Science Friday

There are over 160,000 species of moths worldwide, and they come in all different shapes and sizes. For example, the Comet Moth, native to the rainforests of Madagascar, boasts vibrant red and yellow patterned wings, feathery antennae, and long swapping tails, thought to useful for distracting its bat predators. By comparison, most common North American moths seem boring and dull. While their butterfly relatives flit about the garden in daylight, moths are often found lurking around outside lamps at night. And they can be a nuisance—eating holes in your cashmere sweaters or natural fiber rugs. Even in popular culture they get a bad rap. We use terms like “moth-balled” to describe a cancelled project and “like a moth to flame” when we talk about a perilous situation.  But do moths deserve the unflattering characterization of the mysterious, scaly-winged insect that haunts the night? Dr. David Lees, Curator of Lepidoptera at the Natural History Museum of London, certainly doesn’t think so. He joins Ira to set the record straight about moths by highlighting their astonishing diversity and usefulness. Actor and writer Alan Alda might be best known as Hawkeye Pierce in M*A*S*H, or as a familiar face from several Woody Allen films. But he also spent more than a decade interviewing scientists on Scientific American Frontiers, and later founded a center to teach scientists how to communicate better with the public—through improv. His latest project is hosting the podcast Clear + Vivid, where he’s interviewed a long list of public figures, from Adam Driver to Melinda Gates, and a wide variety of scientists like climate scientist Katharine Hayhoe and primatologist Frans de Waal. In this interview with Ira, he focuses on a few memorable moments in the podcast that illustrate how to talk about tough topics like climate change. A cemetery isn’t necessarily the first place that comes to mind when thinking about urban biodiversity and conservation, and, for a while, even ecologists wrote them off. But there’s a growing body of research that’s come together in recent years pointing to the value of these unexpected green spaces in protecting biodiversity, especially in cities where land is at a premium and green space is limited. Researchers even discovered a new beetle species at a cemetery in Brooklyn earlier this summer and spotted a rare salamander species in the same cemetery only a few years earlier. But it’s not just beetles and salamanders that take refuge in cemeteries. Lichen, which are an algae-fungi amalgamation, do too. Jessica Allen, assistant professor of biology at Eastern Washington University and an expert in New York City lichen, joins Ira to discuss the rare lichen that her research team found in a cemetery in the Bronx and why cemeteries are helping lichen to thrive in NYC.   Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

Eighteen years ago, a lawyer named Robert Bilott sent a letter to the EPA, the attorney general, and other regulators, warning them about a chemical called PFOA, short for perfluorooctanoic acid. Outside of the companies that made and used PFOA, most people had never heard of it. But E.I. du Pont de Nemours and Company, better known as DuPont, had been using PFOA to make Teflon since the early 1950s. In the course of a lawsuit against the chemical corporation, Bilott had uncovered a trove of internal company documents, showing DuPont had been quietly monitoring the chemical’s health risks for decades, studying laboratory animals and their own workers. Bilott called on regulators to investigate and take action. PFOA has since been linked to testicular and kidney cancer, among other diseases. It is part of a larger class of perfluoroalkyl and polyfluoroalkyl substances (PFAS), which have now been detected in everything from polar bears in Svalbard to fish in South Carolina, and are estimated to be in the blood of over 98% of Americans. In the mid-2000s manufacturers started voluntarily phasing out PFOA and a related chemical, PFOS, but they substituted them with other PFAS chemicals, whose possible health effects are still being investigated and litigated. Nearly two decades after Bilott wrote the EPA, the agency has not regulated these chemicals, but it says it plans to begin the process by the end of this year. Bilott, who previously secured a $670 million settlement from DuPont, is now suing DuPont, Chemours, and others on behalf of everyone in the United States who has PFAS in their blood. This week, Robert Bilott tells Ira his story, now featured in his book, Exposure, and the movie, Dark Waters, out in theaters November 22. You can read an excerpt of Bilott’s book here. Sharon Lerner of The Intercept also joins to discuss what is known about these chemicals, and what is and isn’t being done to limit our exposure. Morgan Bengel stood about 35 feet underground, gesturing at the cold, rocky walls inside Old New-Gate Prison & Copper Mine. Late 18th-century descriptions of this subterranean penitentiary were bleak. “Some of the words are, hell, a dungeon, woeful mansion,” Bengel said. You’d think this would be the perfect place to find bats. It’s a dark damp cave. But during a bat survey here last winter scientists only found 10. That’s because of white-nose syndrome. A disease caused by a fungus, which flourishes in caves, just like this one. The fungus gets on the muzzle and wings of bats, waking them up from hibernation, and depleting the fat they need to survive the winter. It’s been more than a decade since the disease was first identified in North America. Since then, white-nose has killed off millions of bats across New England and other parts of the U.S. and Canada. “We have a site in western Connecticut that was over 3,300 bats that we documented during a winter hibernaculum survey in 2007,” said Kate Moran, a wildlife biologist with the state Department of Energy and Environmental Protection. “We returned there in 2009 and there were more like 300 bats. We returned there in 2010, and we counted fewer than a dozen bats. It was carnage, really.” White-nose was first documented in New York in the winter of 2006 to 2007. Since then, it’s spread to at least 33 states and 7 Canadian provinces, including all of New England. In Connecticut caves, DEEP biologist Brian Hess said it’s virtually everywhere. “To our knowledge, all of the caves in Connecticut have the fungal pathogen living in them,” Hess said. Across Connecticut, the numbers of cave-dwelling bats like the northern long-eared bat, little brown bat, and tri-colored bat all dropped dramatically between 2007 and 2010. Moran said they still haven’t recovered. “In New England bats were very common. The northern long-eared bat was probably the most common bat we had throughout New England. Now it is the least common bat we have in New England,” Moran said. And it’s listed as “threatened” under the Federal Endangered Species Act. Bats are beneficial to people. They eat moths and beetles that can pose dangers to crops. And they also consume mosquitoes, which can spread dangerous diseases like West Nile virus and Eastern equine encephalitis.   Bats also live a long time. Moran said up to 30 years. And bats usually only produce one pup per year, which means any recovery will take a long time. But it’s not all bad news. Hess said that while white-nose syndrome is present in all of Connecticut’s caves, there are spots within those areas where the fungus doesn’t do as well. “There are little microclimates within caves that can help bats to survive that fungal load, because the fungus doesn’t grow quite as well if it’s warmer or cooler, or more or less humid than the fungus really, really likes,” Hess said. What the fungus also doesn’t like, is going outside. It doesn’t survive in UV light or in springtime temperatures, so if a bat can make it through the winter, it can still have a shot at recovery. That means hope for both the bats and the biologists working to conserve them. “They’re still here. They haven’t blinked out,” Hess said. “When you have these introductions of diseases or pests, things are dire. But the fact that we still have bats is an encouragement and a reason to keep trying to make sure they still hang around.” Hess said next year, the plan is to come back to New-Gate, to count bats and try to learn a little bit more about the handful of winter survivors who will awaken from an ecological nightmare.   Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

When the World Wide Web was first being developed, African American software engineers, journalists and entrepreneurs were building search engines, directories, and forums to connect and bring on black web users and communities. In his book Black Software: The Internet and Racial Justice, from the AfroNet to Black Lives Matter, Charlton McIlwain tells the stories of these individuals. McIlwain also discusses the role these technologies can play in racial justice including how digital data can become segregated and the role social media platforms can play in offline social movements. Plus, mucus gets a bad rap for its “ick” factor. But without it, you couldn’t blink, swallow, smell, or taste. You couldn’t digest your food, either. In fact, you wouldn’t even exist. The slimy material is the miraculous reason for our survival. Mucus is a ubiquitous natural goo. Jellyfish and hagfish have it; corals, which spend 40% of their daily energy intake producing mucus, are coated with it; even vegetables ooze it. The substance is built from tiny thread-like polymers that look like bottle brushes, she says, and that backbone is studded with sugars called glycans. Those sugars appear to be one of the key ingredients that allows mucus to pacify problematic pathogens, according to a new study from Ribbeck’s group. The work is in the journal Nature Microbiology. In this segment, Ribbeck talks with Ira about the molecular complexities of mucus, and the many wondrous qualities of this potent and protective natural goo. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

Spiders were one of the first animals to evolve on land. And over the span of 400 million years of speciation and evolution, they’ve learned some amazing tricks. One of their trademarks? The strong, sticky substance that we call silk—every spider produces it, whether for weaving webs, wrapping prey, or even leaving trails on the ground for potential mates.  But every silk is unique, each with different chemistry and different physical properties. Even a single spider web may use multiple kinds of silk. So how did spiders develop these wondrous fibers? We hear from Cheryl Hayashi at the American Museum of Natural History, Sarah Han at the University of Akron, and Linda Rayor at Cornell University about their work.  Plus, a "dead zone" in the Gulf of Mexico has states along the Mississippi working to reduce nutrient runoff. Science and environment reporter Eli Chen from St. Louis Public Radio tells the us the State of Science. And, Google says its quantum computer has achieved in just 200 seconds what would take a supercomputer thousands of years. But IBM is pushing back. Sophie Bushwick, technology editor at Scientific American, joins Ira to talk about what this means and other stories from this week in science. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

In the 1980s and 1990s, in the midst of rising crime rates and a nationally waning confidence in policing, law enforcement around the country adopted a different approach to addressing crime. Instead of just reacting to crime when it happened, officers decided they’d try to prevent it from happening in the first place, employing things like “hot spots” policing and “stop and frisk,” or “terry stops.” The strategy is what criminologists call proactive policing, and it’s now become widely used in police departments across the nation, especially in cities. Critics and experts debate how effective these tactics are in lowering crime rates. While there’s some evidence that proactive policing does reduce crime, now public health researchers are questioning if the practice—which sometimes results in innocent people being stopped, searched, and detained—comes with other unintended physical and mental health consequences. Samuel Walker, emeritus professor of criminology at the University of Nebraska Omaha and an expert in police accountability, reviews what led police departments to adopt a more proactive approach, while medical sociologist Alyasah Ali Sewell explains the physical and mental health impacts of stop-question-and-frisk policing. If you live near the coasts, you may occasionally enjoy a good clam bake. Thousands of years ago, indigenous people in the Pacific Northwest were much the same, with clams forming an important part of the coastal diet and culture. In fact, inhabitants of the Pacific Northwest developed techniques for cultivating clams in constructed ‘clam gardens’ along the coastline. A new study published this week in the Proceedings of the National Academy of Sciences found that those clam gardens were very successful, allowing the farmed clams to sustainably grow larger and more rapidly than untended clams, despite being heavily harvested. Dana Lepofsky, a professor of archaeology at Simon Fraser University and one of the authors of that study, joins Ira to describe the technology of the clam garden and what it might be able to teach us about modern sustainable aquaculture. This week, a congressional hearing examined NASA’s plan to return humans to the moon by 2024—and some Appropriations Committee members didn’t seem particularly bullish on the idea. New York Representative José E. Serrano had this to say: Since NASA had already programmed the lunar landing mission for 2028, why does it suddenly need to speed up the clock by four years—time that is needed to carry out a successful program from a science and safety perspective. To a lot of Members, the motivation appears to be just a political one—giving President Trump a moon landing in a possible second term, should he be reelected. In this segment, Eric Berger, a senior space editor at Ars Technica, talks with Ira about the implications of that hearing. Plus, as it rushes to meet that 2024 deadline, NASA this week unveiled a new spacesuit, tailor-made for strolling on the lunar surface. Amy Ross of NASA Johnson Space Center led the suit’s design, and she joins Ira here to talk about its capabilities—and why a puffy suit is still necessary, rather than a tighter design depicted and described in films like The Martian. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

When the water rises, whether from heavy rains or rising seas, communities have a few options: reinforce flood-threatened homes, rebuild after the water recedes, or—in places where the threat of repeated floods and even more damage is increasing—leave. And while leaving may feel synonymous with defeat, more cities and states are interested in encouraging people to leave risky floodplains—a process called managed retreat. FEMA offers a buyout program that usually involves offering homeowners money to encourage them to move elsewhere. New York Times reporter Christopher Flavelle and University of Delaware social scientist A.R. Siders describe some of the different ways cities and states have attempted the process: from Staten Island residents who took buyouts after flooding from Hurricane Sandy, to Louisiana’s new statewide plan for strategically targeting high-risk areas. But how can managed retreat go wrong? New research in Science Advances from Siders and her colleagues has found that it’s often rich counties that apply for FEMA money, and they often use it for buying out poorer residents—leading to questions of whether resources or opportunities are being distributed equitably. Jola Ajibade, a geographer at Portland State University, expands these questions to the global scale: In Lagos, Nigeria, managed retreat offers no financial incentive to people being asked to leave. And in Manila, Philippines, people are offered new homes, but aren’t given a way to earn a livelihood. Finally, with enough planning, can retreating retain the fabric of an entire community? In Sidney, New York, neighbors have been waiting eight years trying to move together to higher ground—and they’re still caught up in red tape. The planned relocation of a Native American community on Isle de Jean Charles, Louisiana, has hit roadblocks as well. But small Midwestern towns fleeing massive river floods have tried the same, and seem to be thriving decades later: see Soldiers Grove, Wisconsin, and Valmeyer, Illinois. Lehigh University anthropologist David Casagrande explains why collective community planning may end up being a key factor in retreat that leaves peoples’ lives and livelihoods most intact. At a United Nations climate meeting in Poland last year, President Trump’s advisor on energy and climate change didn’t advance a forward-thinking plan to tackle climate change, but instead extolled the virtues of natural gas and even coal—one of the dirtiest fossil fuels. So, in the absence of meaningful federal policy on climate change, a grassroots effort by 435 U.S. mayors seeks to solve the climate problem, starting at the local level instead. Emily Atkin, who writes the HEATED newsletter about the climate crisis, talks about that and other climate policy stories in the news, such as the lack of climate questions at the Democratic debate and the candidates’ views on punishing fossil fuel companies; Google donations that fuel climate science denial; and the Department of Agriculture’s lack of assistance for farmers dealing with increasingly extreme weather. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

If you live and work in an urban area, you might think about the air quality outside your home or workplace. But what about the air quality inside the office? It turns out that on average, indoor environments have higher concentrations of potentially harmful substances, such as aerosols and volatile organic compounds (VOCs). While past research has focused on chemical emissions from building materials, cleaning supplies, and even furniture, air pollution researchers are increasingly looking at another source of toxic air: us. New research from Purdue University to be presented at the American Association for Aerosol Research conference has found that the majority of indoor VOCs may be released by a seemingly innocuous source: human beings, their lunches and coffee breaks, and anything they may wear or bring to work. And many of these compounds, such as the terpenes released by peeling an orange, or the squalene released in human skin oil, react with ozone to form even more worrisome molecules. If you’ve ever played the classic puzzle-like computer game Tetris, you know that it starts out slowly. As the seven different pieces (called “zoids” by the initiated) descend from the top of the screen, a player has to shift the pieces horizontally and rotate them so that they fit into a gap in the stack of pieces at the bottom of the screen, or “well.” In early levels, the pieces might take 10-15 seconds to fall. The speed increases at each level. In world champion Tetris matches, players often start play at Level 18—in which pieces are on the screen for about a second. Wayne Gray, a professor of cognitive science at Rensselaer Polytechnic University, calls it a problem of “predictive processing and predictive action.” Champion-level expert players, he says, are able to take in the state of the gameboard and react almost immediately, without going through the mental steps of figuring out how to move the piece and rotate it that a novice player requires. “They can see the problem and reach a decision at the same time,” he said. Gray and colleagues have attended the Classic World Tetris Championship tournament for three years, collecting data from expert players using a modified version of the game that collects keystrokes and eye-tracking data. He joins Ira to discuss what the researchers are learning about expert decision-making, and what he hopes to study at this year’s upcoming Tetris tournament. The pharmaceutical industry has been on a 30 year mission to develop a drug to treat Alzheimer’s disease. The culprits behind the disease, they thought, were the amyloid plaques that build up in the brains of these patients. For many decades removing these plaques to treat Alzheimer’s was the goal. But then drug after drug targeting amyloid failed to improve the symptoms of Alzheimer’s—the so-called “amyloid hypothesis” wasn’t bearing out. But drug companies kept developing and testing drugs that attacked amyloid from every angle—perhaps at the expense of pursuing other avenues of treatment. This past summer, two more high profile clinical trials of drugs to treat Alzheimer’s failed. That brings the number of successful treatments for the disease, which affects 5.8 million Americans, to zero. George Perry, professor of biology at UT San Antonio and Derek Lower, a drug researcher and pharmaceutical industry expert join Ira to explain what led pharmaceutical companies to doggedly pursue the amyloid hypothesis for decades, and whether or not they are ready to start trying something else.   Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

Despite widely reported attacks on science, the vast majority of Americans continue to trust scientists, according to the latest survey from the Pew Research Center. Many listeners of Science Friday might take it as a given that we should trust science, but is that trust well-founded? Naomi Oreskes, history of science professor at Harvard University, argues that we should. In her new book, Why Trust Science?, she explains how science works and what makes it trustworthy. (Hint: it’s not the scientific method.) Pacific Gas & Electric has generated confusion—not to mention outrage—with its power grid shutdowns. The situation continues for a second day in 34 California counties. On social media and phone calls to KQED’s Forum radio program, people throughout PG&E’s service area have asked how and why the investor-owned utility took this step. KQED reporters have some answers to some of the questions that have come in. Why Is PG&E Turning the Power Off? Is This PG&E’s Fault? Bottom line, PG&E doesn’t want to risk having its power lines start another fire, so it is pre-emptively turning the power off during this week’s dry, windy weather. The company made the decision based on information from its wildfire center, where meteorologists keep watch on fire conditions. PG&E’s power lines have sparked many catastrophic wildfires in California, including last year’s Camp Fire in Butte County that caused 85 deaths, making it the deadliest U.S. wildfire in 100 years. PG&E lines started more than a dozen fires in 2017. Less than a month ago, the company agreed to pay billion in a settlement with victims of the recent fires. The shutoffs are part of its wildfire mitigation plan, mandated by the state and agreed to by the California Public Utilities Commission, the state’s top power regulator. — Kevin Stark Who Made This Decision? When Did They Make It? If past practice tells us anything, PG&E has been making and remaking this decision, with the help of its meteorological team, over several days. The utility says it considers weather, fuel and other conditions and observations, as well as the need for notice by state and local parties, when it decides to implement shutoffs. As we’ve seen over the last few days, the planned outage times can change with shifting conditions. The fact is, there’s nothing new about turning off power lines when conditions get risky: San Diego Gas and Electric, with the permission of the CPUC, has mitigated fire risk this way since 2012. What is new are the guidelines PG&E filed just a year ago for its public safety power shutoff procedures. For the last couple of years, the CPUC has required investor-owned utilities to describe their processes for arriving at decisions like the one affecting nearly three dozen California counties right now. PG&E shut off power two times last year; the last time PG&E called a public safety power shutoff, for two days in June, it affected about 22,000 customers in the North Bay and the Sierra foothills, including Butte County and Paradise. — Molly Peterson Read more questions and answers on Science Friday. Cartilage is the connective tissue that provides padding between your joints. As we age, the wearing down of cartilage can lead to different types of arthritis. It’s been long believed that once humans lose cartilage, it can never grow back. Now, a team of researchers investigated this idea, and found that the cartilage in our ankles might be able to turnover more easily compared to our hips and knees. Their results were published in the journal Science Advances. Rheumatologist Virginia Byers Kraus, who was an author on the study, discusses how human cartilage might be able to regenerate and what this means for future treatments.       Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

Flour, salt, yeast and water are the basic ingredients in bread that can be transformed into a crusty baguette or a pillowy naan. But what happens when you get a sticky sourdough or brick-like brioche? Chef Francisco Migoya of Modernist Cuisine breaks down the science behind the perfect loaf. He talks about how gluten-free flours affect bread structure, the effects of altitude and humidity on dough and how to keep your sourdough starter happy. Plus, amateur baker and “Father of the Xbox” Seamus Blackley describes how he baked a loaf of bread from an ancient Egyptian yeast. The Bureau of Land Management issued an environmental impact statement last month that examines the effects that oil development will have on the Arctic National Wildlife Refuge. Buried deep in the appendix of the report was this BLM response to a public comment: "The BLM does not agree that the proposed development is inconsistent with maintaining a livable planet (i.e., there is not a climate crisis). The planet was much warmer within the past 1,000 years, prior to the Little Ice Age, based on extensive archaeological evidence (such as farming in Greenland and vineyards in England). This warmth did not make the planet unlivable; rather, it was a time when societies prospered." The comment alludes to the so-called “Medieval Warm Period,” which is commonly referenced by climate change deniers to justify their beliefs. The BLM has since said the comment had no bearing on the scientific conclusions contained elsewhere in the report. Adam Aton, a climate reporter at E&E News, joins Ira to talk about the report, and what fossil fuel development in the Arctic might mean for local wildlife and the planet. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

Today, it’s much easier to find smart TVs on the market. Companies like Vizio and Samsung create devices capable of internet connection and with built-in apps that let you quickly access your favorite streaming services. But that convenience comes with a hidden cost—one you pay for with your data.  Smart TVs have joined the list of internet connected devices looking to harvest your data. They can track what shows you watch, then use that data to deliver targeted ads, just like Facebook. Not worried about what media companies know about your binge watching habits? New research suggests that’s not everything smart TVs are doing. If you are the owner of just one of many “internet of things” devices in your home, those devices could be talking to each other, influencing what gets advertised to you on your phone, tablet, and TV screen. Dave Choffnes, associate professor of computer science at Northeastern University, and Nick Feamster, director of the Center for Data and Computing at the University of Chicago, join Ira to share what they each found when they looked into the spying habits of your smart devices. Cooking food changes it in fundamental ways. Cooked starches are easier to digest. Seared meats are less likely to give us foodborne pathogens. And overall, we get more energy out of cooked foods than raw. But scientists are still pursuing a pivotal question about cooking: How did its invention change our bodies and shape our evolution? Did it shrink our teeth and digestive tracts? Or did it increase our brain size? Researchers writing in Nature Microbiology reported a new chapter in our understanding of how cooking has changed us: The microbial communities in our guts change dramatically if our food is cooked or raw. And mice whose microbiomes were associated with raw foods seem to gain weight more easily—but their microbiomes also showed signs of damage from plant-generated antimicrobial chemicals. Harvard researcher Rachel Carmody explains the findings, and what our microbiomes might say about cooking food and evolution. Between water and electricity, Colorado’s legal cannabis industry already has a big environmental footprint. But what about Front Range air quality? Could the plant itself be contributing to air pollution? No, it’s not the pot smoke. Colorado Department of Public Health and Environment is conducting a study of terpenes, the organic compounds that make the cannabis plant smell so strong. Terpenes are classified as volatile organic compounds. Many consumer products release VOCs, like acetone in nail polish remover and butanal from barbecues and stoves. VOCs from terpenes are harmless until they combine with combustion gases to create ozone. That’s why the state is studying marijuana emissions—it’s about where it’s grown. Unlike other VOC-emitting crops, like lavender, cannabis is often cultivated in greenhouses in the industrial areas of cities, near highways and lots of cars. “Here in Colorado, as far as air quality concerns go, ozone is our largest pollutant of concern. We are not meeting the national ambient air quality standards for ozone,” said CDPHE’s lead researcher on this project, Kaitlin Urso. Denver’s ozone problem is especially bad. According to the American Lung Association, it has the nation’s 12th worst air quality. Usually, it’s the Environmental Protection Agency that studies emissions from new industries. Since marijuana is still a federally controlled substance, it can’t. With the feds on the sideline, Urso said it’s now up to the state to figure out, essentially, “how many pounds of VOCs are emitted into our atmosphere per pound of marijuana grown?”   Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.