical bonds.

      The resulting material…is as crush-resistant as wood….

      Unlike natural wood, the new material does not require years to grow. Moreover, it readily repels water—samples soaked in water and in a strong acid bath for 30 days scarcely weakened, whereas samples of balsa wood tested under similar conditions lost two thirds of their strength and 40 percent of their crush resistance. The new material was also difficult to ignite and stopped burning when it was removed from the flame.

      …Its porosity lends an air-trapping capacity that could make it suitable as an insulation for buildings….

Kids these Days

[These excerpts are from an article by Michael Shermer in the December 2018 issue of Scientific American.]

      …suicide rates increased 46 percent between 2007 and 2015 among 15- to 19-year-olds. Why are iGeners [members of the Internet Generation] different from Millennials, Gen Xers and Baby Boomers?

      Twenge attributes the malaise primarily to the widespread use of social media and electronic devices, noting a positive correlation between the use of digital media and mental health problems. Revealingly, she also reports a negative correlation between lower rates of depression and higher rates of time spent on sports and exercise, in-person social interactions, doing homework, attending religious services, and consuming print media, such as books and magazines. Two hours a day on electronic devices seems to be the cutoff, after which mental health declines, particularly for girls who spend more time on social media, where FOMO (“fear of missing out”) and FOBLO (“fear of being left out”) take their toll….This, after noting that the percentage of girls who reported feeling left out increased from 27 to 40 between 2010 and 2015, compared with a percentage increase from 21 to 27 for boys.

      …iGeners have been influenced by their overprotective “helicoptering” parents and by a broader culture that prioritizes emotional safety above all else. The authors identify three “great untruths”:

      1. The Untruth of Fragility: “What doesn’t kill you makes you weaker?”

      2. The Untruth of Emotional Reasoning: “Always trust your feelings?”

      3. The Untruth of Us versus Them: “Life is a battle between good people and evil people.”

      Believing that conflicts will make you weaker, that emotions are a reliable guide for responding to environmental stressors instead of reason and that when things go wrong, it is the fault of evil people, not you, iGeners are now taking those insalubrious attitudes into the workplace and political sphere….

      Solutions? “Prepare the child for the road, not the road for the child” is the first folk aphorism Lukianoff and Haidt recommend parents and educators adopt. “Your worst enemy cannot harm you as much as your own thoughts, unguarded” is a second because, as Buddha counseled, “once mastered, no one can help you as much.” Finally, echoing Aleksandr Solzhenitsyn, “the line dividing good and evil cuts through the heart of every human being,” so be charitable to others.

      Such prescriptions may sound simplistic, but their effects are measurable in everything from personal well-being to societal harmony. If this and future generations adopt these virtues, the kids are going to be alright.

Income Inequality and Homicide

[These excerpts are from an article by Maia Szalavitz in the November issue of Scientific American.]

      Income inequality can cause all kinds of problems across the economic spectrum—but perhaps the most frightening is homicide. Inequality—the gap between a society’s richest and poorest—predicts murder rates better than any other variable....It is more tightly tied to murder than straight-forward poverty, for example, or drug abuse. And research conducted for the World Bank finds that both between and within countries, about half the variance in murder rates can be accounted for by looking at the most common measure of inequality….

      Another possible explanation is that as richer people retreat into ever more exclusive communities, their virtual disappearance masks rises in local inequality that are felt by former neighbors. A society in which millions struggle to pay their student loans and make a decent living while watching U.S. secretary of education Betsy DeVos—a woman of enormous wealth—cut the education budget and protect predatory for-profit schools is unlikely to be a safe and stable one. When men have little hope of a better future for either themselves or their kids, fights over what little status they have left take on outsize power. To break the cycle, everyone must recognize that it is in no one’s interest to escalate such pain.

The Decline of Africa’s Largesy Mammals

[These excerpts are from an article by Rene Bobe and Susana Carvalho in the 23 November 2018 issue of Science.]

      The human species is causing profound climatic, environmental, and biotic disruptions on a global scale. In the present time (now called the Anthropocene), most species of large terrestrial herbivores are threatened with extinction as their populations decline and their geographic ranges collapse under the pressure of human hunting, poaching, and encroachment. Although the scale of on-going anthropogenic ecological disruptions is unprecedented, human-driven extinctions are not new: There is strong evidence that humans played a major role in the wave of megafaunal losses at the end of the Pleistocene, between about 10,000 and 50,000 years ago. But when did humans, or our ancestors, begin to have such a profound effect on large herbivores to the point of causing extinctions?...

      Hominins—species on our side of the evolutionary divergence that separated us from the chimpanzees—first appeared in Africa in the late Miocene, about 7 million years ago. The late Miocene was a time of global climatic and environmental change, with an expansion of grasslands…in tropical latitudes and an increasing frequency of fires. At that time, large mammals were abundant in eastern Africa. At Lothagam, for example, in the Turkana Basin of Kenya, there were 10 species of megaherbivores, including the earliest records of the elephant family, Elephantidae. Near Lothagam is the early Pliocene site of Kanapoi, with a rich fossil record dated to about 4.2 million years ago. Kanapoi has the earliest record of the hominin genus Australopithecus, which coexisted with at least 11 species of megaherbivores: five proboscideans, two rhinocerotids, two giraffids, and two hippopotamids, along with a diverse fauna of large carnivores that included giant otters, hyenas, two species of saber-tooth felids, and three species of crocodiles. Kanapoi, at about 4.2 million years ago, with an area of 32 km2, had twice the number of megaherbivore species as the entire continent of Africa has today. Among the five species of proboscideans, there were the ancestors of the modern African and Asian elephants, Loxodonta and Elephas, respectively. From their first appearance in eastern Africa, both elephants fed predominantly on increasingly abundant grasses. It is probable that these elephants and other megaherbivores played a beneficial role for early hominins by opening up wooded environments, thereby result-ing in the mix of woodlands and grasslands where hominins seemed to thrive….

Cracking the Cambrian

[These excerpts are from an article by Joshua Sokol in the 23 November 2018 issue of Science.]

      …During the Cambrian, which began about 540 million years ago, nearly all modern animal groups—as diverse as mollusks and chordates—leapt into the fossil record. Those early marine animals exhibited a dazzling array of body plans, as though evolution needed to indulge a creative streak before buckling down. For more than a century, scientists have struggled to make heads or tails—sometimes literally—of those specimens, figure out how they relate to life today, and understand what fueled I the evolutionary explosion….

      Other sites around the world are also opening new vistas of the Cambrian. Scientists can now explore the animal explosion with a highlight reel of specimens, along with results from new imaging technologies and genetic and developmental stud-ips of living organisms….Researchers may be closer than ever to fitting these strange creatures into their proper places in the tree of life—and understanding the “explosion” that birthed them.

      Each new find brings the simple joy of unearthing and imagining a seemingly alien creature….

      How Cambrian species are related to today’s animals has been debated since the fossils first came to light. Walcott classified his oddities within known groups, noting that some Burgess Shale fossils, such as the brachiopods, persisted after the Cambrian or even into the present. So, for example, he concluded almost all the creatures resembling today’s arthropods were crustaceans.

      But later paleontologists had other ideas. Harvard University's Stephen Jay Gould perhaps best captured the charisma of Cambrian life in his 1989 book Wonderful Life: The Burgess Shale and the Nature of History, in which he lavished attention on the “weird wonders” excavated from Walcott’s city block-size quarry Gould argued that oddballs such as the aptly named Hallueigenia, a worm with legs and hard spines, seem unrelated to later animals. He slotted the unusual forms into their own phyla and argued that they were evolution's forgotten experiments, later cast aside by contingencies of fate.

      Contemporary paleontologists have settled on yet another way to understand them. Consider the arthropods, arguably Earth's most successful animals. In a family tree, the spray of recent branches that end in living arthropods—spiders, insects, crustaceans—constitutes a “crown” group. But some animals in the Burgess Shale probably come from earlier “stems” that branched off before the crown arthropods. These branches of the tree don’t have surviving descendants, like a childless great-uncle grinning out from a family photo. In that view, many of Gould's weird wonders are stem group organisms, related to the ancestors of current creatures although not ancestors themselves. Newer fossils from the Canadian Rockies help support that view. Caron argued in 2015, for example, that his specimens of Hallueigenia have features suggesting the animal belongs on a stem group of the velvet worms, creatures that still crawl around in tropical forests spitting slime….

      Bold claims that use anatomy to revise family trees engender similar controversy throughout the field. One argument that Hallueigenia fits with the velvet worms, for example, depends on the exact shape of its claws. But other teams counter that the claws aren’t diagnostic of ancestry.

      The uncertainties leave paleontologists ever hungry for newer, better specimens….

      Although show-stopping animals keep falling out of the strata, the full significance of the Cambrian explosion remains a mystery. Arthropods, the most diverse and common creatures known from the time, littered Cambrian ecosystems….the Cambrian witnessed both the birth and step-by-step diversification of many modern groups. Another approach yields a different answer, however. Geneticists use a tool called molecular clocks to trace back down the tree of life. By starting with genetic differences between living animals, which have accrued as a result of random mutations over the eons, molecular clocks can rewind time to the point where branches diverged.

      According to recent studies using that method, modem animals began to march off into their separate phyla some 100 million years before the Cambrian. The finding implies that those groups then hung out, inconspicuous or unnoticed in the fossil record, before suddenly stepping on stage.

      Paleontologists have a cryptic set of clues about life before the explosion. Long before the odd beasts of the Cambrian evolved, an even more alien set of ocean organisms left impressions on sedimentary rocks now seen in Namibia and Australia. The Ediacarans, as those fossils are called, taunt paleontologists with the same kind of interpretive challenge as the Cambrian’s weird wonders. But they’re even weirder. Their imprints suggest some grew in fractal patterns; others had three-part symmetry. Unhelpfully, they don’t have obvious mouths, guts, or appendages.

      …Caron and others keep hunting for fossil features that could reveal the relationships among Ediacaran, Cambrian, and present-day groups. Other researchers struggle to explain what caused the explosion of animal forms. Atmospheric oxygen may have spiked, enabling animals to grow bigger, stronger, and more active. Or erosion could have dumped toxic calcium into the oceans, prompting organisms to shunt it into building hard skeletons.

      Or biology itself could have led the way. Inventions such as predation, free swimming, and burrowing into the sea floor—all first seen in or shortly before the Cambrian—could have transformed a placid global ecology into a high-stakes contest, spurring waves of call-and-response innovation between groups. The explosion might also mark the moment when, after millions of years of quiet progress, animals had finally accrued the developmental recipes to build body parts and improvise on basic themes….Or, of course, multiple causes could have piled up together.

Fire and Rain

[These excerpts are from an editorial by Steve Metz in the November/December 2018 issue of The Science Teacher.]

      In the summer of 2018 a prolonged heat wave turned northern Europe brown. Sweden, Greece, and dozens of other European countries were ablaze with uncharacteristic wildfires, while states in the western U.S. experienced some of the largest fires in their history. Torrential rains flooded areas from California to Connecticut. Hurricane Florence dropped a meter of rain on the Carolinas, causing the Cape Fear River to crest at almost 19 meters (62 feet)….

      …Levels of atmospheric carbon dioxide reached 407 parts per million in August this year, tip over 20% in the past 40 years, and now higher than any time in at least the past 800,000 years. The last time atmospheric CO, concentrations were this high was more than three million years ago, when the temperature was 2°-3°C higher than during the pre-industrial era, and sea level was 15-25 meters higher than today….

      The effect of global warming on individual weather events is difficult to determine. Still, an emerging area of science—sometimes called “event attribution”—is rapidly advancing our understanding of the links between specific extreme events and human-caused climate change. For example, researchers estimated that “human interference in the climate system” increased Hurricane Florence’s rainfall forecast by over 50% and the storm’s projected diameter by about 80 kilometers….

      The events of summer 2018 warn us that climate change is not a far-off event. Global warming is real, it is caused mainly by human activity, and it is here now. Teachers must stand up for evidence-based climate science. We need to provide students with the accurate knowledge that can prepare and inspire them to take action on a personal, community, and global level.

A Physicist’s Final Reflections

[This excerpt is from an article by Andrew Robinson in the 16 November 2018 issue of Science.]

      …begins with Einstein. “Where did his ingenious ideas come from?” asks Hawking. He answers, “A blend of qualities, perhaps: intuition, originality, brilliance. Einstein had the ability to look beyond the surface to reveal the underlying structure. He was undaunted by common sense, the idea that things must be the way they seemed. He had the courage to pursue ideas that seemed absurd to others. And this set him free to be ingenious, a genius of his time and every other.”

      Was Hawking a genius, too? He never won a Nobel Prize, and the book gives no indication that Hawking regarded himself as a genius. On the other hand, he was one of the very few scientists since Einstein to become a household name….

Whose Science? A New Era in Regulatory “Science Wars”

[This excerpt is from an article by Wendy Wagner, Elizabeth Fisher and Pasky Pascual in the 9 November 2018 issue of Science.]

      …the reforms generally take the form of legislation or regulation, they do not simply suggest best practices for conducting scientific analyses but establish legal lines that cannot be crossed. Moreover, even though they create legal ground rules for scientific deliberations, the reforms have not been developed by the scientific community, but by members of Congress and political officials. In providing a birds’-eye view of the legal developments in regulatory science over the past 50 years, we identify just how idiosyncratic these current reforms are and why the scientific community needs to be aware of their implications.

      Although the agency’s underlying scientific analysis is often subject to scrutiny by stakeholders and political officials and review by the courts, these new proposals cut deeper and dictate in part how the formative scientific assessments themselves must be done. For example, these proposals require the exclusion of potentially relevant research during agencies’ initial review of the literature, dictate the types of computational models that must be considered in analyzing that information, and exclude respected scientists from peer reviewing the analysis. If the agency does not respect these legal lines, the agency’s review of the scientific literature is legally invalid and technically illegal. This contrasts with present practice where norms governing scientific analyses are rebuttable and subject to modification in light of specific contexts and scientific progress. The proposals thus reach down to control and limit the scientific record.

      The scientific community has been vocal in pointing out how the rules diverge from normal scientific practices, even while the legal requirements—some of which are still proposed and others which are final—purport to advance common goals, like data transparency and reproducibility….

Early Mongolians Ate Dairy but Lacked the Gene to Digest It

[These excerpts are from an article by Andrew Curry in the 9 November 2018 issue of Science.]

      More than 3000 years ago, herds of horses, sheep, and cows or yaks dotted the steppes of Mongolia. Their human caretakers ate the livestock and honored them by burying the animal bones with their own. Now, analysis of deposits on ancient teeth shows that early Mongolians milked their animals as well. That may not seem surprising. But the DNA of the same ancient individuals shows that as adults they lacked the ability to digest lactose, a key sugar in milk.

      The findings deepen an emerging puzzle, challenging an oft-told tale of how people evolve lactase persistence, the ability to produce a milk-digesting enzyme as adults….

      Most people in the world lose the ability to digest lactose after childhood. But in pastoralist populations, the story went, culture and DNA changed hand in hand. Mutations that allowed people to digest milk as adults would have given their carriers an advantage, enabling them to access a rich, year-round source of fat and protein. Dairying spread along with the adaptation, explaining why it is common in herding populations in Europe, Africa, and the Middle Fast.

      But a closer look at cultural practices around the world has challenged that picture. In modern Mongolia, for example, traditional herders get more than a third of their calories from dairy products. They milk seven kinds of mammals, yielding diverse cheeses, yogurts, and other fermented milk products, including alcohol made from mare’s milk….

      Geneticists are going back to the drawing board to understand why lactase persistence is common—and apparently selected for—in some dairying populations but absent in others….

      How dairying reached Mongolia is also a puzzle. The Yamnaya’s widespread genetic signature shows they replaced many European and Asian Bronze Age populations. But they seem to have stopped at the Altai Mountains west of Mongolia….

Facing Hatred

[These excerpts are from an editorial by Jose-Alain Sahel in the 9 November 2018, issue of Science.]

      …Two weeks ago, the mass killing at a Pittsburgh synagogue proved what I knew but wanted to forget—that no place on Earth is “safe” from hatred. But regardless of where any one of us lives and works, we are faced with the same, immense challenge: The quest for facts, enlightenment, and care versus ignorance and hatred matters more than ever.

      In the early 1930s, Albert Einstein asked Sigmund Freud to contribute to an initiative launched by the League of Nations that sought prominent individuals to promote peace and its values. Their exchange, written under the title Why War?, fell short of finding ways to counteract violence. It was published after Hitler had already been appointed chancellor. The rest is history. Should we simply believe that today there is a new cycle of history taking place? Moreover, in contrast to the League of Nations, nobody is asking the scientific community for help today. Science, with its fundamental quest for truth, or at least facts, and its open discourse, seems to have lost its iconic status, despite its contributions to societal well-being. The scientific community should not passively watch the disastrous rise of hatred worldwide.

      We are tasked with building a society of knowledge and care, where truth, integrity, and respect for all prevail. The heartening responses of health care providers to incidents in the United States and France epitomize this ideal. In 2015, after the mass killing at the Bataclan theater in Paris, nurses and physicians spontaneously converged on hospitals to help the victims, limiting the massive toll of the attacks. Likewise, in Pittsburgh, nurses and physicians treated the wounded, including the presumed killer, with efficiency and humanity. Helplines offering information and support were set up for a whole city in mourning. Religious and political leaders of all faiths and backgrounds, and community members from across the cultural spectrum, were united against hatred. In both cities, the responses were deeply rooted in society’s best, most inspiring traits….

      Caring means that each life matters, and that we all can and should be supported to grow and give back to society. The French Jewish philosopher Emmanuel Levinas asserted that looking into the face of one's fellow man invokes the imperative: “Thou shalt not kill.” This sounds naive and far too simplistic in the face of guns and strongly held prejudices. Yet, is there anything else in the world more meaningful than looking into human faces and listening?

      If we are truly an enlightened and caring society, then our response to violence must be to reject resignation and to include actions by those who seek truth and fact. This is now, as ever, our inheritance.

Money, Power, and Choices

[These excerpts are from an article by Maria Fergusob in the November 2018 issue of Phi Delta Kappan.]

      Most years, K-12 education ranks far below topics such as the economy, health care, and immigration among the issues of greatest concern to American voters. In the run-up to the 2018 midterm elections, though, education has taken on a sizable, if not quite leading, role. Across the country, in races big and small, pollsters report high levels of interest in where the candidates stand on teacher pay, student safety, and other school-related topics.

      On the surface, that might suggest a broad resurgence in support for public schooling. But the truth is that public education means very different things to different people. Some voters think of free and open education as a great equalizer, an essential democratic institution that undergirds our very sense of ourselves as a nation. Others think of it solely as a means of promoting their own children’s interests — and they vote accordingly. Not everyone buys into the notion that public schools are meant to be yours, mine, and ours together.

      Indeed, while public school systems, with their tax-based funding and local governing boards, may have been designed to secure the common good, they have changed dramatically over the last half century, becoming less and less equitable and more and more vulnerable to a host of political pressures and moneyed interests. Further, some of the most consequential debates and decisions about public schooling have occurred behind the curtain, outside the view of ordinary Americans. When they vote in local, state, and federal elections, most people — even voters who try to stay well-informed — know little about how campaign donations have influenced the positions their candidates take.

      …wealthy outsiders collaborate to “hijack the democratic process” and unduly influence voting in states and communities where they have no roots, no children, and no ownership. How, they ask, does that kind of outsider influence square with a system that is supposed to be locally controlled?

      It is a fair question. Even if many of these wealthy outsiders have the best of intentions, can we really say that a public system is locally controlled if one point of view is supported by so much external firepower? Unfortunately, the Supreme Court’s 2010 decision in the Citizens United case made this fair question a moot point. Money from all kinds of sources can and does influence elections….

Changing the Game on Climate

[These excerpts are from an interview with Gary Yohe in the 2018 Year in Review issue of The Nature Conservancy.]

      …Climate change poses many risks to nature and human health, and the cost of reducing those risks by reducing carbon emissions will only increase the longer we wait. We’ll get farther in both if, instead of relying on benefit-cost analysis, we accept the recent wisdom of the IPCC that climate change is a risk-management problem. There are real consequences—human lives, extreme weather, ecosystem collapse—that clarify the tradeoffs without undue reliance on monetary analyses.

      …Technology has been changing in favor of renewable energy and will continue to move in that direction. For individuals, speaking to ways that their communities and states can drive clean energy policy and implementation is key. Happily, it’s becoming clear to many corporations that curbing emissions is good for their bottom lines. Many major companies are committing themselves, but everyone needs to follow their lead.

      …Adaptation is essential. We’re not going to “fix” climate change. We’re already seeing its risks, damages and health effects, so supporting adaptation doesn’t mean giving up on mitigation. Both are an essential part of the most efficient portfolio of responses. To help, get educated and figure out what you and your communities can do.

Composites from Renewable and Sustainable Resources: Challenges and Innovations

[This excerpt is from an article by Amar K. Mohanty, Singaravelu Vivekanandhan, Jean-Mathieu Pin and Manjusri Misra in the 2 November 2018 issue of Science.]

      The era of natural fiber composites currently known as biocomposites dates to 1908 with the introduction of cellulose fiber-reinforced phenolic composites. This innovation was followed by synthetic glass fiber-reinforced polyester composites, which obtained commodity status in the 1940s. The use of biobased green polymers to manufacture auto parts began in 1941, when Henry Ford made fenders and deck lids from soy protein-based bioplastic. The use of composite materials, made with newable and sustainable resources, has become one of the vital components of the next generation of industrial practice. Their expanding use is driven by a variety of factors, including the need for sustainable growth, energy security, lower carbon footprint, and effective resource management, while functional properties of the materials are simultaneously being improved. Innovative sustainable resources such as biosourced materials, as well as wastes, coproducts, and recycled materials, can be used as both the matrix and reinforcement in composites to minimize the use of nonrenewable resources and to make better use of waste streams.

      Composite materials find a wide range of potential applications in construction and auto-parts structures, electronic components, civil structures, and biomedical implants. Traditionally, indus-trial sectors that require materials with superior mechanical properties use composites made from glass, aramid, and carbon fibers to reinforce thermoplastics such as polyamide (PA), poly-propylene (PP), and polyvinyl chloride) (PVC), as well as thermoset resins such as unsaturated polyester (UPE) and epoxy resin. In addition to fiber, mineral fillers such as talc, clay, and calcium carbonate are being used in composite manufacturing. Such hybrids of fiber and mineral fillers play a major role in industrial automotive, housing, and even packaging applications. Carbon black plays a vital role as a reinforcement, especially in rubber-based composites. The key environmental concern with regard to composite materials is the difficulty of removing individual components from their structures to enable recycling at the end of a material’s service life. At this point, most composite materials are either sent to a landfill or incinerated. Wood and other natural fibers (e.g., flax, jute, sisal, and cotton), collectively called “biofibers,” can be used to reinforce fossil fuel-based plastic, thus resulting in biocomposite materials. Synthetic glass fiber-reinforced biobased plastics such as polylactides (PLAs) are a type of bio-composite. Biofiber-PP and biofiber-UPE composites have reached commodity status in many auto parts, as well as decking, furniture, and housing applications. Hybrid biocomposites of natural and synthetic fibers as well as mixed matrix systems also represent a key strategy in engineering new classes of biobased composites. As part of feedstock selection, a wide range of renewable products that includes agricultural and forestry residues, wheat straw, rice straw, and waste wood, as well as undervalued industrial coproducts including biofuel coproducts such as lignin, bagasse, and clean municipal solid wastes, is currently being explored to deriVe chemicals and materials. Recent advancements in biorefinery concepts create new opportunities with side-stream product feedstock that can be valorized in the fabrication of a diverse array of biocomposites.

      Materials scientists can help in advancing sustainable alternatives by quantifying the environmental burden of a material through its product life-cycle analysis. The exponential growth of population and modernization of our society will lead to a threefold increase in the demand for global resources if the current resource-intensive path is continued. According to the United Nations, a truckload of plastic waste is poured into the sea every minute. By 2050, at current rates, the amount of plastic in the ocean will exceed the number of fish. The benefit of diverting plastic packaging material is estimated at around $80 billion to $120 billion, which is currently lost to the economy. If diverted for composite use, the recycled and waste plastic currently destined for landfills and incineration would be used for sustainable development, thereby reducing dependence on nonrenewable resources such as petroleum. Postindustrial food processing wastes are being explored as biofiller in biodegradable plastics for the development of compostable biocomposites. Low-value biomass and waste resources can be pyrolyzed to provide biocabon (biochar) as sustainable filler for biocomposite uses. The increased sustainability in composite industries requires basic and transformative research toward the design of entirely green composites. Renewable resourced-based sustainable polymers and bioplastics, as well as advanced green fibers such as lignin-based carbon fiber and nanocellulose, have great potential for sustainable composites. Biobased nonbiodegradable composites show promising applications in auto parts and other manufacturing applications that require durability. Biodegradable composites also show promise in sustainable packaging This comprehensive Review on composites from sustainable and renewable resources aims to summarize their current status, constraints on wider adoption, and future opportunities. In keeping with the broad focus of this article, we analyze the current development of such composites and discuss various fibers and fillers for reinforcements, current trends in polymer matrix systems, and integration of recycled and waste coproducts into composite systems to outline future research trends.

Shifting Summer Rains

[These excerpts are from an article by David McGee in the 2 November 2018 issue of Science.]

      Most of China's water supply depends on rainfall from the East Asian summer monsoon (EASM), a seasonal progression of rains that begins along the southern coast in spring, then sweeps north, reaching northeastern China in midsummer….Projections of the EASM’s response to future climate change are complicated by its complex interaction with the mid-latitude jet stream, which appears to govern the monsoon’s northward march each spring and summer. To investigate the monsoon's sensitivity and dynamics, many scientists have turned to examining its past changes recorded in natural archives. Although past climates are not a direct analog of the 21st-century climate, they offer vital tests of the ability to describe monsoon behavior through theories and numerical models….Through examination of trace elements in Chinese stalagmites (a proxy for local precipitation amount) and climate modeling experiments, they show that cooling episodes in the North Atlantic shifted the summer jet stream south, delaying the onset of monsoon rains in northeastern China and increasing rainfall in central China. The finding demonstrates that local rainfall in the EASM regions can vary in opposition to monsoon strength, and it highlights the importance of future high-latitude warming in determining precipitation patterns in China.

      Central to investigations of the EASM’s history are records of the oxygen isotope composition of rainfall recorded in stalagmites from Chinese caves…

      …The study presents measurements of trace impurities in the calcium carbonate lattice—substitutions of magnesium and strontium for calcium—in two stalagmites from central China that span the transition from the peak of the last ice age to the beginning of the current interglacial period, between 21,000 and 10,000 years ago. These trace-element variations are interpreted to reflect changes in the rate with which infiltrating waters passed through the rock above the cave, which should track local precipitation. Oxygen isotopes in these samples record the same pronounced variations as other Chinese stalagmites during the last deglaciation….

Restoring Lost Grazers Could Help Blunt Climate Change

[These excerpts are from an article by Elizabeth Pennisi in the 26 October 2018 of Science.]

      Restoring reindeer, rhinoceroses, and other large mammals could help protect grasslands, forests, and tundra from catastrophic wildfires and other threats associated with global warming, new studies suggest. The findings give advocates of so-called trophic rewilding—reintroducing lost species to reestablish healthy food webs—a new rationale for bringing back the big grazers….

      Rewilding is often associated with an am-bitious proposal to restore large mammals, including even ice age mammoths, to a huge park in Russia….But mammoth resurrection is still just a dream, and most rewilders are focused on restoring animals including giant tortoises, dam-building beavers, or herds of grazers.

      Now, it seems rewilding could offer a climate bonus. As the planet has warmed, fire seasons have become 25% longer than they were 30 years ago, and more areas are experiencing severe blazes….

      …In the case of white rhinos, fires averaged just 10 hectares when the animals were present—because they kept plants closely cropped, and their paths created fire breaks—but increased to an average of 500 hectares after the rhinos vanished….

      Others are skeptical. Like any ecosystem re-engineering effort, the long-term effects of rewilding are hard to anticipate….Some modeling, for example, suggests increased Arctic grazing will lead to greater carbon release, not less. And creating Arctic herds big enough to make a difference could be difficult….

Like this World of Ours

[This excerpt is from an article by Marcia Bartusiak in the Fall 2018 issue of MIT Spectrum.]

      …But speculation that planetary systems circle other stars started long, long ago—in ancient times. In the fourth century BCE, the Greek philosopher Epicurus, in a letter to his student Herodotus, surmised that there are “infinite worlds both like and unlike this world of ours.” As he believed in an infinite number of atoms careening through the cosmos, it only seemed logical that they’d ultimately construct limitless other worlds.

      The noted 18th-century astronomer William Herschel, too, conjectured that every star might be accompanied by its own band of planets but figured they could “never be perceived by us on account of the faintness of light.” He knew that a planet, visible only by reflected light, would be lost in the glare of its sun when viewed from afar.

      But astronomers eventually realized that a planet might be detected by its gravitational pull on a star, causing the star to systematically wobble like an unbalanced tire as it moves through the galaxy. Starting in 1938, Peter van de Kamp at Swarthmore College spent decades regularly photographing Barnard’s star, a faint red dwarf star located six light-years away that shifts its position in the celestial sky by the width of the Moon every 180 years, faster than any other star. By the 1960s, van de Kamp got worldwide attention when he announced that he did detect a wobble, which seemed to indicate that at least one planet was tagging along in the star’s journey. But by 1973, once Allegheny Observatory astronomer George Gatewood and Heinrich Eichhorn of the University of Florida failed to confirm the Barnard-star finding with their own, more sensitive photographic survey, van de Kamp’s celebrated claim of detecting the first extrasolar planet disappeared from the history books.

      The wobble technique lived on, however, in another fashion. Astronomers began focusing on how a stellar wobble would affect the star’s light. When a star is tugged radially toward the Earth by a planetary companion, the stellar light waves get compressed—that is, made shorter—and thus shifted toward the blue end, of the electromagnetic spectrum. When pulled away by a gravitational tug, the waves are extended and shifted the other way, toward the red end of the spectrum. Over time, these periodic changes in the star’s light can become discernible, revealing how fast the star is moving back and forth due to planetary tugs.

      In 1979, University of British Columbia astronomers Bruce Campbell and Gordon Walker pioneered a way to detect velocity changes as small as a dozen meters a second, sensitive enough for extrasolar planet hunting to begin in earnest. Constantly improving their equipment, planet hunters were even more encouraged in 1983 and 1984 by two momentous events: the Infrared Astronomical Satellite (IRAS) began seeing circumstellar material surrounding several stars in our galaxy; and optical astronomers, taking a special image of the dwarf star Beta Pictoris, revealed an edge-on disk that extends from the star for some 37 billion miles (60 billion kilometers). It was the first striking evidence of planetary systems in the making, suggesting that such systems might be common after all.

      The first indication of an actual planet orbiting another star arrived unexpectedly and within an unusual environment. In 1991, radio astronomers Alex Wolszczan and Dale Frail, while searching for millisecond pulsars at the Arecibo Observatory in Puerto Rico, saw systematic variations in the beeping of pulsar B1257+12, which suggested that three bodies were orbiting the neutron star. Rotating extremely fast, millisecond pulsars are spun up by accreting matter from a stellar companion. So, this system, reported Wolszczan and Frail, “probably consists of 'second generation' planets created at or after the end of the pulsar’s binary history.”

      The principal goal for extrasolar planet hunters, though, was finding evidence for “first generation” planets around stars like our Sun—planets that formed from the stellar nebula itself as a newborn star is created. That long-anticipated event at last occurred in 1994 when Geneva Observatory astrono-mers Michel Mayor and Didier Queloz, working from the Haute-Provence Observatory in southern France, discerned the presence of an object similar to Jupiter orbiting 51 Pegasi, a sunlike star 45 light-years distant in the constellation Pegasus….

Youth Climate Trial Showcases Science

[These excerpts are from an an article by Julia Rosen in the 26 October 2018 issue of Science.]

      Next week, barring a last-minute intervention by the Supreme Court, climate change will go to trial for just the second time in U.S. history. In a federal courtroom in Eugene, Oregon, 21 young people are scheduled to face off against the U.S. government, which they accuse of endangering their future by promoting policies that have increased emissions of carbon dioxide (CO2) and other planet warming gases. The plaintiffs aren’t asking for monetary damages. Instead, they want District Judge Ann Aiken to take the unprecedented step of ordering federal agencies to dramatically reduce the amount of CO2 in the atmosphere.

      Government attorneys are not expected to challenge the scientific consensus that human activities, including the burning of fossil fuels, cause global warming. But the outcome could hinge, in part, on how Aiken weighs other technical issues….

      The civil trial will be a milestone in a hard-fought legal battle that began in 2015, when environmental groups joined with youth activists and retired NASA scientist James Hansen to push for climate action. The lawsuit rests on the novel argument that the government has knowingly violated the plaintiffs’ rights to a “safe” climate by taking actions—such as subsidizing fossil fuels—that cause warming….

      If the trial proceeds, the youths’ lawyers will have to persuade the judge that the government's actions have helped cause climate change; that the warming exacerbated storms, droughts, and wildfires; and that individual plaintiffs have suffered injuries as a result….Hotter, dryer weather increases the risk of fires….And warmer air can hold more moisture, boosting rainfall by up to 20%—a factor he says worsened floods that affected plaintiffs living in Louisiana, Florida, and Colorado….

      The two sides disagree over whether the United States can reduce emissions as fast as the plaintiffs would like. But the government may also argue that any cuts would have a limited impact, because of the global nature of climate change. Other countries now produce roughly 88% of the world’s greenhouse gas emissions….Therefore, the solution requires international cooperation….

      Courts have rejected that argument as a rationale for inaction in previous cases….In the only other climate lawsuit to get to the trial stage—a landmark 2007 case that challenged EPA’s refusal to regulate CO2 from vehicles—the agency claimed doing so wouldn’t matter because U.S. cars contributed just 6% of global emissions. But the Supreme Court disagreed….

Imagine a World without Facts

[These excerpts are from an an editorial by Jeremy Berg in the 26 October 2018 issue of Science.]

      …We are now living in a world where the reality of facts and the importance of scientific inquiry and responsible journalism are questioned with distressing frequency. This trend needs to be called out and arrested; the consequences of allowing it to continue are potentially quite damaging.

      Facts are statements that have a very high probability of being verified whenever appropriate additional observations are made. Thus, facts can be reliably used as key components in interpreting other observations, in making predictions, and in building more complicated arguments….

      Consider the present “post-fact” world in this context. The lack of acceptance and cynical or ignorant questioning of well-documented evidence erode the perception that many propositions are well-supported facts, weakening the foundation on which many discussions and policies rest. Under these circumstances, numerous alternatives appear to be equally plausible because the evidence supporting some of these alternatives has been discounted. This creates a world of ignorance where many possibilities seem equally likely, causing subsequent discussions to proceed without much foundation and with outcomes determined by considerations other than facts.

      Overly discounting information from appropriately trained researchers based on well-conducted studies, or from well-qualified journalists who pursue information with good practices that include interactions with multiple independent sources, can falsely restrict the available evidence. If evidence is judged without regard for its methodological basis, as well as a thorough assessment of sources of bias, unreliable conclusions may be drawn. If shoddy evidence is accepted, false interpretations may appear to be plausible even though they lack substantial evidentiary support. If robust evidence is undervalued or ignored, excess uncertainty will remain even when some propositions should be considered well established.

      To avoid sliding further into a world without facts, we must articulate and defend the processes of evidence generation, evaluation, and integration. This includes not only clear statements of conclusions, but also clear understanding of the underlying evidence with recognition that some propositions have been well established, whereas others are associated with substantial remaining uncertainty. We should acknowledge and accept responsibility for, but not exaggerate, challenges within the scientific enterprise. At the same time, we should continue to call out statements put forward that are factually incorrect with reference to the most pertinent evidence. Without taking these steps forcefully, we risk living in a world where many things do not work as well as we need them to.

Your Genome, on Demand

[These excerpts are from an article by Ali Tozkamani and Eric Topol in the November-December 2018 issue of MIT Technology Review.]

      In early 2018, it was estimated that over 12 million people had had their DNA analyzed by a direct-to-consumer genetic test. A few months later, that number had grown to 17 million. Meanwhile, geneticists and data scientists have been improving our ability to convert genetic data into useful insights—forecasting which people are at triple the average risk for heart attack, or identifying women who are at high risk for breast cancer even if they don't have a family history or a BRCA gene mutation. Parallel advances have dramatically changed the way we search for and make sense of volumes of data, while smartphones continue their unrelenting march toward becoming the de facto portal through which we access data and make informed decisions.

      Taken together, these things will transform the way we acquire and use personal genetic information. Instead of getting tests reactively, on a doctor's orders, people will use the data proactively to help them make decisions about their own health.

      With a few exceptions, the genetic tests used today detect only uncommon forms of disease. The tests identify rare variants in a single gene that causes the disease.

      But most diseases aren’t caused by variants in a single gene. Often a hundred or more changes in genetic letters collectively indicate the risk of common diseases like heart attack, diabetes, or prostate cancer. Tests for these types of changes have recently become possible, and they produce what is known as your “polygenic” risk score. Polygenic risk scores are derived from the combination of these variants, inherited from your mother and father, and can point to a risk not manifest in either parent’s family history. We’ve learned from studies of many polygenic risk scores for different diseases that they provide insights we can’t get from traditional, known risk factors such as smoking or high cholesterol (in the case of heart attack). Your polygenic score doesn’t represent an unavoidable fate—many people who live into their 80s and 90s may harbor the risk for a disease without ever actually getting it. Still, these scores could change how we view certain diseases and help us understand our risk of contracting them.

      Genetic tests for rare forms of disease caused by a single gene typically give a simple yes or no result. Polygenic risk scores, in contrast, are on a spectrum of probability from very low risk to very high risk. Since they’re derived from combinations of genome letter changes that are common in the general population, they’re relevant to everybody. The question is whether we'll find a way to make proper use of the information we get from them….

      Statin drugs are a good case study for this. They’re widely used, even though 95% of the people taking them who haven't had heart disease or stroke get no benefit aside from a nice cholesterol lab test. We can use a polygenic risk score to reduce unnecessary statin use, which not only is expensive but also carries health risks such as diabetes. We know that if you are in the top 20% of polygenic risk for heart attack, you're more than twice as likely to benefit from statins as people in the bottom 20%; these people can also benefit greatly from improving their lifestyle (stop smoking, exercise more, eat more vegetables). So knowing your polygenic risk might cause you to take statins but also make some lifestyle changes….

      And it’s not just about heart disease. A polygenic risk score might tell you that you’re at high risk for breast cancer and spur you to get more intensive screening and avoid certain lifestyle risks. It might tell you that you’re at high risk for colon cancer, and therefore you should avoid eating red meat. It might tell you that you're at high risk for type 2 diabetes, and therefore you should watch your weight….

      Another challenge will be to convince people to forgo or delay medical interventions if they have a low risk of a certain condition. This will require them to agree that they're better off accepting a very low risk of a catastrophic outcome rather than needlessly exposing themselves to a medical treatment that has its own risks….

      You can't change your genetic risk. But you can use lifestyle and medical interventions to offset that risk….

Opening a Door to Eugenics

[These excerpts are from an article by Nathaniel Comfort in the November-December 2018 issue of MIT Technology Review.]

      If this is “the science,” the science is weird. We’re used to thinking of science as incrementally seeking causal explanations for natural phenomena by testing a series of hypotheses. Just as important, good science tries as hard as it can to disprove the working hypotheses.

      Sociogenomics has no experiments, no null hypotheses to accept or reject, no deductions from the data to general principles. Nor is it a historical science, like geology or evolutionary biology, that draws on a long-running record for evidence.

      Sociogenomics is inductive rather than deductive. Data is collected first, without a prior hypothesis, from longitudinal studies like the Framingham Heart Study, twin studies, and other sources of information—such as direct-to-consumer DNA companies like 23andMe that collect biographical and biometric as well, as genetic data on all their clients.

      Algorithms then chew up the data and spit out correlations between the trait of interest and tiny variations in the DNA, called SNPs (for single-nucleotide polymorphisms). Finally, sociogenomicists do the thing most scientists do at the outset: they draw inferences and make predictions, primarily about an individual’s future behavior.

      Sociogenomics is not concerned with causation in the sense that most of us think of it, but with correlation. The DNA data often comes in the form of genome-wide association studies (GWASs), a means of comparing genomes and linking variations of SNPs. Sociogenomics algorithms ask: are there patterns of SNPs that correlate with a trait, be it high intelligence or homosexuality or a love of gambling?

      Yes—almost always. The number of possible combinations of SNPs is so large that finding associations with any given trait is practically inevitable.

      …statistical significance does not equal biological significance. The number of people buying ice cream at the beach is correlated with the number of people who drown or get eaten by sharks at the beach. Sales figures from beachside ice cream stands could indeed be highly predictive of shark attacks. But only a fool would bat that waffle cone from your hand and claim that he had saved you from a Great White….

      Sociogenomics is the latest chapter in a tradition of hereditarian social science dating back more than 150 years. Each iteration has used new advances in science and unique cultural moments to press for a specific social agenda. It has rarely gone well.

      The originator of the statistical approach that sociogenomicists use was Francis Galion, a cousin of Charles Darwin. Galton developed the concept and method of linear regression—fitting the best line through a curve—in a study of human height. Like all the traits he studied, height varies continuously, following a bell-curve distribution. Galton soon turned his attention to personality traits, such as “genius,” “talent,” and “character.” As he did so, he became increasingly hereditarian. It was Galton who gave us the idea of nature versus nurture. In his mind, despite the “sterling value of nurture,” nature was “by far the more important.”

      Galton and his acolytes went on to invent modern biostatistics—all with human improvement in mind….

      …After prominent eugenicists canvassed, lobbied, and testified on their behalf, laws were passed in dozens of states banning “miscegenation” or other “dysgenic” marriage, calling for sexual sterilization of the unfit, and throttling the stream of immigrants from what certain politicians today might refer to as “shithole countries.”

      …Genetics has an abysmal record for solving social problems. In 1905, the French psychologist Simon Binet invented a quantitative measure of intelligence—the IQ test—to identify children who needed extra help in certain areas. Within 20 years, Binet was horrified to discover that people were being sterilized for scoring too low, out of a misguided fear that people of subnormal intelligence were sowing feeblemindedness genes like so much seed corn.

The Cell’s Power Plant

[These excerpts are from an article by Jonathan Shaw in the November-December 2018 issue of Harvard Magazine.]

      Mitochondria produce metabolic energy by oxidizing carbohydrates, protein, and fatty acids. In a five-part respiratory chain, the organelle captures oxygen and combines it with glucose and fatty acids to create the complex organic chemical ATP (adenosine triphosphate), the fuel on which life runs. Cells can also produce a quick and easy form of sugar-based energy without the help of mitochondria, through an anaerobic process called glycolysis, but a mitochondrion oxidizing the same sugar yields 15 times as much energy for the cell to use. This energy advantage is generally accepted as the reason that, between one billion and one and a half billion years ago, a single free-living bacterium and a single-celled organism with a nucleus entered into a mutually beneficial relationship in which the bacterium took up residence inside the cell. No longer free-living, that bacterium evolved to become what is now the mitochondrion, an intracellular organelle.

      Recent discoveries in the Mootha lab have suggested an alternative explanation for this unusual partnership that focuses on the organelle’s ability to detoxify oxygen by consuming it. But whatever the underlying reason, this ancient, extraordinary connection formed just once, Mootha says—and the evolutionary success it conferred was so great that the single cell multiplied and became the ancestor of all plants, animals, and fungi.

      Nobody knows what that first cell looked like, but the bacterium that hitched a ride inside it was probably a relative of the “bugs” that cause Lyme disease, typhus, and chlamydia. In fact, mitochondria are similar enough to these bacteria that when physicians target such intracellular infections with specialized antibiotics, mitochondria are impaired, too….

      The answer lies in evolutionary history. After mitochondria took tki up residence in cells more than a billion years ago—in what was probably a long, drawn-out process—many genes were transferred from the mitochondria into the genome of the host—in other words, into the nucleus of the cell, where most DNA resides. The result of this gene transfer is that the mitochondrial genome, with just 16,000 base pairs (the building blocks of DNA), has been stripped down to bare essentials. Compared to its ancestral form and also to living relatives, such as the Rickettsia bacterium that causes typhus, which has more than a million base pairs, its genome is now tiny.

      …An outpouring of research began to hint at the versatile, indispensable role that mitochondria play in the regulation of cell death, the immune system, and cell signaling. The traditional focus on energy production, in other words, may have misled researchers—all the way back to their interpretation of what happened more than a billion years ago, when that single cell and a lone bacterium entered into a long-term relationship.

      Oxygen levels on early Earth were low at that time, but rising, Mootha says. “We think of oxygen as a life-giving molecule, and it is, but it can also be very corrosive”—think of how it rusts a car. In biology, oxygen and its byproducts are known to cause cellular damage, and are implicated in aging.

      Mitochondria, on the other hand, are consumers of oxygen. Maybe, according to a hypothesis favored by the Mootha lab, the selective advantage that accrued to the first cell to host a mitochondrion was not only more energy, but better control of the toxic effects of oxygen. Normal gene expression supports this idea….

An Alternative Urban Green Carpet

[These excerpts are from an article by Maria Ignatieva and Marcus Hedblom in the 12 October 2018 issue of Science.]

      Lawns are a global phenomenon. They green the urban environment and provide amenable public and private open spaces. In Sweden, 52% of the urban green areas are lawns. In the United States, lawns cover 1.9% of the country’s terrestrial area and lawn grass is the largest irrigated nonfood crop. Assuming lawn would cover 23% of cities globally [on the basis of data from the United States and Sweden], it would occupy 0.15 million to 0.80 million km2 (depending on urban definitions)—that is, an area bigger than England and Spain combined or about 1.4% of the global grassland area. Yet, lawns exact environmental and economic costs, and given the environmental and economic impacts of climate change, it is time to consider new alternative “lawnscapes” in urban planning as beneficial and sustainable alternatives.

      Although lawns are widespread, their properties have received less attention from the scientific community compared to urban trees or any other types of green areas. Designers, urban planners, and politicians tend to highlight the positive ecosystem services provided by lawns. For example, lawns produce oxygen, sequestrate carbon, remove air pollution (although this has not been supported by good quantitative studies), reduce water runoff, increase water infiltration, mit-gate soil erosion, and increase groundwater recharging. But perhaps the most important positive ecosystem service is the aesthetic and recreational benefits they provide. Aesthetics are a primary factor in modern urban planning and landscaping practice. For example, in developing countries located in arid zones, designers argue that lawns and irrigated turfs considerably enhance the quality of urban life.

      Recent heat waves and an increasing prevalence of droughts have raised economic and environmental concerns about the effects of urban lawns on climate change. These circumstances have encouraged researchers and the public to reconsider the green-carpet concept and assess the controversial aspects of lawns. It has been argued that lawns moderate urban temperatures, but this when compared to the absence of any vegetation. In arid regions of the United States, lawn irrigation accounts for 75% of the total annual household water consumption. In Perth, Australia, the annual volume use of groundwater for irrigating public greenspaces is 73 gigaliters (GI) and an additional 72 Gls of water in unlicensed backyard bores for private lawn irrigation. Another concern is the contamination of groundwater or runoff water due to overuse of fertilizers, herbicides, and pesticides. In 2012, the U.S. home and garden sector used 27 million kg of pesticides. The positive effect of soil carbon sequestration on the climate footprint of intensively managed lawns was found to be negated by greenhouse gas emissions from management operations such as mowing, irrigation, and fertilization. Gasoline-powered lawn mowers emitted high amounts of carcinogenic exhaust pollutants. Moreover, substituting degraded open green areas with plastic lawns eliminates real nature from cities and arguably reduces overall sustainability given that they reduce habitats, decrease soil organisms, pollute runoff water, and may well have yet unknown negative consequences for human health through plastic particles.

      However, the most noticeable constraint to new alternative lawn thinking may be the contribution of lawns to urban aesthetic uniformity and urban ecological homogenization, where lawn plant communities become similar across different biophysical settings. From the vast variety of the grass genera, only a limited number of species are selected for lawns….

      The reason behind lawn uniformity may lie in its origin. Grass plots in ornamental gardens most likely appeared in medieval times and were probably obtained from the closest pastures and meadows. They were small and quite biodiverse (containing a large number of meadow herbaceous plants). In the 17th century; the role of lawns increased in the decorative grounds of geometrical gardens. For example, in iconic French Versailles, short-cut green grass was perfectly blended with the ideology of the power of man over nature. The English landscape, or the “natural” style of the 18th century, introduced an idealized version of urban nature: grazed grasslands with scarcely planted shade trees and the “pleasure ground” next to the mansion with a short, smoothly cut lawn. With the introduction of mowers and lawn-seed nurseries, the English pastoral vision flourished further in the public parks during the second half of the 19th century. In the 20th century, the modernistic prefabricated landscape was based on the same English picturesque model as the “natural” landscape, which was often mistaken for ecological quality. Consequently, monoculture and intensively managed lawnscapes dislodged the majority of native zonal plant communities in urban environments. At the beginning of the 21st century, perfect green lawns became part of the uptake by non-Western countries of the ideal Western lifestyle and culture….

      What is the state of alternative lawnscapes today? The most dramatic implementation of new lawn thinking is in Berlin, Germany, where spontaneous vegetation is accepted as a fundamental landscape design tool. In Gleisdreieck Park and Sudgelande Nature Park (both established on abandoned railways), some areas were left to “go wild” and thus have been colonized by spontaneous vegetation. This has successfully challenged societal norms of conventional green lawns and has been accepted by local people. Recent research in the United Kingdom and Sweden showed that people desire to change the monotonous lawn to a more diverse environment. Grass-free lawn is one of the latest movements in both nations and is based on the use of low-growing native (in Sweden) or native and exotic (in the United Kingdom) herbaceous plants without the use of grasses. The goal is to create a dense biodiverse and low-maintenance mat, which can be used for recreation.

      What about future research on urban lawns? Of course, new plant species that can survive heavy tramping or long drought, for example, are desirable. Beyond plant research, studies on planting design must go beyond the theoretical. Specific geographical, cultural, and social conditions of each country must be factored into such alternative lawn planning research. In Australia, South Africa, and Arizona, alternative lawns might be based on xeriscape local plants. In Chinese cities, historically proved groundcover species could provide sustainability and a sense of place. Lawns could become a universal model for experimental sustainable design and urban environment monitoring.

      New alternative lawns represent a new human-made “wild” nature, which is opposed to the “obedient” nature of conventional lawns. Creating a new, ecological norm requires demonstration displays, public education, and the introduction of “compromised” design solutions. For example, a strip of conventional lawn can frame prairie or meadow and other “wild” vegetation and show a presence of culture in nature. The use of colors such as gray, silver, yellow, and even brown in lawnlike covers can add a feeling of real nature. Thus, one crucial challenge is how to accelerate people’s understanding of sustainable alternatives and acceptance of a new vegetation aesthetic in urban planning and design.

The Persistence of Polio

[These excerpts are from a book review by Pamela J. Hines in the 12 October 2018 issue of Science.]

      In the mid-20th century, several successful vaccines against polio were developed, eventually leading to an international initiative in 1988 to eradicate the poliovirus from the planet. After the success of smallpox eradication in 1980, the optimism of the initiative’s advocates and supporters seemed well placed. But some viruses are more unruly than others.

      Is poliovirus eradication an achievable and worthwhile goal or a misapplication of public health efforts…?

      Discovery of polio’s key vaccines was first E, stalled by scientific missteps and later driven by scientists in competition. Many people dedicated their lives to the vaccination programs in hope of eradicating this disease, and others lost theirs to violent resistance against those same campaigns. Evolution and natural selection drove resurgence of new poliovirus strains in regions thought to be cleared. Poverty and remote geography enabled pockets of viral persistence. And the mismatch between where the motivation came from and where the action needed to happen weakened the end game….

      The poliovirus spreads in environments where poor sanitation contaminates water supplies. Children who encounter the virus early in life tend to be less affected, whereas children who are protected from early virus exposure by good water and sanitation systems may be left susceptible to more severe disease when they encounter the virus later on. Thus, better water and sanitation systems may have paradoxically increased the risk of severe disease, offering a potential explanation for why the U.S. polio epidemic seemed to hit children in well-off suburban neighborhoods particularly hard. But regardless of what drove the disease’s spread, the result was a hue and cry to stop the polio outbreaks from countries that had the scientific expertise and money to go after the problem.

      Because of the efforts that ensued, large portions of the world are now free from the constant threat of polio. Not since 1979 has a case of polio originated in the United States, which is stunning progress given that some 58,000 cases of polio originated in the United States in 1952.

      The 1988 initiative to completely eradi-cate polio worldwide, however, has failed to replicate this success….

      With polio cleared from wealthier nations, most of the action now occurs in developing areas, where public health systems must deal with a variety of pressing challenges, of which polio is only one. The virus persists in impoverished regions, where inadequate water and sanitation systems facilitate its spread. Weak health care systems struggle to sustain even minimal programs against scourges of childhood, ranging from measles to malnutrition.

      The vaccines do work. But controlling the poliovirus has proven to be more dif-ficult than expected.

A New Leaf

[These excerpts are from an article by Erik Stokstad in the 12 October 2018 issue of Science.]

      Mikael Fremont was up to his shoulders in rapeseed…to point out something nearly hidden: a mat of tattered, dead leaves covering the soil.

      Months earlier, Fremont had planted this vetch and clover along with the rapeseed. The two legumes had grown rapidly, preventing weeds from crowding out the emerging rapeseed and guarding it from hungry beetles and weevils. As a result, Fremont had cut by half the herbicide and insecticide he sprayed. The technique of mixing plant species in a single field had worked “perfectly,” he said.

      This innovative approach is just one of many practices, now spreading across France, that could help farmers achieve an elusive national goal. In 2008, the French government announced a dramatic shift in agricultural policy, calling for pesticide use to be slashed in half. And it wanted to hit that target in just a decade. No other country with as large and diverse an agricultural system had tried anything so ambitious….

      Since then, the French government has spent nearly half a billion euros on implementing the plan, called Ecophyto. It created a network of thousands of farms that test methods of reducing chemical use, improved national surveillance of pests and plant diseases, and funded research on technologies and techniques that reduce pesticide use. It has imposed taxes on farm chemicals in a bid to decrease sales, and even banned numerous pesticides, infuriating many farmers.

      The effort has helped quench demand on some farms. Overall, however, Ecophyto has failed miserably. Instead of declining, national pesti-cide use has increased by 12%, largely mirroring a rise in farm production….

      There is also optimism. Despite Ecophyto’s failure, it showed farmers have powerful options, such as mixing crops, planting new varieties, and tapping data analysis systems that help identify the best times to spray. With the right incentives and support, those tools might make a bigger difference this time around. And the fact that France isn't backing away from its ambitious goal inspires many observers….

      It’s not only farmers who will have to adjust if France is to meet its ambitious goals. Reducing the cost of food production to the environment and public health will likely increase the cost to consumers and taxpayers….

Teaching Tolerance

[These excerpts are from an article by Josh Grossberg is in the Autumn 2018 issue of USC Trojan Family.]

      The 2018 Winter Olympics were in full swing and the students in Ivy Schamis’ high school classroom were upbeat. The teacher was guiding the students in her Holocaust history class through a discussion about the 1936 Summer Olympics. – She described how a German man had given famed black track athlete Jesse Owens a pair of specially designed running shoes despite risk of repercussions from the Nazi government. – “Does anybody know who that man was?” Schamis asked. A young man raised his hand. For the first time Schamis could remember, a student knew the answer. The shoemaker was Adi Dassler, the founder of Adidas, 17-year-old Nicholas Dworet said proudly.

      That’s when the shooting started.

      Gunfire rang out, one bullet after another. Someone was firing into the classroom. “We just flew out of our seats and tried to take cover,” Schamis says, “but there was nowhere to hide.”

      Two minutes later, Dworet and another student, named Helena Ramsay, also 17, were killed by gunfire. They were among the 17 students slain on Feb. 14, 2018, in the tragic shooting at Marjory Stoneman Douglas High School in Parkland, Florida….

      It may seem ironic that a classroom dedicated to embracing cross-cultural understanding would be visited upon by such senseless violence. But it was that kind of violence that prompted Schamis to delve into the topic with her students in the first place.

      “The lessons of the Holocaust came right into Room 1214 that day,” Schamis says….

      Can education truly instill decency and respect, and do the actions of individuals matter in fighting hate? Vigorous evaluations and studies conducted by the institute provide reason for hope. USC Shoah Foundation research has shown that 78 percent of students recognized that one person can make a difference if they see an example of stereotyping against a group of people. Another 78 percent believe it’s important to speak up against stereotyping when they see it around them.

      “If we have racist and anti-Semitic ideologies coming at us, then we can develop in students the skills, knowledge, abilities and capacities to counter those ideologies, make better decisions and be more active in opposing those ideologies as dtizens,”Wiedeman says.

      Wiedeman and USC Shoah Foundation aren’t alone in be-lieving that empathy, openness and tolerance can be taught….

      Florida high school teacher Ivy Schamis says that despite the shooting in her classroom, she remains undaunted in her quest to spread a belief in shared human values. She’s more eager than ever to teach students the lessons of the Holocaust.

      “Hate is never OK. Tell everybody,” she says. “We have to be there for each other.”

The Good Fight

[These excerpts are from a letter to the editor by Michael P. Jansen is in the October 2018 issue of Chem 13 News.]

      …when people discover I’m a teacher (a chemistry teacher! AHHH!!!), it’s pretty much game over….

      I cannot take peoples' illusion that chemistry is memorization. Or that school is about getting good marks — so a student can get accepted to some university…in order to — you guessed it — get more good marks — so he can be a doctor (like his aunt in England).

      I hate that parents have their kids take a summer course “to get it out of the way”. I hate that students and parents and (I am sorry to say) many teachers and some “experts” believe that computers are the Holy Grail in this business.

      Let’s get real. School is — and always was and always will be — about learning. I don’t understand why this straight-forward message is so difficult. We need to promote learning, while de-emphasizing marks. This is a war. We need to fight — student by student, class by class, year over year, parent interview by parent interview. It won’t be easy; there will be casualties, like my sanity — or your sanity.

      Let’s stand together and fight the good fight. For chemistry education. For chemistry learning.

Japan Needs Gender Equality

[These excerpts are from an editorial by Yumiko Murakami and Francesca Borgonovi is in the 12 October 2018 issue of Science.]

      Last month, Tokyo Medical University (TMU) announced Yukiko Hayashi as its first female president. This comes on the heels of discovering that the insitution had manipulated entrance exam scores for many years to curb female enrollment. Hayashi may be an attempt by TMU to restore its reputation, but the scandal should be a wake-up call for Japanese society to ensure that men and women have equal opportunities to succeed….

      Yet, Japan boasts one of the most sophisticated educational systems in the world. Japanese 15-year-old students are among the highest performers in mathematics and science according to the OECD’s Programme for International Student Assessment (PISA). However, a gender gap is noticeable, especially among top-tier students. The latest PISA assessment in 2015 indicates that Japanese boys outperform girls in mathematics by ~15% of a standard deviation on the achievement scale. Among the top 10% of students in Japan, there is an even larger gender gap in both mathematics and science. But by international standards, Japanese girls perform at very high levels. For example, the highest-achieving girls in Japan performed significantly above the highest-achieving boys from most of the other 70 education systems assessed by PISA in both mathematics and science….

      Fostering confidence in female students, trainees, and professionals would be a highly effective way to close the gender gap in Japan. Gender mainstreaming in various segments of Japanese society is crucial to address unconscious biases. A better gender balance in professional occupations, especially in STEM fields, would boost self-efficacy in female students, and TMU’s decision to appoint a female president is a major step toward promoting more female role models in medicine. Medical schools should work with hospitals to improve working conditions so that female physicians are not hampered in their careers by life events such as pregnancies and child-rearing.

      Halving Japan’s gender gap in the labor force by 2025 could add almost 4 percentage points to projected growth in gross domestic product over the period from 2013 to 2025. Japan clearly needs to embrace women to bolster its economy. And having more highly educated women in medical professions is particularly beneficial for a country with a rapidly aging population. Gender equality will be the key for better lives for all Japanese.

Father of ‘the God Particle’ Dies

[This brief news article is in the 12 October 2018 issue of Science.]

      Leon Lederman, a Nobel Prize-winning physicist and passionate advocate for science education, died last week at age 96. He and two colleagues shared the physics Nobel in 1988 for their discovery 26 years earlier that elusive particles called neutrinos come in more than one type. Lederman became identified with the neologism in the title of his 1993 book, The God Particle: If the Universe Is the Answer, What Is the Question? He was referring to the Higgs boson, the last missing piece of physicists’ standard model of fundamental particles and forces, which was finally discovered in 2012. Some physicists scorned the title. Lederman puckishly claimed his publisher balked at Goddamn Particle, which would have conveyed how hard physicists were struggling to detect the Higgs.

Mythical Androids and Ancient Automatons

[These excerpts are from a book review by Sarah Olson in the 5 October 2018 issue of Science.]

      Long before the advent of modern robots and artificial intelligence (AI), automated technology existed in the storytelling and imaginations of ancient societies. Hephaestus, blacksmith of the mythical Greek gods, fashioned mechanical serving maids from gold and endowed them with learning, reason, and skill in Homer’s Iliad. Designed to anticipate their master’s requests and act on them without instruction, the Golden Maidens share similarities with modern machine learning, which allows AI to learn from experience without being explicitly programmed.

      The possibility of AI servants continues to tantalize the modern imagination, resulting in household automatons such as the Roomba robot vacuum and Amazon’s virtual assistant, Alexa. One could imagine a future iteration of Alexa as a fully automatic robot, perhaps washing our dishes or reminding us to pick up the kids after school. In her new book, Gods and Robots, Adrienne Mayor draws comparisons between mythical androids and ancient robots and the AI of today….

      Through detailed storytelling and careful analysis of popular myths, Mayor urges readers to consider lessons learned from these stories as we set about creating a new world with AI. Like Pandora, an automaton created by Hephaestus who opened a box and released evils into the world, AI could bring about unforeseen problems. Here, Mayor cites Microsoft’s 2016 experiment with the Twitter chatbot “Tay,” a neural network programmed to converse with Twitter users without requiring supervision. Only hours after going live, Tay succumbed to a group of followers who conspired to turn the chatbot into an internet troll. Microsoft’s iteration the following year suffered a similar fate.

      Despite her extensive knowledge of ancient mythology Mayor does little to demonstrate an understanding of modern Al, neural networks, and machine learning; the chatbots are among only a handful of examples of modern technology she explores.

      Instead, Mayor focuses on her own area of expertise: analyzing classical mythology. She recounts, for example, the story of the bronze robot Talos, an animated statue tasked with defending the Greek island of Crete from pirates….

      When Pandora opens her box of evils, she releases hope by accident—inadvertently helping humanity learn to live in a world now corrupted by evil. Like this story Gods and Robots is cautionary but optimistic. While warning of the risks that accompany the irresponsible deployment of technology Mayor reassures readers that AI could indeed bring about many of the wonderful things that our ancestors imagined.

Junk Food, Junk Science?

[This excerpt is from a book review by Cyan James in the 5 October 2018 issue of Science.]

      …In her latest book, Unsavory Truth, [Marion] Nestle levels a withering fusillade of criticism against food and beverage companies that use questionable science and marketing to push their own agendas about what should end up on our dinner tables.

      In her comprehensive review of companies’ nutrition research practices, Nestle (whose name is pronounced “Nes-sul” and who is not affiliated with the Swiss food company) reveals a passion for all things food, combined with pronounced disdain for the systematic way food companies influence the scientists and research behind the contents of our pantries. Her book is an autopsy of modern food science and advertising, pulling the sheet back on scores of suspect practices, as well as a chronicle of Nestle’s own brushes with food company courtship.

      Is it shocking that many food companies do whatever they can in the name of fatter profits? Maybe, but it's old hat for Nestle, who has spent five decades honing her expertise and is a leading scholar in the field of nutrition science. In this book, she details nearly every questionable food company tactic in the playbook, from companies that fund their own food science research centers and funnel media attention to nondietary explanations for obesity, to those that cherry-pick data or fund professional conferences as a plea for tacit approval.

      Even companies that hawk “benign” foods such as blueberries, pomegranate juice, and nuts come under the author’s strict scrutiny because, as she reminds readers, “Foods are not drugs. To ask whether one single food has special health benefits defies common sense.”

      Instead, Nestle urges eaters to look behind the claims to discover who funds food-science studies, influences governmental regulations, advises policy-makers, and potentially compromises researchers. Food fads, we learn, can spring from a few findings lifted out of context or interpreted with willful optimism. Companies, after all, can hold different standards for conducting and interpreting research than those of independent academic institutions or scientific organizations and can be driven by much different motives.

      Nestle wields a particularly sharp pen against junk-food purveyors, soda companies, and others who work hard to portray excess sugar as innocuous or who downplay the adverse effects their products can have. These companies adopt tactics such as founding research centers favorable to their bottom line, diverting consumer attention away from diet to focus instead on the role of exercise in health, or trying to win over individual researchers to favorably represent their products. Nestle calls foul on these attempts to portray junk foods as relatively harmless, even knocking the “health halo” shine from dark chocolates and other candies masquerading as responsible health foods.

      Not content to point to the many thorny problems lurking behind food company labels and glitzy sponsored meetings, however, Nestle offers a constructive set of suggestions for how nutrition scientists can navigate potential conflicts of interest.

      Consumers, too, bear a responsibility for promoting eating habits that steer clear of dubious advertising. Nestle advocates adhering to a few simple guidelines: “[E]at your veggies, choose relatively unprocessed foods, keep junk foods to a minimum, and watch out for excessive calories!” We have the power of our votes and our forks, she reminds us, and can use both to insist that food compa-nies help us eat well. Nestle’s determination to go to bat for public health shines through, illuminating even her occasional sections of workaday prose or dense details.

      Nestle marshals a convincing number of observations on modern food research practices while energetically delineating how food companies’ clout can threaten the integrity of the research performed on their products. There is indeed something rotten in the state of dietary science, but books like this show us that we consumers also hold a great deal of power.

Renewable Energy for Puerto Rico

[These excerpts are from an editorial by Arturo Massol-Deya, Jennie C. Stephens and Jorge L. Colon in the 5 October 2018 issue of Science.]

      Puerto Rico is not prepared for another hurricane. A year ago, Hurricane Maria obliterated the island’s electric grid, leading to the longest power outage in U.S. history. This disrupted medical care for thousands and contributed to an estimated 2975 deaths. The hurricane caused over $90 billion in damage for an island already in economic crisis. Although authorities claim that power was restored completely, some residents still lack electricity. Despite recovery efforts, the continued vulnerability of the energy infrastructure threatens Puerto Rico’s future. But disruptions create possibilities for change. Hurricane Maria brought an opportunity to move away from a fossil fuel-dominant system and establish instead a decentralized system that generates energy with clean and renewable sources. This is the path that will bring resilience to Puerto Rico.

      Puerto Rico is representative of the Caribbean islands that rely heavily on fossil fuels for electric power; 98% of its electricity comes from imported fossil fuels (oil, natural gas, and coal), whereas only 2% comes from renewable sources (solar, wind, or hydroelectric)….This makes the island's centralized electrical grid vulnerable to hurricanes that are predicted to increase in severity because of climate change.

      In Puerto Rico and the rest of the Caribbean, where sun, wind, water, and biomass are abundant sources of renewable energy, there is no need to rely on fossil fuel technology. Unfortunately, the government of Puerto Rico and the U.S. Federal Emergency Management Agency have been making decisions about the local power authority that are restoring the energy system to what it was before Hurricane Maria hit, perpetuating fossil fuel reliance….

      At this juncture, when the opportunity to build a sustainable and resilient electrical system presents itself, moving away from dependency on imported fossil fuels should be the guiding vision. Puerto Rico must embrace the renewable endogenous sources that abound on the island and build robust microgrids powered by solar and wind, install hybrid systems (such as biomass biodigesters), and create intelligent networks that can increase the resilience of the island. The Puerto Rican government and U.S. Congress should use Hurricane Maria as a turning point for pushing Puerto Rico toward using 100% renewable energy rather than a platform to plant generators across the island….

Boys Will Be Superintendents: School Leadership as a Gendered Profession

[These excerpts are from an article by Robert Maranto, Kristen Carroll, Albert Cheng and Manuel P. Teodoro in the October 2018 issue of Phi Delta Kappan.]

      In 19th-century America, both teaching and school leadership were mainly feminine pursuits, in part because most people considered women better at nurturing children, but also because local school boards could get away with paying women less. Eventually, however, progressives sought to professionalize educational leadership with larger, bureaucratic schools led by credentialed principals and su perintendents….At a time when professional meant male, this bureaucratization and professionalization of schools meant replacing female principals and superintendents with men.

      As Kate Rousmaniere…details in her social history of the principalship, graduate programs providing educational leadership credentials served as an increasingly common career pathway for men, particularly veterans who returned from World War II and attended graduate school on the GI Bill. In addition, the emerging field of athletic coaching not only attracted many men to jobs in education but also gave them dear routes to principal and superintendent posts….

      Thus, by the 1970s, researchers found that nearly 80 percent of school superintendents had coached athletic teams earlier in their careers….

      As a result, explains Rousmaniere, the numbers of women in school and district leadership declined through most of the 20th century. For example, the percentage of elementary school principal posts held by women fell from 55% in 1928 to 20% in 1973. Since high school enrollments were rare in the early part of the century, and secondary leadership positions were already seen as relatively prestigious, the number of women in high school leadership was always low, even in the 1920s, but by mid-century it fell to just 1%. By the 1960s, Rousmaniere notes, “It seemed to be the natural order of things that women taught and men managed….”

      Today, the outlook for women in leadership is significantly better, but there's still a serious imbalance. For example, using data on more than 7,500 public school principals from the U.S. Department of Education 2011-12 Schools and Staffing Survey and additional published sources, we recently found that while 90% of elementary teachers are women, only 66% of elementary principals are women. In secondary schools, meanwhile, women make up 63% of teachers but just 48% of principals.

      Before becoming principals, men and women are about equally likely to have served as department heads, vice principals, and dub advisers. In two key respects, however, their paths to the principalship differ. Women are twice as likely as men to have prior service as curricular specialists (31.3% of women and 16010 of men), and men are three times as likely (52.8% of men and 16.5% of women) to have had prior experience as athletic coaches….Overall, men are proportionately more likely to gain promotion to principal, and to do so more quickly than women. In traditional public schools, male principals have taught a mean of only 10.7 years before becoming principal compared to 13.2 years for women.

      The imbalance continues beyond the principalship, too. Nationwide, for example, just 24.1% of superintendents are women….

True Story

[These excerpts are from an article by Steve Mirsky in the October 2018 issue of Scientific American.]

      …The Washington Post tallied 4,229 “false or misleading claims” by Trump in his first 558 days in office…

      Here’s an example of my conundrum. Early this year, Trump refuted the idea of climate change: “The ice caps were going to melt, they were going to be gone by now but now they’re setting records, so okay, they’re at a record level.” But a researcher at the National Snow and Ice Data Center said that polar ice was at “a record low in the Arctic (around the North Pole) right now and near record low in the Antarctic (around the South Pole).” The Trump claim and the response were both published by the Pulitzer Prize-winning organization PolitiFact….

      I was reading a book. The book is called The Death of Truth. The writer’s name is Michiko Kakutani. She wrote that the Trump administration ordered the Centers for Disease Control and Prevention to avoid using the terms “science-based” and “evidence-based.” She says that in another book called 1984 there’s a society that does not even have the word “science” because, as she quoted from that other book, “‘the empirical method of thought, on which all the scientific achievements of the past were founded,’ represents an objective reality that threatens the power of Big Brother to determine what truth is.”…

      Maria Konnikova is a science journalist. She also has a doc-torate in psychology….She wrote an article for a place called Politico entitled “Trump's Lies vs. Your Brain.” She wrote, “If he has a particular untruth he wants to propagate ... he simply states it, over and over. As it turns out, sheer repetition of the same lie can eventually mark it as true in our heads.” She also wrote that because of how our brains work, “Repetition of any kind—even to refute the statement in question—only serves to solidify it.”

Clicks, Lies and Videotapes

[These excerpts are from an article by Brooke Borel in the October 2018 issue of Scientific American.]

      The consequences for public knowledge and discourse could be profound. Imagine, for instance, the impact on the upcoming midterm elections if a fake video smeared a politician during a tight race. Or attacked a CEO the night before a public offering. A group could stage a terrorist attack and fool news outlets into covering it, sparking knee-jerk retribution. Even if a viral video is later proved to be fake, will the public still believe it was true anyway? And perhaps most troubling: What if the very idea of pervasive fakes makes us stop believing much of what we see and hear—including the stuff that is real?

      …The path to fake traces back to the 1960s, when computer-generated imagery was first conceived. In the 1980s these special effects went mainstream, and ever since, movie lovers have watched the technology evolve from science-fiction flicks to Forrest Gump shaking hands with John F. Kennedy in 1994 to the revival of Peter Cushing and Carrie Fisher in Rogue One….

      Experts have long worried that computer-enabled editing would ruin reality. Back in 2000, an article in MIT Technology Review about products such as Video Rewrite warned that “seeing is no longer believing” and that an image “on the evening news could well be a fake—a fabrication of fast new video-manipulation technology.” Eighteen years later fake videos don't seem to be flooding news shows. For one thing, it is still hard to produce a really good one….

      The way we consume information, however, has changed. Today only about half of American adults watch the news on television, whereas two thirds get at least some news via social media, according to the Pew Research Center. The Internet has allowed for a, proliferation of media outlets that cater to niche audiences—including hyperpartisan Web sites that intentionally stoke anger, unimpeded by traditional journalistic standards. The Internet rewards viral content that we are able to share faster than ever before….And the glitches in fake video are less dis-cernible on a tiny mobile screen than a living-room TV.

      The question now is what will happen if a deepfake with significant social or political implications goes viral. With such a new barely studied frontier, the short answer is that we do not know….

      The science on written fake news is limited. But some research suggests that seeing false information just once is sufficient to make it seem plausible later on….

End of the Megafauna

[These excerpts are from a brief article in the Fall 2018 issue of Rotunda, put out by the American Museum of Natural History.]

      The American Museum of Natural History is world famous for its vertebrate paleontology halls, where the story of vertebrate life is traced from its beginnings to the near present, as told by the most direct form of evidence we have: the fossils themselves….

      At one end of the wing are a Columbian mammoth and an American mastodon. Both are very definitely proboscidean, or elephantlike, in body form, although their last common ancestor lived about 25 million years ago. On the North American mainland, populations of mammoths and mastodons were still living as recently as 12,000 years ago; all were gone 1,000 or so years later. A couple of island-bound groups of woolly mammoths struggled on, but these too had disappeared by 4,200 years ago. Asian and African elephants persisted. These magnificent beasts didn’t. Why?

      Elsewhere in the hall are members of Xenarthra, today an almost exclusively South American group that includes living armadillos, tree sloths, and anteaters. The largest of the living xenarthrans is the giant anteater (MyrInecophaga tridactyla), but as late as 12,000 to 13,000 years ago there were several much larger xenarthran species in both North and South America that ao may have weighed as much as 2,000-4,000 kg. Among these was gigantic Lestodo, whose closest living relatives, the two-and three-toed tree sloths Choloepus and Bradypus, weigh no more than 5 kg. They made it, Lestodon didn’t. Why?

      Many other Quaternary species prospered in their native environments for hundreds of thousands of years or more without ro suffering any imperiling losses. But beginning about 50,000 years ago, something started happening to large animals. Species sometimes disappeared singly, at other times in droves. Size must have mattered, because their smaller close relatives mostly weathered the extinction storm and are still with us.

      So why did these megafaunal extinctions occur?

      A short but honest reply would be that there is no satisfactory answer-not yet. The debate continues as fresh leads are traced and dead ends abandoned or refashioned in order to accommodate new evidence. It's a great time to be a Quaternary paleontologist!

The Marvelous Mola

[These excerpts are from a brief article in the Fall 2018 issue of Rotunda, put out by the American Museum of Natural History.]

      Mola may not be a household name, but the various species of this genus of sunfish are found in temperate and tropical seas all over the world and can reach nearly 11 feet (3.5 meters) in length and weigh up to 5,070 lbs (2,300 kg).

      To live large, these marine giants grow fast: in captivity, young sunfish can pack on more than 800 pounds in just over a year….

      Size gives the Mola mola several advantages. Females produce enormous numbers of eggs: one 4-foot (1.2 meter-long) female was estimated to be carrying 300 million eggs. The Mola mola also has a broad thermal range, from 36°F to 86°F, allowing it to dive more than 3,000 feet deep (914 meters). There is slim preliminary evidence that the ocean sunfish may he able to tolerate low oxygen levels, but that would be a boon, as such conditions are among a growing list of concerns in today’s oceans, along with human pollution and global sea temperature rise.

      As adults, their appetite for jellyfish means ocean sunfish are helping combat another modern marine threat. “As we overfish the ocean, in some regions, jellies can move in to fill those open niches,” says marine biologist Tierney Thys, who has tracked ocean sunfishes all over the globe. “As these local jelly populations increase, we need to keep our populations of jelly eaters–like the Mola mola–intact.”

Abortion Facts

[These excerpts are from an article by Michael Shermer in the September 2018 issue of Scientific American.]

      In May of this year the pro-life/pro-choice controversy leapt back into headlines when Ireland overwhelmingly approved a referendum to end its constitutional ban on abortion. Around the same time, the Trump administration proposed that Title X federal funding be withheld from abortion clinics as a tactic to reduce the practice, a strategy similar to that of Texas and other states to shut down clinics by burying them in an avalanche of regulations, which the U.S. Supreme Court struck down in 2016 as an undue burden on women for a constitutionally guaranteed right. If the goal is to attenuate abortions, a better strategy is to reduce unwanted pregnancies. Two methods have been proposed: abstinence and birth control. /p>

      Abstinence would obviate abortions just as starvation would forestall obesity. There is a reason no one has proposed chastity as a solution to overpopulation. Sexual asceticism doesn’t work, because physical desire is nearly as fundamental as food to our survival and flourishing. A 2008 study…found that among American adolescents ages 15 to 19, “abstinence-only education did not reduce the likelihood of engaging in vaginal intercourse" and that "adolescents who received comprehensive sex education had a lower risk of pregnancy than adolescents who received abstinence-only or no sex education.”

      …When women are educated and have access to birth-control technologies, pregnancies and, eventually, abortions decrease. A 2003 study…concluded that abortion rates declined as contraceptive use increased in seven countries (Kazakhstan, Kyrgyzstan, Uzbekistan, Bulgaria, Turkey, Tunisia and Switzerland). In six other nations (Cuba, Denmark, the Netherlands, Singapore, South Korea and the US.), contraceptive use and abortion rates rose simultaneously, but overall levels of fertility were falling during the period studied. After fertility levels stabilized, contraceptive use continued to increase, and abortion rates fell.

      Something similar happened in Turkey between 1988 and 1998, when abortion rates declined by almost half when unreli-able forms of birth control (for one, the rhythm method) were replaced by more modern technologies (for example, condoms)….

      To be fair, the multivariable mesh of correlations in all 1 these studies makes inferring direct causal links difficult for social scientists to untangle. But as I read the research, when women have limited sex education and no access to contraception, they are more likely to get pregnant, which leads to higher abortion rates. When women are educated about and have access to effective contraception, as well as legal and medically safe abortions, they initially use both strategies to control family size, after which contraception alone is often all that is needed and abortion rates decline. Admittedly, deeply divisive moral issues are involved. Abortion does end a human life, so it should not be done without grave consideration for what is at stake, as we do with capital punishment and war. Likewise, the recognition of equal rights, especially reproductive rights, should be acknowledged by all liberty-loving people. But perhaps progress for all human life could be more readily realized if we were to treat abortion as a problem to be solved rather than a moral issue over which to condemn others. As gratifying as the emotion of moral outrage is, it does little to bend the moral arc toward justice.

Alone in the Milky Way

[This excerpt is from an article by John Gribbin in the September 2018 issue of Scientifi American.]

      DNA evidence pinpoints two evolutionary bottle-necks in particular. A little more than 150,000 years ago the human population was reduced to no more than a few thousand—perhaps only a few hundred—breeding pairs. And about 70,000 years ago the entire human population fell to about 1,000. Although this interpretation of the evidence has been questioned by some researchers, if it is correct, all the billions of people now on Earth are descended from this group, which was so small that a species diminished to such numbers today would likely be regarded as endangered.

      That our species survived—and even flourished, eventually growing to number more than seven billion and advancing into a technological society—is amazing. This outcome seems far from assured.

      As we put everything together, what can we say? Is life likely to exist elsewhere in the galaxy? Almost certainly yes, given the speed with which it appeared on Earth. Is another technological civilization likely to exist today? Almost certainly no, given the chain of circumstances that led to our existence. These considerations suggest we are unique not just on our planet but in the whole Milky Way. And if our planet is so special, it becomes all the more important to pre-serve this unique world for ourselves, our descendants and the many creatures that call Earth home.

Why We Fight

[These excerpts are from an article by R. Brian Ferguson in the September 2018 issue of Scientifi American.]

      Do people, or perhaps just males, have an evolved predisposition to kill members of other groups? Not just a capacity to kill but an innate propensity to take up arms, tilting us toward collective violence? The word “collective” is key. People fight and kill for personal reasons, but homicide is not war. War is social, with groups organized to kill people from other groups. Today controversy over the historical roots of warfare revolves around two polar positions. In one, war is an evolved propensity to eliminate any potential competitors. In this scenario, humans all the way back to our common ancestors with chimpanzees have always made war. The other position holds that armed conflict has only emerged over recent millennia, as changing social conditions provided the motivation and organization to collectively kill. The two sides separate into what the late anthropologist Keith Otterbein called hawks and doves….

      If war expresses an inborn tendency, then we should expect to find evidence of war in small-scale societies throughout the prehistoric record. The hawks claim that we have indeed found such evidence….

      …If wars are natural eruptions of instinctive hate, why look for other answers? If human nature leans toward collective killing of outsiders, how long can we avoid it?

      The anthropologists and archaeologists in the dove camp challenge this view. Humans, they argue, have an obvious capacity to engage in warfare, but their brains are not hardwired to identify and kill outsiders involved in collective conflicts. Lethal group attacks, according to these arguments, emerged only when hunter-gatherer societies grew in size and complexity and later with the birth of agriculture. Archaeology, supplemented by observations of contemporary hunter-gatherer cultures, allows us to identify the times and, to some degree, the social circumstances that led to the origins and inten-sification of warfare.

      In the search for the origins of war, archaeologists look for four kinds of evidence. The artwork on cave walls is exhibit one. Paleolithic cave paintings from Grottes de Cougnac, Pech Merle and Cosquer in France dating back approximately 25,000 years show what some scholars perceive to be spears penetrating people, suggesting that people were waging war as early as the late Paleolithic period. But this interpretation is contested. Other scientists point out that some of the incomplete figures in those cave paintings have tails, and they argue that the bent or wavy lines that intersect with them more likely represent forces of shamanic power, not spears. (In contrast, wall paintings on the eastern Iberian Peninsula, probably made by settled agriculturalists thousands of years later, clearly show battles and executions.)

      Weapons are also evidence of war, but these artifacts may not be what they seem…

      Beyond art and weapons, archaeologists look to settlement remains for clues. People who fear attack usually take precautions….

      Skeletal remains would seem ideal for determining when war began, but even these require careful assessment. Only one of three or four projectile wounds leaves a mark on bone. Shaped points made of stone or bone buried with a corpse are sometimes ceremonial, sometimes the cause of death. Unhealed wounds to a single buried corpse could be the result of an accident, an execution or a homicide. Indeed, homicide may have been fairly common in the prehistoric world—but homicide is not war. And not all fights were lethal….

      The global archaeological evidence, then, is often ambiguous and difficult to interpret. Often different clues must be pieced together to produce a suspicion or probability of war….

      The preconditions that make war more likely include a shift to a more sedentary existence, a growing regional population, a concentration of valuable resources such as livestock, increasing social complexity and hierarchy, trade in high-value goods, and the establishment of group boundaries and collective identities. These conditions are sometimes combined with severe environmental changes….

      The preconditions for war are only part of the story, however, and by themselves, they may not suffice to predict outbreaks of collective conflicts. In the Southern Levant, for instance, those preconditions existed for thousands of years without evidence of war….

      People are people. They fight and sometimes kill. Humans have always had a capacity to make war, if conditions and culture so dictate. But those conditions and the warlike cultures they generate became common only over the past 10,000 years—and, in most places, much more recently than that. The high level of killing often reported in history, ethnography or later archaeology is contradicted in the earliest archaeological findings around the globe. The most ancient bones and artifacts are consistent with the ti-tle of Margaret Mead’s 1940 article: “Warfare Is Only an Invention—Not a Biological Necessity.”

Last Hominin Standing

[This excerpt is from an article by Kate Wong in the September 2018 issue of Scientifi American.]

      …It now looks as though H. sapiens originated far earlier than previously thought, possibly in locations across Africa instead of a single region, and that some of its distinguishing traits—including aspects of the brain—evolved piecemeal. Moreover, it has become abundantly clear that H. sapiens actually did mingle with the other human species it encountered and that interbreeding with them may have been a crucial factor in our success. Together these findings paint a far more complex picture of our origins than many researchers had envisioned—one that privileges the role of dumb luck over destiny in the success of our kind.

      Debate about the origin of our species has traditionally focused on two competing models. On one side was the Recent African Origin hypothesis…which argues that H. sapiens arose in either eastern or southern Africa within the past 200,000 years and, because of its inherent superiority, subsequently replaced archaic hominin species around the globe without interbreeding with them to any significant degree. On the other was the Multiregional Evolution model…which holds that modem H. sapiens evolved from Neandertals and other archaic human populations throughout the Old World, which were connected through migration and mating. In this view, H. sapiens has far deeper roots, reaching back nearly two million years.

      By the early 2000s the Recent African Origin model had a wealth of evidence in its favor. Analyses of the DNA of living people indicated that our species originated no more than 200,000 years ago. The earliest known fossils attributed to our species came from two sites in Ethiopia, Omo and Herto, dated to around 195,000 and 160,000 years ago, respectively. And sequences of mitochondrial DNA (the tiny loop of genetic material found in the cell’s power plants, which is different from the DNA contained in the cell’s nucleus) recovered from Neandertal fossils were distinct from the mitochondrial DNA of people today—exactly as one would expect if H. sapiens replaced archaic human species without mating with them.

      Not all of the evidence fit with this tidy story, however. Many archaeologists think that the start of a cultural phase known as the Middle Stone Age (MSA) heralded the emergence of people who were beginning to think like us. Prior to this technological shift, archaic human species throughout the Old World made pretty much the same kinds of stone tools fashioned in the so-called Acheulean style. Acheulean technology centered on the production of hefty hand axes that were made by taking a chunk of stone and chipping away at it until it had the desired shape. With the onset of the MSA, our ancestors adopted a new approach to toolmaking, inverting the knapping process to focus on the small, sharp flakes they detached from the core—a more efficient use of raw material that required sophisticated planning. And they began attaching these sharp flakes to handles to create spears and other projectile weapons. Moreover, some people who made MSA tools also made items associated with symbolic behavior, including shell beads for jewelry and pigment for painting. A reliance on symbolic behavior, including language, is thought to be one of the hallmarks of the modern mind.

      The problem was that the earliest dates for the MSA were more than 250,000 years ago—far older than those for the earliest H. sapiens fossils at less than 200,000 years ago. Did another human species invent the MSA, or did H. sapiens actually evolve far earlier than the fossils seemed to indicate? In 2010 another wrinkle emerged. Geneticists announced that they had recovered nuclear DNA from Neandertal fossils and sequenced it. Nuclear DNA makes up the bulk of our genetic material. Comparison of the Neandertal nuclear DNA with that of living people revealed that non-African people today carry DNA from Neandertals, showing that H. sapiens and Neandertals did interbreed after all, at least on occasion.

      Subsequent ancient genome studies confirmed that Neandertals contributed to the modern human gene pool, as did other archaic humans. Further, contrary to the notion that H. sapiens originated within the past 200,000 years, the ancient DNA suggested that Neandertals and H. sapiens diverged from their common ancestor considerably earlier than that, perhaps upward of half a million years ago. If so, H. sapiens might have originated more than twice as long ago as the fossil record indicated.

Talking through Time

[This excerpt is from an article by Christine Kenneally in the September 2018 issue of Scientifi American.]]

      That language is uniquely human has been assumed for a long time. But trying to workout exactly how and why that is the case has been weirdly taboo. In the 1860s the Societe de Linguistique de Paris banned discussion about the evolution of language, and the Philological Society of London banned it in the 1870s. They may have wanted to clamp down on unscientific speculation, or perhaps it was a political move—either way, more than a century’s worth of nervousness about the subject followed. Noam Chomsky, the extraordinarily influential linguist at the Massachusetts Institute of Technology, was, for decades, rather famously disinterested in language evolution, and his attitude had a chilling effect on the field. Attending an undergraduate linguistics class in Melbourne, Australia, in the early 1990s, I asked my lecturer how language evolved. I was told that linguists did not ask the question, because it was not really possible to answer it.

      Luckily, just a few years later, scholars from different disciplines began to grapple with the question in earnest. The early days of serious research in language evolution unearthed a perplexing paradox: Language is plainly, obviously, uniquely human. It consists of wildly complicated interconnecting sets of rules for combining sounds and words and sentences to create meaning. If other animals had a system that was the same, we would likely recognize it. The problem is that after looking for a considerable amount of time and with a wide range of methodological approaches, we cannot seem to find anything unique in ourselves—either in the human genome or in the human brain—that explains language.

      To be sure, we have found biological features that are both unique to humans and important for language. For example, humans are the only primates to have voluntary control of their larynx: it puts us at risk of choking, but it allows us to articulate speech. But the equipment that seems to be designed for language never fully explains its enormous complexity and utility.

Space for Nature

[These excerpts are from an editorial by Jonathan Baillie and Ya-Ping Zhang in the September 14, 2018, issue of Science.]

      How much of the planet should we leave for other forms of life? This is a question humanity must now grapple with. The global human population is 7.6 billion and anticipated to increase to around 10 billion by the middle of the century. Consumption is also projected to increase, with demands for food and water more than doubling by 2050. Simply put, there is finite space and energy on the planet, and we must decide how much of it we’re willing to share. This question requires deep consideration as it will determine the fate of millions of species and the health and well-being of future generations.

      About 20% of the world’s vertebrates and plants are threatened with extinction, mostly because humans have degraded or converted more than half of the terrestrial natural habitat. Moreover, we are harnessing biomass from other forms of life and converting it into crops and animals that are more useful to us. Livestock now constitute 60% of the mammalian biomass and humans another 36%. Only 4% remains for the more than 5000 species of wild mammals. This ratio is not surprising: Wild vertebrate populations have declined by more than 50% since 1970. Both from an ethical and a utilitarian viewpoint, this depletion of natural ecosystems is extremely troubling.

      Most scientific estimates of the amount of space needed to safeguard biodiversity and preserve ecosystem benefits suggest that 25 to 75% of regions or major ecosystems must be protected. But estimating how much space is required to protect current levels of biodiversity and secure existing ecosystem benefits is challenging because of limited knowledge of the number of species on this planet, poor understanding of how ecosystems function or the benefits they provide, and growing threats such as climate change. Thus, spatial targets will be associated with great uncertainty. However, targets set too low could have major negative implications for future generations and all life. Any estimate must therefore err on the side of caution.

      Current levels of protection do not even come close to the required levels. Just less than half of Earth's surface remains relatively intact, but this land tends to be much less productive. Only 3.6% of the oceans and 14.7% of land are formally protected. Many of these protected areas are “paper parks,” meaning they are not effectively managed, and one-third of the terrestrial protected lands are under intense human pressure….

      If we truly want to protect biodiversity and secure critical ecosystem benefits, the world’s governments must set a much more ambitious protected area agenda and ensure it is resourced….This will be extremely challenging, but it is possible, and anything less will likely result in a major extinction crisis and jeopardize the health and well-being of future generations.

Decoding the Puzzle of Human Consciousness

[These excerpts are from an article by Susan Backmore in the September 2018 issue of Scientifi American.]

      Might we humans be the only species on this planet to be truly conscious? Might lobsters and lions, beetles and bats be unconscious automata, responding to their worlds with no hint of conscious experience? Aristotle thought so, claiming that humans have rational souls but that other animals have only the instincts needed to survive. In medieval Christianity the “great chain of being” placed humans on a level above soulless animals and below only God and the angels. And in the 17th century French philosopher Rene Descartes argued that other animals have only reflex behaviors. Yet the more biology we learn, the more obvious it is that we share not only anatomy, physiology and genetics with other animals but also systems of vision, hearing, memory and emotional expression. Could it really be that we alone have an extra special something—this marvelous inner world of subjective experience?

      The question is hard because although your own consciousness may seem the most obvious thing in the world, it is perhaps the hardest to study. We do not even have a clear definition beyond appealing to a famous question asked by philosopher Thomas Nagel back in 1971: What is it like to be a bat? Nagel chose bats because they live such very different lives from our own. We may try to imagine what it is like to sleep upside down or to navigate the world using sonar, but does it feel like anything at all? The crux here is this: If there is nothing it is like to be a bat, we can say it is not conscious. If there is something (anything) it is like for the bat, it is conscious. So is there?

      We share a lot with bats: we, too, have ears and can imagine our arms as wings. But try to imagine being an octopus. You have eight curly, grippy, sensitive arms for getting around and catching prey but no skeleton, and so you can squeeze yourself through tiny spaces. Only a third of your neurons are in a central brain; the rest are in the nerve cords in each of your eight arms, one for each arm. Consider: Is it like something to be a whole octopus, to be its central brain or to be a single octopus arm? The science of consciousness provides no easy way of finding out.

      Even worse is the "hard problem" of consciousness: How does subjective experience arise from objective brain activity? How can physical neurons, with all their chemical and electrical communications, create the feeling of pain, the glorious red of the sunset or the taste of fine claret? This is a problem of dualism: How can mind arise from matter? Indeed, does it?...

      When lobsters or crabs are injured, are taken out of water or have a claw twisted off, they release stress hormones similar to cortisol and corticosterone. This response provides a physiological reason to believe they suffer. An even more telling demonstration is that when injured prawns limp and rub their wounds, this behavior can be reduced by giving them the same painkillers as would reduce our own pain.

      The same is true of fish. When experimenters injected the lips of rainbow trout with acetic acid, the fish rocked from side to side and rubbed their lips on the sides of their tank and on gravel, but giving them morphine reduced these reactions. When zebra fish were given a choice between a tank with gravel and plants and a barren one, they chose the interesting tank. But if they were injected with acid and the barren tank contained a painkiller, they swam to the barren tank instead. Fish pain may be simpler or in other ways different from ours, but these experiments suggest they do feel pain.

      Some people remain unconvinced. Australian biologist Brian Key argues that fish may respond as though they are in pain, but this observation does not prove they are consciously feeling anything….

The Silent, Reasonable Majority Must Be Heard

[These excerpts are from an article by Joshua P. Starr in the September 2018 issue of Phi Delta Kappan.]

      …on days when Democrats and Republicans hold their primary elections, only the most partisan of voters tend to show up at their polling places. Most people stay home, allowing their least reasonable neighbors to cast the majority of the ballots.

      That’s often how things work in school systems, too. When they have to make important decisions, most superintendents — at least, the ones I know — try to bracket off their personal beliefs and preferences in order to weigh the issues fairly and make the best choices they can. But they have to do so in the face of intense pressure from their most aggressive and opinionated constituents. Let's just say that it’s rarely the more thoughtful and fair-minded parents and community members who launch Twitter storms, light up the phones, and march into the district office to make demands on the superintendent….

      Whatever the demographics and political makeup of the loudest people in the room, the question is, How do we ensure that the quieter voices get heard, too? Most parents are reasonable — silent, but reasonable. They want a quality education for their sons and daughters. They have hopes for and concerns about their schools. They want problems to be resolved in expeditious and practical ways. But they rarely testify at board meetings, email the superintendent, or buttonhole their elected officials at the supermarket….

      System and school leaders can’t stop partisans from organizing and advocating, nor can they stop rabid bloggers or shut down toxic email chains. But they can certainly do more to reach out to a wider and more diverse set of parents and community members, rather than sitting back and waiting to see who shows up at board meetings and gets in line for the microphone…

      To be sure, school system leaders need to listen to those people who choose to speak up. But those can’t be the only voices that matter. The majority of parents may be silent much of the time, but they have just as much of a right to be heard, and their kids are just as deserving of an excellent education. We must find ways to hear what they have to say, rather than listening only to those who push and shove their way into our offices and board meetings.

It’s Time to Redefine the Federal Role in K-12 Education

[These excerpts are from an article by Jack Jenning in the September 2018 issue of Phi Delta Kappan.]

      What matters most in education? At its core, education comes down to a student, a teacher, and something to be taught and learned. Everything else (e.g., testing, accountability systems, and teacher evaluations) is secondary, having an indirect influence, at best, on what happens in the classroom. A person with the desire and readiness to learn, another person with the knowledge and skills to foster that learning, and the material to be learned. These are the fundamental elements of education (along with that additional element, money, without which public schooling cannot function), and they should be the starting points for any new federal policy agenda:

      No state has yet come close to ensuring that all young children enter school with the early math, literacy, and other skills that will allow them to succeed. A wealth of research shows that high-quality pre-school programs tend to be extraordinarily effective in helping kids become ready for kindergarten, but access to preschool is woefully inadequate in most of the country, especially for children from families below the middle class. Further, the quality of existing programs is wildly uneven, and many programs lack essential components that might enable them to improve, such as well-educated teachers, adequate salaries, careful teacher supervision, and assessment tools….

      An equally pressing problem, which states have shown little ability to solve on their own, has to do with raising the quality of the teaching force, which will require efforts to improve teacher recruitment, preparation, and retention. In each of these areas, we have failed to keep pace with other developed nations….Similarly, if we were serious about teacher recruitment, quality, and reten-tion, would we pay our teachers such meager wages? On average, teacher compensation is equivalent to about 60% of what comparably educated college graduates earn in other fields, whereas in most other developed countries, teacher pay is more or less comparable to that of college graduates….

      ...the federal government can and should (as it has done many times before) support curricular improvements in literacy, math, science, civics, language learning, and other subject areas.

      Finally, the funding of public education needs to be overhauled, but few states have shown the will or capacity to make meaningful changes, particularly when it comes to the distribution of resources among school districts….the American approach to school funding now stands out as one of the most dysfunctional systems in the world:

      If we want to make serious improvements in the areas of preschool education, teacher quality; and curriculum, then federal policy should address these things directly. And, in fact, while federal policy makers are often reluctant to fund programs that focus on teaching and curriculum — fearing that this would intrude on local control — there are a number of precedents for doing so….

      At the very least, policy advocates on all sides must recognize two basic truths about American education today: First, to ensure the future prosperity and cohesion of our nation, we must help our students achieve at higher levels than in the past; second, our schools do not currently provide all students with equal opportunities to become well educated. Given the urgency of the challenges posed, our politicians, educators, parents, business leaders, and other citizens must seek common ground on plausible solutions. We must get going, and fast.

Fake America Great Again

[These excerpts are from an article by Will Knight in the September/October 2018 issue of Technology Review.]

      These advances threaten to further blur the line between truth and fiction in politics. Already the internet accelerates and reinforces the dissemination of disinformation through fake social-media accounts. “Alternative facts” and conspiracy theories are common and widely believed. Fake news stories, aside from their possible influence on the last US presidential election, have sparked ethnic violence in Myanmar and Sri Lanka over the past year. Now imagine throwing new kinds of real-looking fake videos into the mix: politicians mouthing nonsense or ethnic insults, or getting caught behaving inappropriately on video—except it never really happened.…

      Are we about to enter an era when we can’t trust anything, even authentic-looking videos that seem to capture real “news”? How do we decide what is credible? Whom do we trust?

      Several technologies have converged to make fakery easier, and they’re readily accessible: smartphones let anyone capture video footage, and powerful computer graphics tools have become much cheaper. Add artificial-intelligence software, which allows things to be distorted, remixed, and synthesized in mind-bending new ways. AI isn’t just a better version of Photoshop or iMovie. It lets a computer learn how the world looks and sounds so it can conjure up convincing simulacra….

      There are well-established methods for identifying doctored images and video. One option is to search the web for images that might have been mashed together. A more technical solution is to look for telltale changes to a digital file, or to the pixels in an image or a video frame. An expert can search for visual inconsistencies—a shadow that shouldn’t be there, or an object that's the wrong size….

      In April, a supposed BBC news report announced the opening salvos of a nuclear conflict between Russia and NATO. The clip, which began circulating on the messaging platform WhatsApp, showed footage of missiles blasting off as a newscaster told viewers that the German city of Mainz had been destroyed along with parts of Frankfurt.

      It was, of course, entirely fake, and the BBC rushed to denounce it. The video wasn’t generated using AI, but it showed the power of fake video, and how it can spread rumors at warp speed. The proliferation of AI programs will make such videos far easier to make, and even more convincing.

      Even if we aren't fooled by fake news, it might have dire consequences for political debate. Just as we are now accustomed to questioning whether a photograph might have been Photoshopped, AI-generated fakes could make us more suspicious about events we see shared online. And this could contribute to the further erosion of rational political debate.

      In The Death of Truth, published this year, the literary critic Michiko Kakutani argues that alternative facts, fake news, and the general craziness of modern politics represent the culmination of cultural currents that stretch back decades. Kakutani sees hyperreal Al fakes as just the latest heavy blow to the concept of objective reality….

      Perhaps the greatest risk with this new technology, then, is not that it will be misused by state hackers, political saboteurs, or Anonymous, but that it will further undermine truth and objectivity itself. If you can’t tell a fake from reality, then it becomes easy to question the authenticity of anything. This already serves as a way for politicians to evade accountability.

      President Trump has turned the idea of fake news upside down by using the term to attack any media reports that criticize his administration. He has also suggested that an incriminating clip of him denigrating women, released during the 2016 campaign, might have been digitally forged. This April, the Russian government accused Britain of faking video evidence of a chemical attack in Syria to justify proposed military action. Neither accusation was true, but the possibility of sophisticated fakery is increasingly diminishing the credibility of real information. In Myanmar and Russia new legislation seeks to prohibit fake news, but in both cases the laws may simply serve as a way to crack down on criticism of the government….

      The truth will still be out there. But will you know it when you see it?

No, Big Tech Didn’t Make Us Polarized (But It Sure Helps)

[These excerpts are from an article by Adam Piore in the September/October 2018 issue of Technology Review.]

      …the most concerning problem highlighted by the 2016 election isn’t that the Russians used Twitter and Facebook to spread propaganda, or that the political consulting firm Cambridge Analytica illicitly gained access to the private information of more than 50 million Facebook users. It's that we have all, quite voluntarily, retreated into hyperpartisan virtual corners, owing in no small part to social media and internet companies that determine what we see by monitoring what we have clicked on in the past and giving us more of the same. In the process, opposing perspectives are sifted out, and we’re left with content that reinforces what we already believe.

      This is the famous “filter bubble,” a concept popularized in the 2011 book of the same name by Eli Pariser, an internet activist and founder of the viral video site Upworthy. “Ultimately, democracy works only if we citizens are capable of thinking beyond our narrow self-interest,” wrote Pariser. “But to do so, we need a shared view of the world we coinhabit. The filter bubble pushes us in the opposite direction—it creates the impression that our narrow self-interest is all that exists.”

      Or does it? The research suggests that things are not quite that simple.

      The legal scholar Cass Sunstein warned way back in 2007 that the internet was giving rise to an “era of enclaves and niches.” He cited a 2005 experiment in Colorado in which 60 Americans from conservative Colorado Springs and liberal Boulder, two cities about 100 miles apart, were assembled into small groups and asked to deliberate on three controversial issues (affirmative action, gay marriage, and an international treaty on global warming). In almost every case, people held more extreme positions after they spoke with like-minded others….

      Data from the polling firm Pew backs up the idea that polarization doesn’t come just from the internet. After the 2016 election, Pew found that 62 percent of Americans got news from social-media sites, but—in a parenthetical ignored in most articles about the study—only 18 percent said they did so “often.” A more recent Pew study found that only about 5 percent said they had “a lot” of trust in the information.

      “The internet is absolutely not the causal factor here,” says Ethan Zuckerman, who directs MIT’s Center for Civic Media….

      Lousy results such as this have led Zuckerman toward a more radical idea for countering filter bubbles: the creation of a taxpayer-funded social-media platform with a civic mission to provide a “diverse and global view of the world.”

      The early United States, he noted in an essay for the Atlantic, featured a highly partisan press tailored to very specific audiences. But publishers and editors for the most part abided by a strong cultural norm, republishing a wide range of stories from different parts of the nation and reflecting different political leanings. Public broadcasters in many democracies have also focused on providing a wide range of perspectives. It’s not realistic, Zuckerman argues, to expect the same from outlets like Facebook: their business model drives them to pander to our natural human desire to congregate with others like ourselves. A public social-media platform with a civic mission, says Zuckerman, could push unfamiliar perspectives into our feeds and push us out of our comfort zones. Scholars could review algorithms to make sure we’re seeing an unbiased representation of views. And yes, he admits, people would complain about publicly funding such a platform and question its even-handedness. But given the lack of other viable solutions, he says, it’s worth a shot.

      …if a Republican politician tells people that immigrants are moving in and changing the culture or taking locals’ jobs, or if a Democrat tells female students that Christian activists want to ban women’s rights, their words have power. Bavel’s research suggests that if you want to overcome partisan divisions, avoid the intellect and focus on the emotions….

      Maybe in the end it’s up to us to decide to expose ourselves to content from a wider array of sources, and then to engage with it. Sound unappealing? Well, consider the alternative: your latest outraged political post didn’t accomplish much, because the research shows that anyone who read it almost certainly agreed with you already.

The Road from Tahrir to Trump

[These excerpts are from an article by Zeynep Tufekci in the September/October 2018 issue of Technology Review.]

      Digital platforms allowed communities to gather and form in new ways, but they also dispersed existing communities, those that had watched the same TV news and read the same newspapers. Even living on the same street meant less when information was disseminated through algorithms designed to maximize revenue by keeping people glued to screens. It was a shift from a public, collective politics to a more private, scattered one, with political actors collecting more and more personal data to figure out how to push just the right buttons, person by person and out of sight….

      The US National Security Agency had an arsenal of hacking tools based on vulnerabilities in digital technologies—bugs, secret backdoors, exploits, shortcuts in the (very advanced) math, and massive computing power. These tools were dubbed “nobody but us” (or NOBUS, in the acronym-loving intelligence community), meaning no one else could exploit them, so there was no need to patch the vulnerabilities or make computer security stronger in general. The NSA seemed to believe that weak security online hurt its adversaries a lot more than it hurt the NSA.

      That confidence didn't seem unjustified to many. After all, the internet is mostly an American creation; its biggest companies were founded in the United States. Computer scientists from around the world still flock to the country, hoping to work for Silicon Valley. And the NSA has a giant budget and, reportedly, thousands of the world's best hackers and mathematicians….

      There doesn’t seem to have been a major realization within the US's institutions—its intelligence agencies, its bureaucracy, its electoral machinery—that true digital security required both better technical infrastructure and better public awareness about the risks of hacking, meddling, misinformation, and more. The US's corporate dominance and its technical wizardry in some areas seemed to have blinded the country to the brewing weaknesses in other, more consequential ones….

      Though smaller than Facebook and Google, Twitter played an outsize role thanks to its popularity among journalists and politically engaged people. Its open philosophy and easygoing approach to pseudonyms suits rebels around the world, but it also appeals to anonymous trolls who hurl abuse at women, dissidents, and minorities. Only earlier this year did it crack down on the use of bot accounts that trolls used to automate and amplify abusive tweeting.

      Twitter’s pithy, rapid-fire format also suits anyone with a professional or instinctual understanding of attention, the crucial resource of the digital economy.

      Say, someone like a reality TV star. Someone with an uncanny ability to come up with belittling, viral nicknames for his opponents, and to make boastful promises that resonated with a realignment in American politics—a realignment mostly missed by both Republican and Democratic power brokers.

      Donald Trump, as is widely acknowledged, excels at using Twitter to capture attention. But his campaign also excelled at using Facebook as it was designed to be used by advertisers, testing messages on hundreds of thousands of people and microtargeting them with the ones that worked best. Facebook had embedded its own employees within the Trump campaign to help it use the platform effectively (and thus spend a lot of money on it), but they were also impressed by how well Trump himself performed. In later internal memos, reportedly, Facebook would dub the Trump campaign an “innovator” that it might learn from. Facebook also offered its services to Hillary Clinton’s campaign, but it chose to use them much less than Trump’s did.

      …they started posting materials aimed at fomenting polarization. The Russian trolls posed as American Muslims with terrorist sympathies and as white supremacists who opposed immigration. They posed as Black Lives Matter activists exposing police brutality and as people who wanted to acquire guns to shoot police officers. In so doing, they not only fanned the flames of division but provided those in each group with evidence that their imagined opponents were indeed as horrible as they suspected. These trolls also incessantly harassed journalists and Clinton supporters online, resulting in a flurry of news stories about the topic and fueling a (self-fulfilling) narrative of polarization among the Democrats….

      Second, the new, algorithmic gatekeepers aren’t merely (as they like to believe) neutral conduits for both truth and falsehood. They make their money by keeping people on their sites and apps; that aligns their incentives closely with those who stoke outrage, spread misinformation, and appeal to people’s existing biases and preferences….

      Third, the loss of gatekeepers has been especially severe in local journalism. While some big US media outlets have managed (so far) to survive the upheaval wrought by the internet, this upending has almost completely broken local newspapers, and it has hurt the industry in many other countries. That has opened fertile ground for misinformation. It has also meant less investigation of and accountability for those who exercise power, especially at the local level. The Russian operatives who created fake local media brands across the US either understood the hunger for local news or just lucked into this strategy. Without local checks and balances, local corruption grows and trickles up to feed a global corruption wave playing a major part in many of the current political crises….

      This is also how Russian operatives fueled polarization in the United States, posing simultaneously as immigrants and white supremacists, angry Trump supporters and “Bernie bros.” The content of the argument didn't matter; they were looking to paralyze and polarize rather than convince. Without old-style gatekeepers in the way, their messages could reach anyone, and with digital analytics at their fingertips, they could hone those messages just like any advertiser or political campaign….

      Ubiquitous digital surveillance should simply end in its current form. There is no justifiable reason to allow so many companies to accumulate so much data on so many people. Inviting users to “click here to agree” to vague, hard-to-pin-down terms of use doesn’t produce “informed consent.” If, two or three decades ago, before we sleepwalked into this world, a corporation had suggested so much reckless data collection as a business model, we would have been horrified.

      There are many ways to operate digital services without siphoning up so much personal data. Advertisers have lived without it before, they can do so again, and it's probably better if politicians can’t do it so easily. Ads can be attached to content, rather than directed to people….

      But we didn’t get where we are simply because of digital technologies. The Russian government may have used online platforms to remotely meddle in US elections, but Russia did not create the conditions of social distrust, weak institutions, and detached elites that made the US vulnerable to that kind of meddling.

      Russia did not make the US (and its allies) initiate and then terribly mishandle a major war in the Middle East, the after-effects of which—among them the current refugee crisis—are still wreaking havoc, and for which practically nobody has been held responsible. Russia did not create the 2008 financial collapse: that happened through corrupt practices that greatly enriched financial institutions, after which all the culpable parties walked away unscathed, often even richer, while millions of Americans lost their jobs and were unable to replace them with equally good ones.

      Russia did not instigate the moves that have reduced Americans’ trust in health authorities, environmental agencies, and other regulators. Russia did not create the revolving door between Congress and the lobbying firms that employ ex-politicians at handsome salaries. Russia did not defimd higher education in the United States. Russia did not create the global network of tax havens in which big corporations and the rich can pile up enormous wealth while basic government services get cut.

      These are the fault lines along which a few memes can play an outsize role. And not just Russian memes: whatever Russia may have done, domestic actors in the United States and Western Europe have been eager, and much bigger, participants in using digital platforms to spread viral misinformation.

      Even the free-for-all environment in which these digital platforms have operated for so long can be seen as a symptom of the broader problem, a world in which the powerful have few restraints on their actions while everyone else gets squeezed. Real wages in the US and Europe are stuck and have been for decades while corporate profits have stayed high and taxes on the rich have fallen. Young people juggle multiple, often mediocre jobs, yet find it increasingly hard to take the traditional wealth-building step of buying their own home—unless they already come from privilege and inherit large sums.

      If digital connectivity provided the spark, it ignited because the kindling was already everywhere. The way forward is not to cultivate nostalgia for the old-world information gatekeepers or for the idealism of the Arab Spring. It’s to figure out how our institutions, our checks and balances, and our societal safeguards should function in the 21st century—not just for digital technologies but for politics and the economy in general. This responsibility isn’t on Russia, or solely on Facebook or Google or Twitter. It’s on us.

Controlling Cholera with Microbes

[These excerpts are from an article by Anne Trafton in the September/October 2018 issue of MIT News.]

      MIT engineers have developed a mix of natural and engineered bacteria designed to diagnose and treat cholera, an intestinal infection that causes severe dehydration.

      Cholera outbreaks are usually caused by contaminated drinking water, and infections can be fatal if not treated. The most common treatment is rehydration, which must be done intravenously if the patient is extremely dehydrated. However, intravenous treatment is not always available, and the disease kills an estimated 95,000 people per year.

      The MIT team’s new probiotic mix could be consumed regularly as a preventive measure in regions where cholera is common, but it could also be used to treat people soon after infection occurs….

      The researchers chose Lactococcus lactis, a strain of bacteria used to make cheese, and engineered into it a genetic circuit that detects a molecule produced by Vibrio cholerae, the microbe that causes cholera. When engineered L. lactis encounters this molecule, it turns on an enzyme that produces a red color detectable in stool samples.

      Serendipitously, while working on a way to further engineer L. lactis so that it could treat infections, the researchers discovered that the unmodified bacterium can kill cholera microbes by producing lactic acid. This natural metabolic by-product makes the gastrointestinal environment more acidic, inhibiting the growth of V. cholerae.

      In tests in mice, the researchers found that a mixture of engineered and unmodified L. lactis could successfully prevent cholera from developing and could also treat existing infections. The MIT team is now exploring the possibility of using this approach to combat other microbes.

Smog Patrol

[These excerpts are from an article by Peter Dizikes in the September/October 2018 issue of MIT News.]

      The Chinese government has implemented measures to clean up the air pollution that has smothered its cities for decades. Are they effective? A study coauthored by an MIT scholar shows that one key antipollution law is indeed working—but unevenly.

      The study examines a Chinese law, in effect since 2014, requiring coal-fired power plants to significantly reduce emissions of sulfur dioxide, a pollutant associated with respiratory illnesses. Overall, the concentration of these emissions at coal power plants fell by 13.9 percent.

      However, the law also called for greater emissions reductions in more heavily polluted and more populous regions, and those “key” regions are precisely where plants may have been least compliant. Only 50 percent reported meeting the new standard, and remote data—as opposed to readings supplied by the plants themselves—suggests that the results were even worse….

      Data from the two monitoring systems corresponded closely in “non-key” regions, where the maximum allowable concentration of sulfur dioxide was lowered from 400 to 200 milligrams per cubic meter. But in the key regions, where the limit was placed at 50 milligrams per cubic meter, the research found no evidence of correspondence.

      That tougher standard may have been harder for power plants to meet….

Can a Transgenic Chestnut Restore a Forest Icon?

[These excerpts are from an article by Gabriel Popkin in the August 31, 2018, issue of Science.]

      Two deer-fenced plots here contain some of the world's most highly regulated trees. Each summer researchers double-bag every flower the trees produce. One bag, made of breathable plastic, keeps them from spreading pollen. The second, an aluminum mesh screen added a few weeks later, prevents squirrels from stealing the spiky green fruits that emerge from pollinated flowers. The researchers report their every move to regulators with the U.S. Department of Agriculture….

      These American chestnut trees (Castanea dentata) are under such tight security because they are genetically modified (GM) organisms, engineered to resist a deadly blight that has all but erased the once widespread species from North American forests….

      If the regulators approve the request, it would be “precedent setting”—the first use of a GM tree to try to restore a native species in North America…

      American chestnuts, towering 30 meters or more, once dominated forests throughout the Appalachian Mountains. But in the early 1900s, a fungal infection appeared on trees at the Bronx Zoo in New York City, and then spread rapidly. The so-called chestnut blight—an accidental import from Asia—releases a toxin that girdles trees and kills everything above the infection site, though still-living roots sometimes send up new shoots. By midcentury, large American chestnuts had all but disappeared.

Revolutionary Technologies

[This excerpt is from an editorial by Jeremy Berg in the August 31, 2018, issue of Science.]

      …New technology is one of the most powerful drivers of scientific progress. For example, the earliest microscopes magnified images only 50-fold at most. When the Dutch fabric merchant and amateur scientist Antonie van Leeuwenhoek developed microscopes with more than 200-fold magnifications (likely to examine cloth), he used them to study many items, including pond water and plaque from teeth. His observations of “animalcules” led to fundamental discoveries in microbiology and cell biology, and spurred the elaboration of improved microscopes. Today, various light microscopes remain prime tools in modern biology. This example embodies two characteristics of a revolutionary technology: a capability for addressing questions better than extant technologies, and the possibility of being utilized and adapted by many other investigators.

      The discovery of x-rays in 1895 ushered in a multifaceted revolution in imaging. As scientists sought to understand the nature of these electromagnetic waves, they realized that they were diffracted by crystals, establishing that the wavelengths of x-rays were comparable to the separation between atoms in crystals. In 1913, William Henry Bragg and his son William Lawrence Bragg found that diffraction patterns could be interpreted to reveal the arrangement of atoms in a crystal. The Braggs determined the structures of many simple substances, including table salt and diamond. Others began using similar techniques to reveal more complex structures of inorganic and organic compounds. In the late 1950s, these methods were extended to determine the structure of proteins, and eventually to larger proteins and protein complexes. Thousands of structures are now reported each year and are foundational to our understanding of biochemistry and cell biology. Technical innovations, improved commercial and shared-facility instrumentation, and powerful software continue to drive the x-ray crystallography revolution.

Voting for the Earth

[These excerpts are from an article by Erich Pica in the Summer 2018 issue of the Friends of the Earth Newsmagazine.]

      In poll after poll, Americans from across the political spectrum stress the importance of clean air, pristine water, protected wildlife, healthy food, preserved forests and prairies, and a stable climate.

      In one recent Gallup poll, 62 percent of Americans said they believe the government needs to do more for the environment and 76 percent would like to see a greater investment in alternative energy sources like solar and wind power.

      You’d never know the U.S. had such a consensus on the environment. Mainstream media coverage of environmental issues is spotty at best. National politicians on both sides of the aisle do little more than pay lip service to environmental issues…

      When environmentalists vote, it forces politicians to pay attention to environmental issues and act on them...or face losing their jobs.

      Unfortunately, too many people who care about the environment have been staying home on election day, giving politicians a free pass on issues affecting our planet.

      We simply can’t afford to let climate change and the environment fall to the bottom of the list any longer.

      We’re at a make-or-break point for our planet. We’ve endured several of history's warmest years in the last decade. The Arctic just experienced its warmest winter on record, with temperatures up to 36 degrees Fahrenheit higher than average. Wildfire and hurricane seasons have been more severe.

      Scientists estimate that we need to cut greenhouse gas emissions dramatically by 2050—to 80 percent below levels we saw in 1990— if we want to save ourselves from catastrophe.

      In short, we need to vote like our lives and our planet depend on it...because they do.

Putting Sleep Myths to Bed

[These excerpts are from an article by Adrian Woolfson in the August 24, 2018, issue of Science.]

      In humans, the master timekeeper underwriting the architecture of sleep is a small region buried deep within the brain, known as the suprachiasmatic nucleus. The pacemaker activity of this biological timepiece is controlled by several genes, which have names like Period, Clock, and Timeless. Mutations in these can transform us from night owls into morning larks or something in between. Fortunately, errant wanderings are typically adjusted by “zeitgebers”—literally, “time-givers”—principally in the form of blue light.

      In Nodding off, [Alice] Gregory makes the point that although sleep studies typically focus on individuals, sleep is not always a solitary pastime and may be adversely affected by our choice of bedmate. Indeed, sleep researchers are now attempting to address the reality that adults often do not sleep in isolation.

      The structure of sleep also changes across an individual’s lifetime. The sleep patterns of young children, for example, are profoundly influenced by their belief systems. Gregory cautions parents against sending misbehaving children to bed early because this association between sleep and punishment may inadvertently condemn them to years of insomnia.

      Similarly, she explains why the Sisyphean struggle to force teenagers to wake up early is invariably destined to fail. Their pattern of melatonin release differs to those of adults and children, and the recapitulation of this phenomenon in other mammals suggests that it has been hard-wired by evolution.

      While extolling the virtues of sleep and its fundamental importance to our health, Gregory reveals some interesting tidbits, including the fact that dolphins sleep with just half of their brain at a time and that male armadillos have erections during non-REM (rapid eye movement) sleep, unlike their human counterparts, who experience this phenomenon only during REM sleep. The heterogeneity of sleep across different species indicates its essential function but also how it may be modified to perform different functions.

      Although the precise function of sleep remains enigmatic, poor-quality sleep and sleep deprivation may have a profound impact on our health…..

      It is noteworthy, and apparently contrary to the central thesis of these two tomes, that genius has sometimes emerged within the context of abnormal sleep patterns. The serial micronapper Leonardo da Vinci’s remarkable canon of work, for example, was achieved on a sleeping pattern comprising naps of just 15 minutes taken every 4 hours….

Back to the Blackboard

[These excerpts are from an article by Jill Lepore in the September 10, 2018, issue of The New Yorker.]

      Is education a fundamental right? The Constitution, drafted in the summer of 1787, does not mention a right to education, but the Northwest Ordinance, passed by Congress that same summer, held that “religion, morality, and knowledge, being necessary to good government and the happiness of mankind, schools and the means of education shall forever be encouraged.” By 1868 the constitutions of twenty-eight of the thirty-two states in the Union had provided for free public education, open to all. Texas, in its 1869 constitution, provided for free public schooling for “all the inhabitants of this State,” a provision that was revised to exclude undocumented immigrants only in 1975.

      [Judge] Justice skirted the questions of whether education is a fundamental right and whether undocumented immigrants are a suspect class. Instead of applying the standard of “strict scrutiny” to the Texas law, he applied the lowest level of scrutiny to the law, which is known as the “rational basis test.” He decided that the Texas law failed this test. The State of Texas had argued that the law was rational because undocumented children are expensive to educate—they often require bilingual education, free meals, and even free clothing. But, Justice noted, so are other children, including native-born children, and children who have immigrated legally, and their families are not asked to bear the cost of their special education. As to why Texas had even passed such a law, he had two explanations, both cynical: “Children of illegal aliens had never been explicitly afforded any-judicial protection, and little political uproar was likely to be raised in their behalf.”

      In September, 1978, Justice ruled in favor of the children. Not long afterward, a small bouquet arrived at his house, sent by three Mexican workers. Then came the hate mail. A man from Lubbock wrote, on the back of a postcard, “Why in the hell don’t you illegally move to mexico?”

      …Later, [Supreme Court Justice] Marshall came back at him, asking, “Could Texas pass a law denying admission to the schools of children of convicts?” Hardy said that they could, but that it wouldn’t be constitutional. Marshall's reply: “We are dealing with children. I mean, here is a child that is the son of a murderer, but he can go to school, but the child that is the son of an unfortunate alien cannot?”

Ancient DNA Reveals Tryst between Extinct Human Species

[These excerpts are from an article by Gretchen Vogel in the August 24, 2018, issue of Science.]

      The woman may have been just a teenager when she died more than 50,000 years ago, too young to have left much of a mark on her world. But a piece of one of her bones, unearthed in a cave in Russia's Denisova valley in 2012, may make her famous. Enough ancient DNA lingered within the 2-centimeter fragment to reveal her startling ancestry: She was the direct offspring of two different species of ancient humans—neither of them ours….her mother was Neanderthal and her father was Denisovan, the mysterious group of ancient humans discovered in the same Siberian cave in 2011. It is the most direct evidence yet that various ancient humans mated with each other and had offspring.

      Based on other ancient genomes, researchers already had concluded that Denisovans, Neanderthals, and modern humans interbred in ice age Europe and Asia. The genes of both archaic human species are present in many people today. Other fossils found in the Siberian cave have shown that all three species lived there at different times….

      …the proportion of genes in which her chromosorne pairs harbored different variants—so-called heterozygous alleles—was close to 50% across all chromosomes, suggesting the maternal and paternal chromosomes came directly from different groups. And her mitochondrial DNA, which is inherited maternally, was uniformly Neanderthal, so the researchers concluded she was a first-generation hybrid of a Denisovan man and Neanderthal woman….

Retreat on Economics at the EPA

[These excerpts are from an editorial by Kevin Boyle and Matthew Kotchen in the August 24, 2018, issue of Science.]

      Rigorous economic analysis has long been recognized as essential for sound, defensible decision-making by government agencies whose regulations affect human health and the environment The acting administrator (since July 2018) of the U.S. Environmental Protection Agency (EPA) has emphasized the importance of transparency and public trust. These laudable goals are enhanced by external scientific review of the EPA’s analytical procedures. Yet, in June 2018, the EPA’s Science Advisory Board (SAB) eliminated its Environmental Economics Advisory Committee (EEAC). The agency should be calling for more—not less—external advice on economics, given the Trump administration’s promotion of economic analyses that push the boundaries of well-established best practices. The pattern is clear: When environmental regulations are expected to provide substantial public benefits, assumptions are made to substantially diminish their valuations.

      …today, many economic analyses that support the Trump administration’s regulatory rollbacks conflict with the EPA's previous findings. The 2017 analysis for eliminating the Waters of the United States rule turned favorable only after excluding all benefits of protecting wetlands. Eliminating the Clean Power Plan is supported in another 2017 analysis only after changing assumptions about the scope of climate damages, the measurement of health effects, and the impact on future generations. Differing assumptions also underlie the economic justification of the administration’s 2018 proposal to roll back automotive fuel economy standards.

Inside Our Heads

[These excerpts are from an article by Thomas Suddendorf in the September 2018 issue of Scientific American.]

      …It also turns out that animal and human cognition, though similar in many respects, differ in two profound dimensions. One is the ability to form nested scenarios, an inner theater of the mind that allows us to envision and mentally manipulate many possible situations and anticipate different outcomes. The second is our drive to exchange our thoughts with others. Taken together, the emergence of these two characteristics transformed the human mind and set us on a world-changing path.

      … animal studies have not met similar stringent criteria for establish-ing foresight, nor have they demonstrated deliberate practice. Does this mean we should conclude that animals do not have the relevant capacities at all? That would be premature. Absence of evidence is not evidence of absence, as the saying goes. Establishing competence in animals is difficult; establishing the absence of competence is even harder.

      Consider the following study, in which my colleague Jon Redshaw of the University of Queensland in Australia and I tried to assess one of the most fundamental aspects of thinking about the future: the recognition that it is largely uncertain. When one realizes that events may unfold in more than one way, it makes sense to prepare for various possibilities and to make contingency plans. Human hunters demonstrate this when they lay a trap in front of all their prey’s potential escape routes rather than just in front of one. Our simple test of this capacity was to show a group of chimpanzees and orangutans a vertical tube and drop a reward at the top so they could catch it at the bottom. We compared the apes’ performance with that of a group of human children aged two to four doing the same thing. Both groups readily anticipated that the reward would reappear at the bottom of the tube: they led their hand under the exit to prepare for the catch.

      Next, however, we made events a little harder to predict. The straight tube was replaced by an upside-down Y-shaped tube that had two exits. In preparation for the drop, the apes and the two-year-old children alike tended to cover only one of the potential exits and thus ended up catching the reward in only half of the trials. But four-year-olds immediately and consistently covered both exits with their hands, thus demonstrating the capacity to prepare for at least two mutually exclusive versions of an imminent future event. Between ages two and four, we could see this contingency planning increase. in frequency. We saw no such ability among the apes.

      This experiment does not prove, however, that apes and two-year-old humans have no understanding that the future can unfold in distinct ways. As I mentioned, there is a fundamental problem when it comes to showing the absence of a capacity. Perhaps the animals were not motivated, did not understand the basic task or could not coordinate two hands. Or maybe we simply tested the wrong individuals, and more competent animals might be able to pass.

      To truly prove this ability is absent, a scientist would have to test all animals, at all times, on some fool-proof task. Clearly, that is not practical. All we can do is give individuals the chance to demonstrate competence. If they consistently fail, we can become more confident that they really do not have the capacity in question, but even then, future work may prove that wrong….

      The earliest evidence of deliberate practice is more than a million years old. The Acheulean stone tools of Homo erectus some 1.8 million years ago already suggest considerable foresight, as they appeared to have been carried from one place to another for repeated use. Crafting these tools requires considerable knowledge about rocks and how to work them. At some sites, such as Olorgesailie in Kenya, the ground is still littered with shaped stones, raising the question of why our ancestors kept making more tools when there were plenty lying around. The answer is that they were probably practicing how to manufacture those tools. Once they were proficient, they could wander the plains knowing they could make a new tool if the old one broke. These ancestors were armed and ready to reload….

      None of this is an excuse for arrogance. It is, in fact, a call for care. We are the only creatures on this planet with these abilities. As Spider-Man’s Uncle Ben declared, communicating complex ideas in an urge to connect with his superhero nephew, “With great power comes great responsibility.”

An Evolved Uniqueness

[These excerpts are from an article by the Kevin Laland in the September 2018 issue of Scientific American.]

      Most people on this planet blithely assume, largely without any valid scientific rationale, that humans are special creatures, distinct from other animals. Curiously, the scientists best qualified to evaluate this claim have often appeared reticent to acknowledge the uniqueness of Homo sapiens, perhaps for fear of reinforcing the idea of human exceptionalism put forward in religious doctrines. Yet hard scientific data have been amassed across fields ranging from ecology to cognitive psychology affirming that humans truly are a remarkable species.

      The density of human populations far exceeds what would be typical for an animal of our size. We live across an extraordinary geographical range and control unprecedented flows of energy and matter: our global impact is beyond question. When one also considers our intelligence, powers of communication, capacity for knowledge acquisition and sharing—along with magnificent works of art, architecture and music we create—humans genuinely do stand out as a very different kind of animal. Our culture seems to separate us from the rest of nature, and yet that culture, too, must be a product of evolution.

      The challenge of providing a satisfactory scientific explanation for the evolution of our species’ cognitive abilities and their expression in our culture is what I call “Darwin’s Unfinished Symphony.” That is because Charles Darwin began the investigation of these topics some 150 years ago, but as he himself confessed, his understanding of how we evolved these attributes was in his own words “imperfect” and “fragmentary” Fortunately, other scientists have taken up the baton, and there is an increasing feeling among those of us who conduct research in this field that we are closing in on an answer.

      The emerging consensus is that humanity’s accomplishments derive from an ability to acquire knowledge and skills from other people. Individuals then build iteratively on that reservoir of pooled knowledge over long periods. This communal store of experience enables creation of ever more efficient and diverse solutions to life’s challenges. It was not our large brains, intelligence or language that gave us culture but rather our culture that gave us large brains, intelligence and language. For our species and perhaps a small number of other species, too, culture transformed the evolutionary process.

      The term “culture” implies fashion or haute cuisine, but boiled down to its scientific essence, culture comprises behavior patterns shared by members of a community that rely on socially transmitted information. Whether we consider automobile designs, popular music styles, scientific theories or the foraging of small-scale societies, all evolve through endless rounds of innovations that add incremental refinements to an initial baseline of knowledge. Perpetual, relentless copying and innovation—that is the secret of our species’ success….

      Animals also “innovate.” When prompted to name an innovation, we might think of the invention of penicillin by Alexander Fleming or the construction of the World Wide Web by Tim Berners-Lee. The animal equivalents are no less fascinating. My favorite concerns a young chimpanzee called Mike, whom primatologist Jane Goodall observed devising a noisy dominance display that involved banging two empty kerosene cans together. This exhibition thoroughly intimidated Mike’s rivals and led to him shooting up the social rankings to become alpha male in record time. Then there is the invention by Japanese carrion crows of using cars to crack open nuts. Walnuts shells are too tough for crows to crack in their beaks, but they nonetheless feed on these nuts by placing them in the road for cars to run over, returning to retrieve their treats when the lights turn red. And a group of starlings—birds famously fond of shiny objects used as nest decorations—started raiding a coin machine at a car wash in Fredericksburg, Va., and made off with, quite literally, hundreds of dollars in quarters….

      Such stories are more than just enchanting snippets of natural history. Comparative analyses reveal intriguing patterns in the social learning and innovation exhibited by animals. The most significant of these discoveries finds that innovative species, as well as animals most reliant on copying, possess unusually large brains (both in absolute terms and relative to body size). The correlation between rates of innovation and brain size was initially observed in birds, but St. Andrews in Scotland this research has since been replicated in primates….

      …The results suggested that natural selection does not favor more and more social learning but rather a tendency toward better and better social learning. Animals do not need a big brain to copy, but they do need a big brain to copy well.

      …Those primates that excel at social 11 learning and innovation are the same species that have the most diverse diets, use tools and extractive foraging, and exhibit the most complex social behavior. In fact, statistical analyses suggest that these abilities vary in lockstep so tightly that one can align primates along a single dimension of general cognitive performance, which we call primate intelligence (loosely analogous to IQ. in humans).

      Chimpanzees and orangutans excel in all these performance measures and have high primate intelligence, whereas some nocturnal prosimians are poor at most of them and have a lower metric. The strong correlations between primate intelligence and both brain size measures and performance in laboratory tests of learning and cognition validate the use of the metric as a measure of intelligence….

      Cultural drive is not the only cause of primate brain evolution: diet and sociality are also important because fruit-eating primates and those living in large, complex groups possess large brains. It is difficult, however, to escape the conclusion that high intelligence and longer lives co-evolved in some primates because their cultural capabilities allowed them to exploit high-quality but difficult-to-access food resources, with the nutrients gleaned “paying” for brain growth. Brains are energetically costly organs, and social learning is paramount to animals gathering the resources necessary to grow and maintain a large brain efficiently.

      …Why haven’t chimpanzees sequenced genomes or built space rockets? Mathematical theory has provided some answers. The secret comes down to the fidelity of information transmission from one member of a species to another, the accuracy with which learned information passes between transmitter and receiver. The size of a species’ cultural repertoire and how long cultural traits persist in a population both increase exponentially with transmission fidelity. Above a certain threshold, culture begins to ratchet up in complexity and diversity. Without accurate transmission, cumulative culture is impossible. But once a given threshold is surpassed, even modest amounts of novel invention and refinement lead rapidly to massive cultural change. Humans are the only living species to have passed this threshold.

      Our ancestors achieved high-fidelity transmission through teaching—behavior that functions to facilitate a pupil's learning. Whereas copying is widespread in nature, teaching is rare, and yet teaching is universal in human societies once the many subtle forms this practice takes are recognized….

      …Agriculture freed societies from the constraints that the peripatetic lives of hunter-gatherers imposed on population size and any inclinations to create new technologies. In the absence of this constraint, agricultural societies flourished, both because they outgrew hunter-gatherer communities through allowing an increase in the carrying capacity of a particular area for food production and because agriculture triggered a raft of associated innovations that dramatically changed human society. In the larger societies supported by increasing farming yields, beneficial innovations were more likely to spread and be retained. Agriculture precipitated a revolution not only by triggering the invention of related technologies—ploughs or irrigation technology, among others—but also by spawning entirely unanticipated initiatives, such as the wheel, city-states and religions.

      The emerging picture of human cognitive evolution suggests that we are largely creatures of our own making. The distinctive features of humanity—our intelligence, creativity, language, as well as our ecological and demographic success—are either evolutionary adaptations to our ancestors' own cultural activities or direct consequences of those adaptations. For our species' evolution, cultural inheritance appears every bit as important as genetic inheritance.

      We tend to think of evolution through natural selection as a process in which changes in the external environment, such as predators, climate or disease, trigger evolutionary refinements in an organism’s traits. Yet the human mind did not evolve in this straightforward way. Rather our mental abilities arose through a convoluted, reciprocal process in which our ancestors constantly constructed niches (aspects of their physical and social environments) that fed back to impose selection on their bodies and minds, in endless cycles….But our ability to think, learn, communicate and control our environment makes humanity genuinely different from all other animals.

The So-Called Right to Try

[These excerpts are from an article by the Claudia Wallis in the September 2018 issue of Scientific American.]

      There’s no question about it: the new law sounds just great. President Donald Trump, who knows a thing or two about marketing, gushed about its name when he signed the “Right to Try” bill into law on May 30. He was surrounded by patients with incurable diseases, including a second grader with Duchenne muscular dystrophy, who got up from his small wheelchair to hug the president. The law aims to give such patients easier access to experimental drugs by bypassing the Food and Drug Administration.

      The crowd-pleasing name and concept are why 40 states had already passed similar laws, although they were largely symbolic until the federal government got onboard. The laws vary but generally say that dying patients may seek from drugmakers any medicine that has passed a phase I trial---a minimal test of safety. “We’re going to be saving tremendous numbers of lives,” Trump said. “The current FDA approval process can take many, many years. For countless patients, time is not what they have.”

      But the new law won’t do what the president claims. Instead it gives false hope to the most vulnerable patients….

      In fact, for decades pharmaceutical companies have made unapproved drugs available through programs overseen by the FDA. This “expanded access” is aimed at extremely ill patients who, for one reason or another, do not qualify for formal drug studies. A 2016 report shows that the FDA receives more than 1,000 annual requests on behalf of such patients and approves 99.7 percent of them. It acts immediately in emergency cases or else within days, according to FDA commissioner Scott Gottlieb.

      Of course, there are barriers to getting medicines that may not be effective or safe. Some patients cannot find a doctor to administer them or an institution that will let them be used on-site. And many of these drugs are simply not made available. Drugmakers cannot be compelled to do so: a 2007 federal court decision found “there is no fundamental right... of access to experimental drugs for the terminally ill.” The new law changes none of this….

      Unethical companies, however, may find fresh opportunities to prey on desperate patients under the new law. It releases doctors, hospitals and drugmakers from liability. And although it stipulates that manufacturers can charge patients only what it costs to provide the drug, there is no required preapproval of these charges by the FDA, as there is with expanded access. Such issues led dozens of major patient-advocacy groups to oppose the legislation, which was originally drafted and promoted by the Goldwater Institute, a libertarian think tank.

Oil in Your Wine

[These excerpts are from an article by the Lucas Laursen in the September 2018 issue of Scientific American.]

      Every great bottle of wine begins with a humble fungal infection. Historically, wine-makers relied on naturally occurring yeasts to convert grape sugars into alcohol; modern vintners typically buy one of just a few laboratory-grown strains. Now, to set their products apart, some of the best winemakers are revisiting nature’s lesser-used microbial engineers. Not all these strains can withstand industrial production processes and retain their efficacy—but a natural additive offers a possible solution, new research suggests.

      Industrial growers produce yeast in the presence of oxygen, which can damage cell walls and other important proteins during a process called oxidation. This can make it harder for yeasts—which are dehydrated for shipping—to perform when winemakers revive them. Biochemist Emilia Matallana of the University of Valencia in Spain and her colleagues have been exploring practical ways to fend off such oxidation for years. After showing that pure antioxidants worked, they began searching for a more affordable natural source. They found it in argan, an olivelike fruit used for food and cosmetics. The trees it grows on are famously frequented by domesticated goats.

      Matallana and her team treated three varieties of wine yeast (Saccharomyces cerevisiae) with argan oil, dehydrated them and later rehydrated them. The oil protected important proteins in the yeasts from oxidation and boosted wine fermentation….

      Microbiologists are now interested in 1 studying how and why each yeast strain responded to the argan oil as it did….The oil may one day enable vintners to use I a wider range of specialized yeasts, putting more varied wines on the menu. As for how the oil affected the wine's taste, Matallana says it was “nothing weird.”

Why Sex Matters in Alzheimer’s

[This excerpt is from an article by Rebecca Nebel in the September 2018 issue of Scientific American.]

      Growing older may be inevitable, but getting Alzheimer’s disease is not. Although we can’t stop the aging process, which is the biggest risk factor for Alzheimer’s, there are many other factors that can be modified to lower the risk of dementia.

      Yet our ability to reduce Alzheimer’s risk and devise new strategies for prevention and treatment is impeded by a lack of knowledge about how and why the disease differs between women and men. There are tantalizing hints in the literature about factors that act differently between the sexes, including hormones and specific genes, and these differences could be important avenues of research. Unfortunately, in my experience, most studies of Alzheimer’s risk combine data for women and men….

      Risk factors are just one of the areas in which we need more research into the differences between the sexes in Alzheimer’s. Scientists have often overlooked sex differences in diagnosis, clinical trial design, treatment outcomes and caregiving. This bias has impeded progress in detection and care.

      Approaches that incorporate sex differences into research have advanced innovation in respect to many diseases. We need to do the same in Alzheimer’s. Looking at these differences will greatly enhance our understanding of this thief of minds and improve health outlooks for all.

Creative Science

[These excerpts are from an editorial by Steve Metz in the September 2018 issue of The Science Teacher.]

      In his famous 1959 Rede lecture, the chemist and novelist C. P. Snow lamented the modern creation of “Two Cultures,” one scientific and technical, the other humanistic and artistic. But it seems clear that science and the arts both spring from the same deep well of human creativity and imagination, as Richard Holmes explains in his wonderful book, The Age of Wonder. Holmes describes the deep connection Enlightenment scientists like astronomers Caroline and William Herschel, physicist Michael Faraday, and chemists Antoine Lavoisier and Sir Humphry Davies (who was also a published poet) had with Romantic artists, including the poets Samuel Coleridge and John Keats, the novelist Mary Shelley, and others.

      Job security increasingly requires imagination and creativity. As routine tasks become digitized and automated, successful workers will be those who imagine and create. Along with critical thinking, communication, and collaboration, creativity is one of the “Four Cs”—the 21st century learning and innovation skills that prepare students for increasingly complex life and work environments….It’s also at the apex of Bloom's taxonomy of learning objectives….

      Students often associate creativity with painting, music, and writing, but not with science. They think that scientists and engineers follow routine procedures and that science itself is a set of facts and vocabulary to memorize. And who can blame them? Too often their science classes involve passive note-taking, rote memorization, and step-by-step laboratory activities designed to produce a single right answer.

Our Looming Lead Problem

[These excerpts are from an article by Frederick Rowe Davis in the August 17, 2018, issue of Science.]

      On 25 April 2014, Flint Mayor Dayne Walling ceremoniously shut off a valve to the Detroit water supply and opened the flow of the Flint River into local homes and businesses. He marked the occasion by drinking from a glass filled with water from the new source. Eighteen months later, the water supply was switched back to Detroit. What occurred in between—the city’s failure to control infrastructure corrosion, the deterioration of fresh water entering Flint residences, citizen complaints, government denials, elevated lead levels in children, and public outcry—would become the basis for a crisis that rose to national attention in 2015….

      But the story of Flint is also one of resilience. Residents rose up and challenged the indifference and false palliatives offered by the authorities, who for many months proclaimed that the water supply in Flint was safe for drinking….

      The water crisis in Flint is profoundly worrisome: Numerous children suffered lead poisoning as a direct result of a bureaucratic focus on the fiscal rather than the social. With the huge amount of lead incorporated into the nation's infrastructure, many other communities are just a few poor decisions from a similar fate.

Global Warming Policy: Is Population Left Out in the Cold?

[These excerpts are from an article by John Bongaarts and Brian C. O’Neill in the August 17, 2018, issue of Science.]

      Would slowing human population growth lessen future impacts of anthropogenic climate change? With an additional 4 billion people expected on the planet by 2100, the answer seems an obvious “yes.” Indeed, substantial scientific literature backs up this intuition. Many nongovernmental organizations undertake climate- and population-related activities, and national adaptation plans for most of the least-developed countries recognize population growth as an important component of vulnerability to climate impacts. But despite this evidence, much of the climate community, notably the Intergovernmental Panel on Climate Change (IPCC), the primary source of scientific information for the international climate change policy process, is largely silent about the potential for population policy to reduce risks from global warming. Though the latest IPCC report includes an assessment of technical aspects of ways in which population and climate change influence each other, the assessment does not extend to population policy as part of a wide range of potential adaptation and mitigation responses. We suggest that four misperceptions by many in the climate change community play a substantial role in neglect of this topic, and propose remedies for the IPCC as it prepares for the sixth cycle of its multiyear assessment process.

      Population-related policies—such as offering voluntary family planning services as well as improved education for women and girls—can have many of the desirable characteristics of climate response options: benefits to both mitigation and adaptation, co-benefits with human well-being and other environmental issues, synergies with Sustainable Development Goals (SDGs), and cost effectiveness. These policies can also enable women to achieve their desired family size, and lead to lower fertility and slower population growth. The resulting demographic changes can not only lessen the emissions that drive climate change but also improve the ability of populations to adapt to its consequences.





Administrators: Be Intentional ‘For All’

[These excerpts are from an editorial by Sharon Delesbore in the September 2018 issue of NSTA Reports.]

      School district leaders and campus administrators must take the helm and realize that science instruction must be a priority for a sustainable society. Because science understanding is not assessed as frequently as math and reading—and often left out of funding calculations—its importance has been woefully negated, and our workforce is suffering from lack of qualified science-literate candidates. Even more dismal is the rarity of science-literate candidates from underrepresented populations in the global schema. This is not just about ethnicity or low socioeconomic status, but also about access, now more than ever.

      …What I do not see is an influx of campus administrators seeking opportunities to develop their capacity in science education to support their teachers.

      As educators and humans in general, we tend to focus on and assist in areas in which we are strong, confident, and successful. When math or science is discussed, the common comments are “I was not good at that,” or “Those subjects scare me.” Many adults believe science and math are difficult subjects and transfer those beliefs to their children at an early age, inadvertently laying the foundation for barriers for their children. Combined with the negative reinforcement of little or poor experiences with science engagement, they are creating a formula for STEM evasion.

Clinical Trials Need More Diversity

[This excerpt is from an editorial by the editors in the September 2018 issue of Scientific American.]

      Nearly 40 percent of Americans belong to a racial or ethnic minority, but the patients who participate in clinical trials for new drugs skew heavily white—in some cases, 80 to 90 percent. Yet nonwhite patients will ultimately take the drugs that come out of clinical studies, and that leads to a real problem. The symptoms of conditions such as heart disease, cancer and diabetes, as well as the contributing factors, vary across lines of ethnicity, as they do between the sexes. If diverse groups aren’t part of these studies, we can't be sure whether the treatment will work in all populations or what side effects might emerge in one group or another.

      This isn’t a new concern. In 1993 Congress passed the National Institutes of Health Revitalization Act, which required the agency to include more women and people of color in their research studies. It was a step in the right direction, and to be sure, the percentage of women in clinical trials has grown significantly since then.

      But participation by minorities has not increased much at all: a 2014 study found that fewer than 2 percent of more than 10,000 cancer clinical trials funded by the National Cancer Institute focused on a racial or ethnic minority. And even if the other trials fulfilled those goals, the 1993 law regulates only studies funded by the NIH, which represent a mere 6 percent of all clinical trials.

      The shortfall is especially troubling when it comes to trials for diseases that particularly affect marginalized racial and ethnic groups. For example, Americans of African descent are more likely to suffer from respiratory ailments than white Americans are; however, as of 2015, only 1.9 percent of all studies of respiratory disease included minority subjects, and fewer than 5 percent of NIH-funded respiratory research included racial minorities.

      The problem is not necessarily that researchers are unwilling to diversify their studies. Members of minority groups are often reluctant to participate. Fear of discrimination by medical professionals is one reason. Another is that many ethnic and racial minorities do not have access to the specialty care centers that recruit subjects for trials. Some may also fear possible exploitation, thanks to a history of unethical medical testing in the U.S. (the infamous Tuskegee experiments, in which black men were deliberately left untreated for syphilis, are perhaps the best-known example). And some minorities simply lack the time or financial resources to participate.

      The problem is not confined to the U.S., either. A recent study of trials involving some 150,000 patients in 29 countries at five different time points over the past 21 years showed that the ethnic makeup of the trials was about 86 percent white….

Remember the Alamo! Remember Goliad!

[These excerpts are from pages 154-157 of The Eagle and the Raven/u> by James A. Michener.]

      For thirteen relentless days the Mexican troops besieged the defenders of the Alamo. Santa Anna conducted the battle under a blood-red flag to the marching tune Deguello, each symbol traditionally meaning: ‘Surrender now or you will be executed when we win.’ In the final charge through the walls of the Alamo there would be no quarter; the men inside knew that this time the often windy cry ‘Victory or Death’ meant what it said.

      Early in the morning of the thirteenth day Santa Anna’s foot soldiers, lashed forward by officers who did not care how many of their men were lost in the attack, stormed the walls, overcame the defenders, and slaughtered every man inside, American or Mexican. Jim Bowie was slain in his sick bed. Captain Travis was shot on the walls. What exactly happened to Davy Crockett would never be known—dead inside the walls or murdered later outside as a prisoner of war. But dead.

      The Texicans lost 186, the Mexicans about 600. One Texican, a grizzled French veteran of the Napoleonic wars, had fled the fort before the last fight began. Santa Anna had won a crushing victory and had been remorseless in exterminating Texicans.

      Any evaluation of Mexico’s stunning victory at the Alamo must consider two hideous acts of Santa Anna, acts so contemptuous of the customary decencies which always existed between honorable adversaries that they enraged the Americans, kindling fires of revenge that would be extinguished only in the equally horrible acts that followed the great Tejas victory at San Jacinto. When a group of prisoners was brought to Santa Anna he said scornfully: ‘I do not want to see those men living’ and despite the rules which ensured safety to soldiers who surrendered honorably, he growled: ‘Shoot them,’ and they were executed.

      Enraging the Texicans even more was his treatment of the bodies of the men who had died bravely trying to defend the Alamo. Instead of providing the bodies with a decent burial, or turning them over to their friends for proper burial, he had the corpses thrown into a great pile, as if they were useless timbers, then cremated in slow fires for two and a half days. When the heat subsided, scavenging citizens probed the ashes for metal items of value, after which the bones were left to dogs and vultures. When news of the desecration circulated, a fearful oath was sworn by Texicans: ‘Remember the Alamo!’

      Flushed by his triumph, Santa Anna behaved as if he were all-powerful. When a detachment of his army won a second victory at Goliad, some miles southeast of San Antonio, taking more than four hundred prisoners during several skirmishes, he ordered the general in charge to execute every man….

      On a bright spring morning, the Mexicans marched nearly four hundred unarmed prisoners in three different groups along country roads, suddenly turning on them and murdering three hundred and forty-two. Those who escaped by fleeing across fields, ducking into woods, and throwing themselves into streams in which they swam to safety, spread news of the massacre. Across Texas men whispered with a terrifying lust for vengeance: ‘Remember the Alamo! Remember Goliad!’

How Islands Shrink People

[These excerpts are from an article by Ann Gibbons in the August 3, 2018, issue of Science.]

      Living on an island can have strange effects. On Cyprus, hippos dwindled to the size of sea lions. On Flores in Indonesia, extinct elephants weighed no more than a large hog, but rats grew as big as cats. All are examples of the so-called island effect, which holds that when food and predators are scarce, big animals shrink and little ones grow. But no one was sure whether the same rule explains the most famous example of dwarfing on Flores, the odd extinct hominin called the hobbit, which lived 60,000 to 100,000 years ago and stood about a meter tall.

      Now, genetic evidence from modern pygmies on Flores—who are unrelated to the hobbit—confirms that humans, too, are subject to so-called island dwarfing….Flores pygmies differ from their closest relatives on New Guinea and in East Asia in carrying more gene variants that promote short stature. The genetic differences testify to recent evolution—the island rule at work. And they imply that the same force gave the hobbit its short stature….

      The team found no trace of archaic DNA that could be from the hobbit. Instead, the pygmies were most closely related to other East Asians. The DNA suggested that their ancestors came to Flores in several waves: in the past 50,000 years or so, when modern humans first reached Melanesia; and in the past 5000 years, when settlers came from both East Asia and New Guinea.

      The pygmies’ genomes also reflect an environmental shift. They carry an ancient version of a gene that encodes enzymes to break down fatty acids in meat and seafood. It suggests their ancestors underwent a “big shift in diet” after reaching Flores, perhaps eating pygmy elephants or marine foods…

      The discovery fits with a recent study suggesting evolution also favored short stature in people on the Andaman Islands….Such selection on islands boosts the theory that the hobbit, too, was once a taller species, who dwindled in height over millennia on Flores.

Did Kindness Prime Our Species for Language?

[These excerpts are from an article by Michael Erard and Catherine Matacie in the August 3, 2018, issue of Science.]

      The idea is rooted in a much older one: that humans tamed themselves. This self-domestication hypothesis, which got its start with Charles Darwin, says that when early humans started to prefer cooperative friends and mates to aggressive ones, they essentially domesticated themselves….Along with tameness came evolutionary changes seen in other domesticated mammals—smoother brows, shorter faces, and more feminized features—thanks in part to lower levels of circulating androgens (such as testosterone) that tend to promote aggression.

      Higher levels of neurohormones such as serotonin were also part of the domestication package. Such pro-social hormones help us infer others' mental states, learn through joint attention, and even link objects and labels—all prerequisites for language….

      If early humans somehow developed their own lower-stress “domesticated” environment—perhaps as a result of easier access to food—it could have fostered more cooperation and reduced aggression….

      …In a famous experiment, Russian geneticist Dmitry Belyaev and colleagues selected for tameness among captured Siberian silver foxes starting in the 1950s. If a wild fox did not attack a human hand placed into its cage, it was bred. Over 50 generations, the foxes came to look like other domesticated species, with shorter faces, curly tails, and lighter coloring—traits that have since been linked to shifts in prenatal hormones.

      Unlike their wild counterparts, tame foxes came to understand the importance of human pointing and gazing….That ability to “mind read” is key to language. Thus, even though the foxes don’t vocalize in complex ways, they show that selection only for tameness can carry communication skills in its wake.

Nudge, not Sludge

[These excerpts are from an editorial by Richard H. Thaler in the August 3, 2018, issue of Science.]

      Helpful nudges abound—good signage, text reminders of appointments, and thoughtfully chosen default options are all nudges. For example, by automatically enrolling people into retirement savings plans from which they can easily opt out, people who always meant to join a plan but never got around to it will have more comfortable retirements.

      Yet, the same techniques for nudging can be used for less benevolent purposes. Take the enterprise of marketing goods and services. Firms may encourage buyers in order to maximize profits rather than to improve the buyers’ welfare (think of financier Bernie Madoff who defrauded thousands of investors). A common example is when firms offer a rebate to customers who buy a product, but then require them to mail in a form, a copy of the receipt, the SKU bar code on the packaging, and so forth. These companies are only offering the illusion of a rebate to the many people like me who never get around to claiming it. Because of such thick sludge, redemption rates for rebates tend to be low, yet the lure of the rebate still can stimulate sales—call it “buy bait.”

      Public sector sludge also comes in many forms. For example, in the United States, there is a program called the earned income tax credit that is intended to encourage work and transfer income to the working poor. The Internal Revenue Service has all the information necessary to make adjustments for credit claims by any eligible taxpayer who files a tax return. But instead, the rules require people to fill out a form that many eligible taxpayers fail to complete, thus depriving themselves of the subsidy that Congress intended they receive.

      Similarly, one of the most important rights of citizens is the ability to vote. Increased voter participation can be nudged by automatically registering anyone who applies for a driver’s license. But voter participation can also be decreased through sludge, as the state of Ohio has recently done, by purging from its list of eligible voters those who have not voted recently and who have not responded to a postcard prompt. Defenders of such sludge claim that it serves as a protection against voter fraud, despite the fact that people who intentionally vote illegally are rare.

      So, sludge can take two forms. It can discourage behavior that is in a person's best interest such as claiming a rebate or tax credit, and it can encourage self-defeating behavior such as investing in a deal that is too good to be true.

      Let’s continue to encourage everyone to nudge for good, but let's also urge those in both the public and private sectors to engage in sludge cleanup campaigns. Less sludge will make the world a better place.

Calculus of Probabilities

[This excerpt is from pages 216-217 of Great Ideas of Modern Mathematics: Their Nature and Use by Jagjit Singh (1959).]

      Chevalier de Mere was fond of a dice game which was played in the following way. A die was thrown four times in succession and one of the players bet that a six would appear at least once in four throws while the other bet against. Mere found that there was greater chance in favour of the first player, that is, of getting a six at least once in four throws. Tired of it, he introduced a variation. The game was now played with two dice instead of one and the betting was on the appearance or non-appearance of at least one double-six in twenty-four throws. Mere found that this time the player who bet against the appearance of a double-six won more frequently. This seemed strange, as at first sight the chance of getting at least one six in four throws should be the same as that of at least one double-six in twenty-four. Mere asked the contemporary mathematician, Fermat, to explain this paradox.

      Fermat showed that while the odds in favour of a single six in four throws were a little more than even (actually about 51:49), those favour of a double-six in twenty-four throws were a little less than even, being 49:51. In solving this paradox Fermat virtually created a new science, the Calculus of Probabilities. It was soon discovered that the new calculus could not only handle problems posed by gamblers like Mere, but it could also aid financial speculators engaged in marine insurance.

Western Machine Civilization

[These excerpts are from pages 50-52 and 64-65 of Great Ideas of Modern Mathematics: Their Nature and Use by Jagjit Singh (1959).]

      Lewis Mumford has divided the history of the Western machine civilisation during the past millennium into three successive but over-lapping and interpenetrating phases. During the first phase—the eotechnic phase—trade, which at the beginning was no more than an irregular trickle, grew to such an extent that it transformed the whole life of Western Europe. It is true that the development of trade led to a steady growth of manufacture as well, but throughout this period (which lasted till about the middle of the eighteenth century) trade on the whole dominated manufacture. Thus it was that the minds of men were occupied more with problems connected with trade, such as the evolution of safe and reliable methods of navigation, than with those of manufacture. Consequently, while the two ancient sources of power, wind and water, were developed at a steadily accelerating pace to increase manufacture, the attention of most leading scientists, particularly during the last three centuries of this phase, was directed towards the solution of navigational problems. The chief and most difficult of these was that of finding the longitude of a ship at sea. It was imperative that a solution should be found as the inability to determine longitudes led to very heavy shipping losses. Newton had tackled it, although without providing a satisfactorily practical answer. In fact, as Hessen has shown, Newton’s masterpiece, the Principia, was in part an endeavour to deal with the problems of gravity, planetary motions and the shape and size of the earth, in order to meet the demands for better navigation. It was shown that the most promising method of determining longitude from observation of heavenly bodies was provided by the moon. The theory of lunar motion, therefore, began to absorb the attention of an increasing number of distinguished mathematicians of England, France, Germany and America.

      Although more arithmetic and algebra were devoted to Lunar Theory than to any other question of astronomy or mathematical physics, a solution was not found till the middle of the eighteenth century, when successful chronometers, that could keep time on a ship in spite of pitching and rolling in rough weather, were constructed. Once the problem of longitude was solved it led to a further growth of trade, which in turn induced a corresponding increase in manufacture. A stage was now reached when the old sources of power, namely wind and water, proved too ‘weak, fickle, and irregular’ to meet the needs of a trade that had burst all previous bounds. Men began to look for new sources of power rather than new trade routes.

      This change marks the beginning of Mumford's second phase, the palaeotechnic phase, which ushered in the era of the ‘dark Satanic mills’. As manufacture began to dominate trade, the problem of discovering new prime movers became the dominant social problem of the time. It was eventually solved by the invention of the steam engine. The discovery of the power of steam—the chief palaeotechnic source of power—was not the work of ‘pure’ scientists; it was made possible by the combined efforts of a long succession of technicians, craftsmen and engineers from Porta, Rivault, Caus, Branca, Savery and Newcomen to Watt and Boulton.

      Although the power of steam to do useful work had been known since the time of Hero of Alexandria (A.D. 50), the social impetus to make it the chief prime mover was lacking before the eighteenth century. Further, a successful steam engine could not have been invented even then had it not been for the introduction by craftsmen of more precise methods of measurement in engineering design. Thus, the success of the first two engines that Watt erected at Bloomfield colliery in Staffordshire, and at John Wilkinson’s new foundry at Broseley, depended in a great measure on the accurate cylinders made by Wilkinson’s new machine tool with a limit of error not exceeding ‘the thickness of a thin six pence’ in a diameter of seventy-two inches. The importance of the introduction of new precision tools, producing parts with increasingly narrower ‘tolerances’, in revolutionising production has never been fully recognised. The transformation of the steam engine from the wasteful burner of fuel that it was at the time of Newcomen into the economical source of power that it became in the hands of Watt and his successors seventy years later, was achieved as much by the introduction of precision methods in technology as by Black’s discovery of the latent heat of steam….

      For about 150 years after Newton the study of the motion of material bodies, whether cannon balls and bullets, to meet the needs of war, or the moon and planets to meet those of navigation, closely followed the Newtonian tradition. Then as it was just about beginning to end up in high-brow pedantry it was rescued by the emergence of a new science—electricity—in much the same way as cybernetics was to rescue mathematical logic a century later.

      Though known from earliest times electricity became a quantitative science in 1819, when Oersted accidentally observed that the flow of an electric current in a wire deflected a compass needle in its neighbourhood. This was the first explicit revelation of the profound connection between electricity and magnetism, already suspected on account of a number of analogies between the two. A little later Faraday showed that this connection was no mere one-sided affair. If electricity in motion produced magnetism, then equally magnets in motion produced electricity. In other words, electricity in motion produced the same effects as stationary magnets and magnets in motion the same effects as electricity.

      This reciprocal relation between electricity and magnetism led straightway to a whole host of new inventions from the electric telegraph and telephone to the electric motor and dynamo. In fact, it is the seed from which has sprouted the whole of heavy electrical industry which was destined to transform the paleotechnic phase of Western machine civilisation with its ugly, dark and satanic mills, into the neotechnic phase based on electric power. But before this industry could arise results of two generations of experiments and prevailing ideas in different fields o physics—electricity, magnetism and light—had to be rationalised and synthesised in a mathematically coherent theory capable of experimental verification. Now the results of the mathematical theory depended for their verification on the establishment of accurate units for electricity—a task necessary before it could be commercialised for household use. The theory, thus verified, in turn formed the basis of electrical engineering--itself the result of a complete interpenetration of deductive reasoning and experimental practice. It reached the apogee of its success when Hertz experimentally demonstrated the existence of electromagnetic waves, which Maxwell had postulated on purely theoretical grounds, and from which wireless telegraphy and all that it implies was to arise later.

      Maxwell’s theory was actually a mathematisation of the earlier physical intuitions of Faraday. In this he used all the mathematical apparatus of mechanics and calculus of the Newtonian period. But in some important and puzzling respects the new laws of electromagnetism differed from those of Newton. In the first place, all the forces between bodies that he considered as, for example, the force of earth’s gravity on falling bodies, acted along the line joining their centres. But in the case of a magnetic pole it was urged to move at right angles to the line joining it to the current-carrying wire. Secondly, electromagnetic theory was differentiated from the earlier gravitation theory of Newton in its insistence that electric and magnetic energy actually resided in the surrounding empty space. According to this view the forces acting on electrified and magnetised bodies did not form the whole system of forces in action but only served to reveal the presence of a vastly more intricate system of forces acting everywhere in free space….

Cinderella and Equations

[This excerpt is from page 43 of Great Ideas of Modern Mathematics: Their Nature and Use by Jagjit Singh (1959).]

      It is needless to add that it is easier to write equations, whether differential, integral or integro-differential, than to solve them. Only a small class of such equations has been solved explicitly. In some cases, when, due to its importance in physics or elsewhere, we cannot do without an equation of the insoluble variety, we use the equation itself to define the function, just as Prince Charming used the glass slipper to define Cinderella as the girl who could wear it. Very often the artifice works; it suffices to isolate the function from other undesirables in much the same way as the slipper sufficed to distinguish Cinderella from her ugly sisters.

An Earlier Perception of Computers Later

An Earlier Perception of Computers

      [This excerpt is from pages 24-26 of Great Ideas of Modern Mathematics: Their Nature and Use by Jagjit Singh (1959).]

      Now, as Norbert Wiener has remarked, the human and animal nervous systems, which too are capable of the work of a computation system, contain elements—the nerve cells or neurons—which are ideally suited to act as relays :

      `While they show rather complicated properties under the influence of electrical currents, in their ordinary physiological action they conform very nearly to the "all-or-none" principle; that is, they are either at rest, or when they "fire" they go through a series of changes almost independent of the nature and intensity of the stimulus.' This fact provides the link between the art of calculation and the new science of Cybernetics, recently created by Norbert Wiener and his collaborators

      This science (cybernetics) is the study of the 'mechanism of control and communication in the animal and the machine', and bids fair to inaugurate a new social revolution likely to be quite as profound as the earlier Industrial Revolution inaugurated by the invention of the steam engine. While the steam engine devalued brawn, cybernetics may well devalue brain—at least, brain of a certain sort. For the new science is already creating machines that imitate certain processes of thought and do some kinds of mental work with a speed, skill and accuracy far beyond the capacity of any living human being.

      The mechanism of control and communication between the brain and various parts of an animal is not yet clearly understood. We still do not know very much about the physical process of thinking in the animal brain, but we do know that the passage of some kind of physico-chemical impulse through the nerve-fibres between the nuclei of the nerve cells accompanies all thinking, feeling, seeing, etc. Can we reproduce these processes by artificial means? Not exactly, but it has been found possible to imitate them in a rudimentary manner by substituting wire for nerve-fibre, hardware for flesh, and electro-magnetic waves for the unknown impulse in the living nerve-fibre. For example, the process whereby flatworms exhibit negative phototropism—that is, a tendency to avoid light—has been imitated by means of a combination of photocells, a Wheatstone bridge and certain devices to give an adequate phototropic control for a little boat. No doubt it is impossible to build this apparatus on the scale of the flatworm, but this is only a particular case of the general rule that the artificial imitations of living mechanisms tend to be much more lavish in the use of space than their prototypes. But they more than make up for this extravagance by being enormously faster. For this reason, rudimentary as these artificial reproductions of cerebral processes still are, the thinking machines already produced achieve their respective purposes for which they are designed incomparably better than any human brain.

      As the study of cybernetics advances—and it must be remembered that this science is just an infant barely ten years old—there is hardly any limit to what these thinking-machines may not do for man. Already the technical means exist for producing automatic typists, stenographers, multilingual interpreters, librarians, psychopaths, traffic regulators, factory-planners, logical truth calculators, etc. For instance, if you had to plan a production schedule for your factory, you would need only to put into a machine a description of the orders to be executed, and it would do the rest. It would know how much raw material is necessary and what equipment and labour are required to produce it. It would then turn out the best possible production schedule showing who should do what and when.

      Or again, if you were a logician concerned with evaluating the logical truth of certain propositions deducible from a set of given premises, a thinking machine like the Kahn-Burkhart Logical Truth Calculator could work it out for you very much faster and with much less risk of error than any human being. Before long we may have mechanical devices capable of doing almost anything from solving equations to factory planning. Nevertheless, no machine can create more thought than is put into it in the form of the initial instructions. In this respect it is very definitely limited by a sort of conservation law, the law of conservation of thought or instruction. For none of these machines is capable of thinking anything new.

      A 'thinking machine' merely works out what has already been thought of beforehand by the designer and supplied to it in the form of instructions. In fact, it obeys these instructions as literally as the unfortunate Casabianca boy, who remained on the burning deck because his father had told him to do so. For instance, if in the course of a computation the machine requires the quotient of two numbers of which the divisor happens to be zero, it will go on, Sisyphus-wise, trying to divide by zero for ever unless expressly forbidden by prior instruction. A human computer would certainly not go on dividing by zero, whatever else he might do. The limitation imposed by the aforementioned conservation law has made it necessary to bear in mind what Hartree has called the 'machine-eye view' in designing such machines. In other words, it is necessary to think out in advance every possible contingency that might arise in. the course of the work and give the machine appropriate instructions for each case, because the machine will not deviate one whit from what the `Moving Finger’ of prior instructions has already decreed. Although the limitation imposed by this conservation law on the power of machines to produce original thinking is probably destined to remain forever, writers have never ceased to speculate on the danger to man from robot machines of his own creation. This, for example, is the moral of stories as old as those of Famutus and Frankenstein, and as recent as those of Karel Capek's play, R.U.R., Olaf Stapledon’s First and Last Men.

      It is true that as yet there is no possibility whatsoever of constructing Frankenstein monsters, Rossum robots or Great Brains—that is, artificial beings possessed of a 'free will' of their own. This, however, does not mean that the new developments in this field are without danger to mankind. The danger from the robot machines is not technical but social. It is not that they will disobey man but that if introduced on. a large enough scale, they are liable to lead to widespread unemployment.

Irrational Numbers

[This excerpt is from pages 15-16 of Great Ideas of Modern Mathematics: Their Nature and Use by Jagjit Singh (1959).]

      The discovery of magnitudes which, like the diagonal of a unit square, cannot be measured by any whole number or rational fraction, that is, by means of integers, singly or in couples, was first made by Pythagoras some 2500 years ago. This discovery was a great shock to him. For he was a number mystic who looked upon integers…as the essence and principle of all things in the universe. When, therefore, he found that the integers did not suffice to measure even the length of the diagonal of a unit square, he must have felt like a Titan cheated by the gods. He swore his followers to a secret vow never to divulge the awful discovery to the world at large and turned the Greek mind once for all away from the idea of applying numbers to measure geometrical lengths. He thus created an impassable chasm between algebra and geometry that was not bridged till the tie of Descartes nearly 2000 years later.

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