The abominable snowman, the yeti, bigfoot, and sasquatch—these long-lived myths of giant, hairy hominids depend on dropping elusive clues to stay in the popular imagination—a blurry photo here, a big footprint there—but what happens when scientists try to pin that evidence down? Online News Editor David Grimm talks with Sarah Crespi about the latest attempts to verify the yeti’s existence using DNA analysis of bones and hair and how this research has led to more than the debunking of a mythic creature. Sarah also interviews Alison Macintosh of the University of Cambridge in the United Kingdom about her investigation of bone, muscle, and behavior in prehistory female farmers—what can a new database of modern women’s bones—athletes and regular folks—tell us about the labor of women as humans took up farming?   Listen to previous podcasts. [Image: Didier Descouens/CC BY SA 3.0; Music: Jeffrey Cook]

This week, three papers came out describing new approaches to folding DNA into large complex shapes—20 times bigger than previous DNA sculptures. Staff Writer Bob Service talks with Sarah Crespi about building microscopic teddy bears, doughnuts, and more from genetic material, and using these techniques to push forward fields from materials science to drug delivery. Sarah also interviews Philip Cook of Duke University in Durham, North Carolina, about his Policy Forum on gun regulation research. It’s long been hard to collect data on gun violence in the United States, and Cook talks about how some researchers are getting funding and hard data. He also discusses some strong early results on open-carry laws and links between gun control and intimate partner homicide. Listen to previous podcasts. [Image: : K. WAGENBAUER ET AL., NATURE, VOL. 551, 2017; Music: Jeffrey Cook]

Whales and dolphins have incredibly sensitive hearing and are known to be harmed by loud underwater noises. David Grimm talks with Sarah Crespi about new research on captive cetaceans suggesting that some species can naturally muffle such sounds—perhaps opening a way to protect these marine mammals in the wild. Sarah also interviews Staff Writer Jeffrey Mervis about his story on the future of autonomous cars. Will they really reduce traffic and make our lives easier? What does the science say?    Listen to previous podcasts.    [Image: Laura Wolf/Flickr; Music: Jeffrey Cook]

Dave Grimm—online news editor for Science—talks with Sarah Crespi about a few of this year’s top stories from our online news site, like ones on a major error in the monarch butterfly biological record and using massive balloons to build tunnels, and why they were chosen. Hint: It’s not just the stats. Sarah also interviews Staff Writer Adrian Cho about the 2017 Breakthrough of the Year. Adrian talks about why Science gave the nod to the Laser Interferometer Gravitational-Wave Observatory team for a second year in a row—for the detection of a pair of merging neutron stars. Jen Golbeck is also back for the last book review segment of the year. She talks with Sarah about her first year on the show, her favorite books, what we should have covered, and some suggestions for books as gifts. Listen to previous podcasts. [Image: f99aq8ove/Flickr; Music: Jeffrey Cook]

David Grimm—online news editor for Science—talks with Sarah Crespi about a long-term project monitoring raccoon latrines in California. What influence do these wild bathrooms have on the ecosystem? Sarah also interviews Christian Jobin of the University of Florida in Gainesville about his Perspective on three papers linking the success of cancer immunotherapy with microbes in the gut—it turns out which bacteria live in a cancer patient’s intestines can predict their response to this cutting-edge cancer treatment. Read the related papers: Routy et al., Gut microbiome influences efficacy of PD-1–based immunotherapy against epithelial tumors, Science 2018 Gopalakrishnan et al., Gut microbiome modulates response to anti–PD-1 immunotherapy in melanoma patients, Science 2018 Matson et al., The commensal microbiome is associated with anti–PD-1 efficacy in metastatic melanoma patients, Science 2018 aan4236 Listen to previous podcasts. [Image: cuatrok77/Flickr; Music: Jeffrey Cook]

David Grimm—online news editor for Science—talks with Sarah Crespi about two underwater finds: the first sharks shown to survive off of seagrass and what fossilized barnacles reveal about ancient whale migrations. Sarah also interviews Staff Writer Adrian Cho about what happens after quantum computing achieves quantum supremacy—the threshold where a quantum computer’s abilities outstrip nonquantum machines. Just how useful will these machines be and what kinds of scientific problems might they tackle? Listen to previous podcasts.  [Image: Aleria Jensen, NOAA/NMFS/AKFSC; Music: Jeffrey Cook]

Freelance science writer Michael Price talks with Sarah Crespi about recently revealed deliberations for a coveted mathematics prize: the Fields Medal. Unearthed letters suggest early award committees favored promise and youth over star power. Sarah also interviews Julia Dressel about her Science Advances paper on predicting recidivism—the likelihood that a criminal defendant will commit another crime. It turns out computers aren’t better than people at these types of predictions, in fact—both are correct only about 65% of the time.   Jen Golbeck interviews Paul Shapiro about his book, Clean Meat: How Growing Meat Without Animals Will Revolutionize Dinner and the World, in our monthly books segment.   Listen to previous podcasts. [Image: Greg Chiasson/Flickr; Music: Jeffrey Cook]

Catherine Matacic—online news editor for Science—talks with Sarah Crespi about how geoengineering could reduce the harshest impacts of climate change, but make them even worse if it were ever turned off. Sarah also interviews Augustine Kong of the Big Data Institute at the University of Oxford in the United Kingdom about his Science paper on the role of noninherited “nurturing genes.” For example, educational attainment has a genetic component that may or may not be inherited. But having a parent with a predisposition for attainment still influences the child—even if those genes aren’t passed down. This shift to thinking about other people (and their genes) as the environment we live in complicates the age-old debate on nature versus nurture. Listen to previous podcasts. [Image: Collection of Dr. Pablo Clemente-Colon, Chief Scientist National Ice Center; Music: Jeffrey Cook]

David Grimm—online news editor for Science—talks with Sarah Crespi about the chance a naked mole rat could die at any one moment. Surprisingly, the probability a naked mole rat will die does not go up as it gets older. Researchers are looking at the biology of these fascinating animals for clues to their seeming lack of aging. Sarah also interviews freelancer Douglas Starr about his feature story on the Dunedin Multidisciplinary Health and Development Study—a comprehensive study of the lives of all the babies born in 1 year in a New Zealand hospital. Starr talks about the many insights that have come out of this work—including new understandings of criminality, drug addiction, and mental illness—and the research to be done in the future as the 1000-person cohort begins to enter its fifth decade. Listen to previous podcasts. [Image: Tim Evanson/Flickr/CC BY-SA 2.0; Music: Jeffrey Cook]

Would happy lab animals—rats, mice, even zebrafish—make for better experiments? David Grimm—online news editor for Science—talks with Sarah Crespi about the potential of treating lab animals more like us and making them more useful for science at the same time. Sarah also interviews Jon Abbatt of the University of Toronto in Canada about indoor chemistry. What is going on in the air inside buildings—how different is it from the outside? Researchers are bringing together the tools of outdoor chemistry and building sciences to understand what is happening in the air and on surfaces inside—where some of us spend 90% of our time. Listen to previous podcasts. [Image: Austin Thomason/Michigan Photography; Music: Jeffrey Cook]

Some of our genes come alive after we die. David Grimm—online news editor for Science—talks with Sarah Crespi about which genes are active after death and what we can learn about time of death by looking at patterns of postmortem gene expression. Sarah also interviews David Merritt Johns of Columbia University about the so-called sugar conspiracy. Historical evidence suggests, despite recent media reports, it is unlikely that “big sugar” influenced U.S. nutrition policy and led to the low-fat diet fad of the ’80s and ’90s. Listen to previous podcasts. [Image: Lauri Andler (Phantom); Music: Jeffrey Cook]

We talk about the techniques of painting sleuths, how to combat alternative facts or “fake news,” and using audio signposts to keep birds from flying into buildings. For this segment, David Grimm—online news editor for Science—talks with host Sarah Crespi as part of a live podcast event from the AAAS Annual Meeting in Austin. Sarah also interviews Science News Editor Tim Appenzeller about Neandertal art. The unexpected age of some European cave paintings is causing experts to rethink the mental capabilities of our extinct cousins. For the monthly books segment, Jen Golbeck interviews with William Glassley about his book, A Wilder Time: Notes from a Geologist at the Edge of the Greenland Ice. Listen to previous podcasts. [Image: Marcus Trienke/Flickr; Music: Jeffrey Cook]

For some time after the big bang there were no stars. Researchers are now looking at cosmic dawn—the time when stars first popped into being—and are seeing hints of dark matter’s influence on supercold hydrogen clouds. News Writer Adrian Cho talks with Sarah Crespi about how this observation was made and what it means for our understanding of dark matter. Sarah also interviews Joanna Kaplanis of the Wellcome Sanger Institute in Hinxton, U.K., about constructing enormous family trees based on an online social genealogy platform. What can we learn from the biggest family tree ever built—with 13 million members spanning 11 generations? In a bonus segment recording during a live podcasting event at the AAAS Annual Meeting in Austin, Sarah talks with Michael Varnum of Arizona State University in Tempe about what people think they will do if humanity comes into contact with aliens that just happen to be microbes. Live recordings sessions at the AAAS meeting were supported by funds from the European Commission. This week’s episode was edited by Podigy. Listen to previous podcasts. [Image: Kilo-Degree Survey Collaboration/H. Hildebrandt & B. Giblin/ESO; Music: Jeffrey Cook]  

Did people domesticate animals? Or did they domesticate themselves? Online News Editor David Grimm talks with Sarah Crespi about a recent study that looked at self-domesticating mice. If they could go it alone, could cats or dogs have done the same in the distant past? Next, Sinan Aral of the Massachusetts Institute of Technology in Cambridge joins Sarah to discuss his work on true and false rumor cascades across all of Twitter, since its inception. He finds that false news travels further, deeper, and faster than true news, regardless of the source of the tweet, the kind of news it was, or whether bots were involved. In a bonus segment recording during a live podcasting event at the AAAS Annual Meeting in Austin, Sarah first speaks with Ben Munson of the University of Minnesota in Minneapolis about markers of gender and sexual orientation in spoken language and then Adrienne Hancock of The George Washington University in Washington, D.C., talks about using what we know about gender and communication to help transgender women change their speech and communication style. Live recordings sessions at the AAAS meeting were supported by funds from the European Commission. This week’s episode was edited by Podigy. Listen to previous podcasts. [Image: Rudolf Jakkel (CC0); Music: Jeffrey Cook]

When Indonesia’s Mount Toba blew its top some 74,000 years ago, an apocalyptic scenario ensued: Tons of ash and debris entered the atmosphere, coating the planet in ash for 2 weeks straight and sending global temperatures plummeting. Despite the worldwide destruction, humans survived. Sarah Crespi talks with Online News Editor Catherine Matacic about how life after Toba was even possible—were humans decimated, or did they rally in the face of a suddenly extra hostile planet? Next, Julia Buck of the University of California, Santa Barbara, joins Sarah to discuss her Science commentary piece on landscapes of disgust. You may have heard of a landscape of fear—how a predator can influence an ecosystem not just by eating its prey, but also by introducing fear into the system, changing the behavior of many organisms. Buck and colleagues write about how disgust can operate in a similar way: Animals protect themselves from parasites and infection by avoiding disgusting things such as dead animals of the same species or those with disease. This week’s episode was edited by Podigy. Listen to previous podcasts. [Image: Emma Forsber/Flickr; Music: Jeffrey Cook]

Researchers are converging on which genes are linked to morning sickness—the nausea and vomiting associated with pregnancy—and the more severe form: hyperemesis gravidarum (HG). And once we know what those genes are—can we help pregnant women feel better? News intern Roni Dengler joins Sarah Crespi to talk about a new study that suggests a protein already flagged for its role in cancer-related nausea may also be behind HG. In a second segment, Tracy Bedrosian of the Neurotechnology Innovations Translator talks about how the amount of time spent being licked by mom might be linked to changes in the genetic code of hippocampal neurons in mice pups. Could these types of genomic changes be a new type of plasticity in the brain? This week’s episode was edited by Podigy. Listen to previous podcasts. [Image: Jacob Bøtter/Flickr; Music: Jeffrey Cook]

Two of the world’s most famous research chimpanzees have finally retired. Hercules and Leo arrived at a chimp sanctuary in Georgia last week. Sarah Crespi checks in with Online News Editor David Grimm on the increasing momentum for research chimp retirement since the primates were labeled endangered species in 2015. Sarah also interviews freelancer Sophia Chen about her piece on x-ray ghost imaging—a technique that may lead to safer medical imaging done with cheap, single-pixel cameras. David Malakoff joins Sarah to talk about the big boost in U.S. science funding signed into law over the weekend. Finally, Jen Golbeck interviews author Stephanie Elizabeth Mohr on her book First in Fly: Drosophila Research and Biological Discovery for our monthly books segment. This week’s episode was edited by Podigy. Listen to previous podcasts. [Image: Crystal Alba/Project Chimps; Music: Jeffrey Cook]

A millennium ago, Viking navigators may have used crystals known as “sunstones” to navigate between Norway and Greenland. Sarah Crespi talks with Online News Editor David Grimm about how one might use a crystal to figure out where they are. Sarah also interviews freelancer Danna Staaf about her piece on sedating cephalopods. Until recently, researchers working with octopuses and squids faced the dilemma of not knowing whether the animals were truly sedated or whether only their ability to respond had been suppressed. This week’s episode was edited by Podigy. Listen to previous podcasts. [Image:  Nicholas Roerich, Guests from Overseas; Music: Jeffrey Cook]   

Geneticists and anthropologists studying historical records and modern-day genomes are finding traces of previously unknown migrants to Latin America in the 16th and 17th centuries, when Asians, Africans, and Europeans first met indigenous Latin Americans. Sarah Crespi talks with contributing correspondent Lizzie Wade about what she learned on the topic at the American Association of Physical Anthropologists’s annual meeting in Austin. Sarah also interviews Kang-Keun Ni about her research using optical tweezers to bring two atoms—one cesium and one sodium—together into a single molecule. Such precise control of molecule formation is allowing new observations of these basic processes and is opening the door to creating new molecules for quantum computing. This week’s episode was edited by Podigy. Listen to previous podcasts. [Image: Juan Fernando Ibarra; Music: Jeffrey Cook] 

Armed with new data, archaeologists are revealing that mind-altering drugs were present at the dawn of the first complex societies some 5000 years ago in the ancient Middle East. Contributing writer Andrew Lawler joins Sarah Crespi to discuss the evidence for these drugs and how they might have impacted early societies and beliefs. Sarah also interviews Sarah Hobbie of the University of Minnesota about the fate of plants under climate change. Will all that extra carbon dioxide in the air be good for certain types of flora? A 20-year long study published this week in Science suggests theoretical predictions have been off the mark. This week’s episode was edited by Podigy. Listen to previous podcasts. [Image: Public domain Music: Jeffrey Cook]

Researchers have found new clues to how the “talking drums” of one Amazonian tribe convey their messages. Sarah Crespi talks with Online News Editor Catherine Matacic about the role of tone and rhythm in this form of communication. Getting poked with a needle will probably get you moving. Apparently, it also gets charges moving in certain semiconductive materials. Sarah interviews Marin Alexe of The University of Warwick in Coventry, U.K., about this newfound flexo-photovoltaic effect. Alexe’s group found that prodding or denting certain semiconductors with tiny needles causes them to suddenly produce current in response to light. That discovery could enhance the efficiency of current of solar cell technologies. Finally, in our books segment, Jen Golbeck interviews Lucy Cooke about her new book The Truth About Animals: Stoned Sloths, Lovelorn Hippos, and Other Tales from the Wild Side of Wildlife. This week’s episode was edited by Podigy. Listen to previous podcasts. [Image: Adam Levine/Flickr; Music: Jeffrey Cook]

To study the biological differences brought on by space travel, NASA sent one twin into space and kept another on Earth in 2015. Now, researchers from that project are trying to replicate that work planet-side to see whether the differences in gene expression were due to extreme stress or were specific to being in space. Sarah Crespi talks with Online News Editor Catherine Matacic about a “control” study using what might be a comparably stressful experience here on Earth: climbing Mount Everest. Catherine also shares a recent study that confirmed what one reddit user posted 5 years ago: A single path stretching from southern Pakistan to northeastern Russia will take you on the longest straight-line journey on Earth, via the ocean. Finally, Sarah talks with Roland Kröger of the University of York in the United Kingdom about his group’s study published this week in Science. Using a combination of techniques usually reserved for materials science, the group explored the nanoscale arrangement of mineral in bone, looking for an explanation of the tissue’s contradictory combination of toughness and hardness. This week’s episode was edited by Podigy. Listen to previous podcasts. [Image: Human bone (20X) by Berkshire Community College Bioscience Image Library; Music: Jeffrey Cook]

Who were the first horse tamers? Online News Editor Catherine Matacic talks to Sarah Crespi about a new study that brings genomics to bear on the question. The hunt for the original equine domesticators has focused on Bronze Age people living on the Eurasian steppe. Now, an ancient DNA analysis bolsters the idea that a small group of hunter-gatherers, called the Botai, were likely the first to harness horses, not the famous Yamnaya pastoralists often thought to be the originators of the Indo-European language family. Sarah also talks with News Intern Katie Langin about her feature story on a single salmon gene that may separate spring- and fall-run salmon. Conservationists, regulators, and citizens are fiercely debating the role such a small bit of DNA plays in defining distinct populations. Is the spring run distinct enough to warrant protection? This week’s episode was edited by Podigy. Listen to previous podcasts. [Image: Jessica Piispanen/USFWS; Music: Jeffrey Cook] 

Two thousand years ago, ancient Romans were pumping lead into the air as they smelted ores to make the silvery coin of the realm. Online News Editor David Grimm talks to Sarah Crespi about how the pollution of ice in Greenland from this process provides a detailed 1900-year record of Roman history. This week is also resistance week at Science—where researchers explore the global challenges of antibiotic resistance, pesticide resistance, herbicide resistance, and fungicide resistance. Sarah talks with Sarah Gurr of the University of Exeter in the United Kingdom about her group’s work on the spread of antifungal resistance and what it means for crops and in the clinic. And in a bonus books segment, staff writer Jennifer Couzin-Frankel talks about medicine and fraud in her review of Bad Blood: Secrets and Lies in a Silicon Valley Startup by John Carreyrou. This week’s episode was edited by Podigy. Listen to previous podcasts. [Image: Wheat rust/Oregon State University; Music: Jeffrey Cook]

DNA fingerprinting has been used to link people to crimes for decades, by matching DNA from a crime scene to DNA extracted from a suspect. Now, investigators are using other parts of the genome—such as markers for hair and eye color—to help rule people in and out as suspects. Staff Writer Gretchen Vogel talks with Sarah Crespi about whether science supports this approach and how different countries are dealing with this new type of evidence. Sarah also talks with Jill Fernandes of the University of Queensland in Brisbane, Australia, about her Science Advances paper on a light-based technique for detecting Zika in mosquitoes. Instead of grinding up the bug and extracting Zika DNA, her group shines near-infrared light through the body. Mosquitoes carrying Zika transmit this light differently from uninfected ones. If it’s successful in larger trials, this technique could make large-scale surveillance of infected mosquitoes quicker and less expensive. In our monthly books segment, Jen Golbeck talks with author Sarah-Jayne Blakemore about her new work: Inventing Ourselves: The Secret Life of the Teenage Brain. You can check out more book reviews and share your thoughts on the Books et al. blog. This week’s episode was edited by Podigy. Listen to previous podcasts. [Image: National Institute of Allergy and Infectious Diseases, National Institutes of Health; Music: Jeffrey Cook]

Astronomers have been able to detect supermassive black holes and teeny-weeny black holes but the midsize ones have been elusive. Now, researchers have scanned through archives looking for middle-size galaxies and found traces of these missing middlers. Host Sarah Crespi and Staff Writer Daniel Clery discuss why they were so hard to find in the first place, and what it means for our understanding of black hole formation. Farming animals and plants for human consumption is a massive operation with a big effect on the planet. A new research project that calculated the environmental impact of global food production shows highly variable results for different foods—and for the same foods grown in different locations. Sarah talks with one of the researchers—Joseph Poore of the University of Oxford in the United Kingdom—about how understanding this diversity can help cut down food production’s environmental footprint and help consumers make better choices. This week’s episode was edited by Podigy. Listen to previous podcasts. [Image: Miltos Gikas/Flickr; Music: Jeffrey Cook]

What book are you taking to the beach or the field this summer? Science’s books editor Valerie Thompson and host Sarah Crespi discuss a selection of science books that will have you catching comets and swimming with the fishes. Sarah also talks with Mira Moufarrej of Stanford University in Palo Alto, California, about her team’s work on a new blood test that analyzes RNA from maternal blood to determine the gestational age of a fetus. This new approach may also help predict the risk of preterm birth. This week’s episode was edited by Podigy. Listen to previous podcasts. [Image: William Warby/Flickr; Music: Jeffrey Cook]

Nigeria, Russia, and Florida seem like an odd set, but they all have one thing in common: growing caseloads of HIV. Science Staff Writer Jon Cohen joins host Sarah Crespi to talk about this week’s big read on how the fight against HIV/AIDS is evolving in these diverse locations. Sarah also talks with Armin Raznahan of the National Institute of Mental Health in Bethesda, Maryland, about his group’s work measuring which parts of the human brain are bigger in bigger brains. Adult human brains can vary as much as two times in size—and until now this expansion was thought to be evenly distributed. However, the team found that highly integrative regions are overrepresented in bigger brains, whereas regions related to processing incoming sensory information such as sight and sound tend to be underrepresented.  This week’s episode was edited by Podigy. Listen to previous podcasts. [Image: Misha Friedman; Music: Jeffrey Cook]

Since the 2016 reports of a mysterious assault on U.S. embassy staff in Cuba, researchers have struggled to find evidence of injury or weapon. Now, new research has discovered inner-ear damage in some of the personnel complaining of symptoms. Former International News Editor Rich Stone talks to host Sarah Crespi about the case, including new reports of a similar incident in China, and what kind of weapon—if any—might have been involved. Sarah also talks with Staff Writer Gretchen Vogel about the bones of an extinct gibbon found in a 2200- to 2300-year-old tomb in China. Although gibbons were often featured in historical poetry and paintings, these bones confirm their presence and the fact that they were distinct from today’s species.   Read the research. This week’s episode was edited by Podigy. Listen to previous podcasts. [Image: Pedro Szekely; Music: Jeffrey Cook] 

Public opinion on the morality of animal research is on the downswing in the United States. But some researchers think letting the public know more about how animals are used in experiments might turn things around. Online News Editor David Grimm joins Sarah Crespi to talk about these efforts. Sarah also talks Ken Wachter of the University of California, Berkeley about his group’s careful analysis of data from all living Italians born 105 or more years before the study. It turns out the risk of dying does not continue to accelerate with age, but actually plateaus around the age of 105. What does this mean for attempts to increase human lifespan? In this month’s book segment, Jen Golbeck talks with Simon Winchester about his book The Perfectionists: How Precision Engineers Created the Modern World. Read more book reviews at our books blog, Books et al. This week’s episode was edited by Podigy. Listen to previous podcasts. [Image: Chris Jones/Flickr; Music: Jeffrey Cook]

Wild polio has been hunted to near extinction in a decades-old global eradication program. Now, a vaccine-derived outbreak in the Democratic Republic of the Congo (DRC) is threatening to seriously extend the polio eradication endgame. Deputy News Editor Leslie Roberts joins host Sarah Crespi to talk about the tough choices experts face in the fight against this disease in the DRC. Sarah also talks with Online News Editor David Grimm about when dogs first came to the Americas. New DNA and archaeological evidence suggest these pups did not arise from North American wolves but came over thousands of years after the first people did. Now that we know where they came from, the question is: Where did they go? Read the research. This week’s episode was edited by Podigy. Download a transcript of this episode (PDF) Listen to previous podcasts. About the Science Podcast [Image: Polio virus/David Goodsell/RCSB PDB; Music: Jeffrey Cook]

A detection of a single neutrino at the 1-square-kilometer IceCube detector in Antarctica may signal the beginning of “neutrino astronomy.” The neutral, almost massless particle left its trail of debris in the ice last September, and its source was picked out of the sky by the Fermi Gamma-ray Space Telescope soon thereafter. Science News Writer Daniel Clery joins host Sarah Crespi to discuss the blazar fingered as the source and how neutrinos from this gigantic matter-gobbling black hole could help astronomers learn more about mysterious high-energy cosmic rays that occasionally shriek toward Earth. Read the research. Sarah also talks with Cornell University’s Susan McCouch about her team’s work on deep-water rice. Rice can survive flooding by fast internodal growth—basically a quick growth spurt that raises its leaves above water. But this growth only occurs in prolonged, deep flooding. How do these plants know they are submerged and how much to grow? Sarah and Susan discuss the mechanisms involved and where they originated. This week’s episode was edited by Podigy. Download a transcript of this episode (PDF) Listen to previous podcasts. [Image: NASA/Goddard Space Flight Center Conceptual Image Lab; Music: Jeffrey Cook]

Suckling mothers milk is a pretty basic feature of being a mammal. Humans do it. Possums do it. But monotremes such as the platypus and echidna—although still mammals—gave up suckling long ago. Instead, they lap at milky patches on their mothers’ skin to get early sustenance. Science News Writer Gretchen Vogel talks with host Sarah Crespi about the newest suckling science—it turns out monotremes probably had suckling ancestors, but gave it up for the ability to grind up tasty, hard-shelled, river-dwelling creatures. Sarah also talks with Sandra Yuter of North Carolina State University in Raleigh about her work on fast-clearing clouds off the southwest coast of Africa. These immense marine layers appear to be exiting the coastal regions under the influence of gravity waves (not to be confused with gravitational waves). This finding can help scientists better model cloud behavior, particularly with respect to their influence on global temperatures. This week’s episode was edited by Podigy. Download a transcript of this episode (PDF) Listen to previous podcasts. [Image: North Carolina State University]    

Billions of years ago, Mars probably hosted many water features: streams, rivers, gullies, etc. But until recently, water detected on the Red Planet was either locked up in ice or flitting about as a gas in the atmosphere. Now, researchers analyzing radar data from the Mars Express mission have found evidence for an enormous salty lake under the southern polar ice cap of Mars. Daniel Clery joins host Sarah Crespi to discuss how the water was found and how it can still be liquid—despite temperatures and pressures typically inhospitable to water in its liquid form. Read the research. Sarah also talks with science journalist Katherine Kornei about her story on changing athletic performance after gender transition. The feature profiles researcher Joanna Harper on the work she has done to understand the impacts of hormone replacement therapy and testosterone levels in transgender women involved in running and other sports. It turns out within a year of beginning hormone replacement therapy, transgender women plateau at their new performance level and stay in a similar rank with respect to the top performers in the sport. Her work has influenced sports oversight bodies like the International Olympic Committee. In this month’s book segment, Jen Golbeck interviews Andrew Lawler about his book The Secret Token: Myth, Obsession, and the Search for the Lost Colony of Roanoke. Next month’s book will be The Book of Why: The New Science of Cause and Effect by Judea Pearl and Dana Mackenzie. Write us at sciencepodcast@aaas.org or tweet to us @sciencemagazine with your questions for the authors. This week’s episode was edited by Podigy. Download a transcript of this episode (PDF) Listen to previous podcasts. [Image: Henry Howe; Music: Jeffrey Cook]

Yes, humans are the only species with language, but how did we acquire it? New research suggests our linguistic prowess might arise from the same process that brought domesticated dogs big eyes and bonobos the power to read others’ intent. Online News Editor Catherine Matacic joins host Sarah Crespi to talk about how humans might have self-domesticated themselves, leading to physical and behavioral changes that gave us a “language-ready” brain. Sarah also talks with Micah Edelson of the University of Zurich in Switzerland about his group’s research into the role that “responsibility aversion”—the reluctance to make decisions for a group—might play when people decide to lead or defer in a group setting. In their experiments, the team found that some people adjusted how much risk they would take on, depending on whether they were deciding for themselves alone or for the entire group. The ones who didn’t—those who stuck to the same plan whether others were involved or not—tended to score higher on standardized tests of leadership and have held higher military rank. This week’s episode was edited by Podigy. Download a transcript of this episode (PDF) Listen to previous podcasts. [Image: Scaly breasted munia/Ravi Vaidyanathan; Music: Jeffrey Cook]

We now live in the Meghalayan age—the last age of the Holocene epoch. Did you get the memo? A July decision by the International Commission on Stratigraphy, which is responsible for naming geological time periods, divided the Holocene into three ages: the Greenlandian, the Northgrippian, and the Meghalayan. The one we live in—the Meghalayan age (pronounced “megalion”)—is pegged to a global drought thought to have happened some 4200 years ago. But many critics question the timing of this latest age and the global expanse of the drought. Staff writer Paul Voosen talks with host Sarah Crespi about the evidence for and against the global drought—and what it means if it’s wrong. Sarah also talks to staff writer Kelly Servick about her feature story on what happens when biocontrol goes out of control. Here’s the setup: U.S. Department of Agriculture researchers wanted to know whether brown marmorated stink bugs that have invaded the United States could be controlled—aka killed—by importing their natural predators, samurai wasps, from Asia. But before they could find out, the wasps showed up anyway. Kelly discusses how using one species to combat another can go wrong—or right—and what happens when the situation outruns regulators. This week’s episode was edited by Podigy. Download a transcript of this episode (PDF) Listen to previous podcasts. [Image: Melissa McMasters/Flickr; Music: Jeffrey Cook] 

Several thousand years ago the volcano under Santorini in Greece—known as Thera—erupted in a tremendous explosion, dusting the nearby Mediterranean civilizations of Crete and Egypt in a layer of white ash. This geological marker could be used to tie together many ancient historical events, but the estimated date could be off by a century. Contributing Correspondent Lizzie Wade joins host Sarah Crespi to talk about a new study that used tree rings to calibrate radiocarbon readings—and get closer to pinning down a date. The findings also suggest that scientists may need to change their standard radiocarbon dating calibration curve. Sarah also talks to Tony Belpaeme of Ghent University in Belgium and Plymouth University in the United Kingdom about his Science Robotics paper that explored whether people are susceptible to peer pressure from robots. Using a classic psychological measure of peer influence, the team found that kids from ages 7 to 9 occasionally gave in to social pressure from robot peers, but adults did not. This week’s episode was edited by Podigy, with help from Meagan Cantwell. Download a transcript of this episode (PDF) Listen to previous podcasts. About the Science Podcast [Image: Softbank Robotics; Music: Jeffrey Cook]

Small satellites—about the size of a briefcase—have been hitching rides on rockets to lower Earth orbit for decades. Now, because of their low cost and ease of launching, governments and private companies are looking to expand the range of these “sate-lites” deeper into space. Host Sarah Crespi talks with Deputy News Editor Eric Hand about the mods and missions in store for so-called CubeSats. And our newest podcast producer Meagan Cantwell interviews Quentin Grafton of Australian National University in Canberra and Brad Udall of Colorado State University in Fort Collins about something called the “irrigation efficiency paradox.” As freshwater supplies dry up around the world, policymakers and farmers have been quick to try to make up the difference by improving irrigation, a notorious water waster. It turns out that both human behavior and the difficulty of water measurement are plaguing water conservation efforts in agriculture. For example, when farms find they are using less water, they tend to plant ever-more-water-intensive crops. Now, researchers are trying to get the message out about the behavioral component of this issue and tackle the measurement problem, using cheap remote-sensing technology, but with water scarcity looming ahead, we have to act soon. This week’s episode was edited by Podigy. Download a transcript of this episode (PDF) Listen to previous podcasts. About the Science Podcast [Image: John A. Kelley, USDA Natural Resources Conservation Service; Music: Jeffrey Cook]

A new project out of the Center for Open Science in Charlottesville, Virginia, found that of all the experimental social science papers published in Science and Nature from 2010–15, 62% successfully replicated, even when larger sample sizes were used. What does this say about peer review? Host Sarah Crespi talks with Staff Writer Kelly Servick about how this project stacks up against similar replication efforts, and whether we can achieve similar results by merely asking people to guess whether a study can be replicated. Podcast producer Meagan Cantwell interviews Emily Brodsky of the University of California, Santa Cruz, about her research report examining why earthquakes occur as far as 10 kilometers from wastewater injection and fracking sites. Emily discusses why the well-established mechanism for human-induced earthquakes doesn’t explain this distance, and how these findings may influence where we place injection wells in the future. In this month’s book podcast, Jen Golbeck interviews Judea Pearl and Dana McKenzie, authors of The Book of Why: The New Science of Cause and Effect. They propose that researchers have for too long shied away from claiming causality and provide a road map for bringing cause and effect back into science. This week’s episode was edited by Podigy. Download a transcript of this episode (PDF) Listen to previous podcasts. About the Science Podcast [Image: Jens Lambert, Shutterstock; Music: Jeffrey Cook]

We are in the middle of what some scientists are calling the sixth mass extinction and not all at-risk species can be saved. That’s causing some conservationists to say we need to start thinking about “species triage.” Meagan Cantwell interviews freelance journalist Warren Cornwall about his story on weighing the costs of saving Canada’s endangered caribou and the debate among conservationists on new approaches to conservation. And host Sarah Crespi interviews Hope Michelsen, a staff scientist at Sandia National Laboratories in Livermore, California, about mysterious origins of soot. The black dust has been around since fire itself, but researchers never knew how the high-energy environment of a flame can produce it—until now. Michelsen walks Sarah through the radical chemistry of soot formation—including its formation of free radicals—and discusses soot’s many roles in industry, the environment, and even interstellar space. Check out this useful graphic describing the soot inception process in the related commentary article. This week’s episode was edited by Podigy. Download a transcript of this episode (PDF) Listen to previous podcasts. About the Science Podcast [Image: Darren Bertram/Flickr; Music: Jeffrey Cook]

Strawberries had both male and female parts, like most plants, until several million years ago. This may seem like a long time ago, but it actually means strawberries have some of the youngest sex chromosomes around. What are the advantages of splitting a species into two sexes? Host Sarah Crespi interviews freelance journalist Carol Cruzan Morton about her story on scientists’ journey to understanding the strawberry’s sexual awakening. In 2016, experimental Zika vaccines were swiftly developed in response to the emergence of serious birth defects in the babies of infected woman. Two years after the height of Zika cases, there’s so little spread of the virus in the Americas that it has stymied vaccine trials. Researchers hope to overcome this hurdle with “human challenge experiments”—vaccinating people, then intentionally infecting them with Zika to see whether they’re protected from the virus. Meagan Cantwell talks with staff writer Jon Cohen about his news story that highlights the risks and rewards of human challenge experiments. This week’s episode was edited by Podigy. Download a transcript of this episode (PDF) Listen to previous podcasts. About the Science Podcast [Image: Public domain; Music: Jeffrey Cook]

Meta-analyses—structured analyses of many studies on the same topic—were once seen as objective and definitive projects that helped sort out conflicts amongst smaller studies. These days, thousands of meta-analyses are published every year—many either redundant or contrary to earlier metaworks. Host Sarah Crespi talks to freelance science journalist Jop de Vrieze about ongoing meta-analysis wars in which opposing research teams churn out conflicting metastudies around important public health questions such as links between violent video games and school shootings and the effects of antidepressants. They also talk about what clues to look for when trying to evaluate the quality of a meta-analysis. Sarah also talked with three other contributors to our “Research on Research” special issue. Pierre Azoulay of the Massachusetts Institute of Technology (MIT) in Cambridge, Ben Jones of Northwestern University in Evanston, Illinois, and MIT’s Heidi Williams discuss the evidence for some hoary old scientific home truths. See whether you can guess who originally made these claims and how right or wrong they were: Do scientists make great contributions after age 30? How important is it to stand on the shoulders of giants? Does the truth win, or do its opponents just eventually die out? Read the rest of the package on science under scrutiny here. This week’s episode was edited by Podigy. Download a transcript of this episode (PDF) Listen to previous podcasts. About the Science Podcast [Image: Davide Bonazzi/@SalzmanArt; Show music: Jeffrey Cook; additional music: Nguyen Khoi Nguyen]

Science has often treated Indigenous people as resources for research—especially when it comes to genomics. Now, Indigenous people are exploring how this type of study can be conducted in a way that respects their people and traditions. Meagan Cantwell talks with contributing correspondent Lizzie Wade about a summer workshop for Indigenous scientists that aims to start a new chapter in genomics. We’ve known for decades that PCBs—polychlorinated biphenyls—are toxic and carcinogenic. In the 1970s and 1980s, these compounds were phased out of use in industrial and electronic applications, worldwide. But they are still in the environment—in soil and air—and in animal tissues, particularly those of killer whales. These toxic compounds start out at minute levels in tiny organisms, but as the small are eaten by the slightly larger, the PCB concentration increases—from plankton, to fish, to seals—until you are at killer whales with PCB-packed blubber. Ailsa Hall, director of the Sea Mammal Research Unit at St. Andrews University in the United Kingdom, talks with host Sarah Crespi about her group’s work measuring PCB levels in different killer whale populations and calculating the effect of PCBs on those populations 100 years from now. In this month’s book segment, Jen Golbeck interviews Damon Centola about his book How Behavior Spreads: The Science of Complex Contagions. You can listen to more books segment and read more reviews on our books blog, Books et al.  This week’s episode was edited by Podigy. Download a transcript of this episode (PDF) Listen to previous podcasts About the Science Podcast [Image: Public domain; Music: Jeffrey Cook] 

Hoping to spot subatomic particles called neutrinos smashing into Earth, the balloon-borne Antarctic Impulsive Transient Antenna (ANITA) detector has circled the South Pole four times. ANITA has yet to detect those particles, but it has twice seen oddball radio signals that could be evidence of something even weirder: some heavier particle unknown to physicists’ standard model, burrowing up through Earth. Science writer Adrian Cho joins host Sarah Crespi to discuss the possibility that this reading could lead to a big change in physics. Next, host Meagan Cantwell asks researcher Ben Dalziel what makes a bad—or good—flu year. Traditionally, research has focused on two factors: climate, which impacts how long the virus stays active after a sneeze or cough, and changes in the virus itself, which can influence its infectiousness. But these factors don’t explain every pattern. Dalziel, a population biologist in the Departments of Integrative Biology and Mathematics at Oregon State University in Corvallis, explains how humidity and community size shape the way influenza spreads. This week’s episode was edited by Podigy. Download a transcript of this episode (PDF) Listen to previous podcasts. About the Science Podcast [Image: Stuart Rankin/Flickr; Music: Jeffrey Cook]

A small isolated town in Colombia is home to a large cluster of people with fragile X syndrome—a genetic disorder that leads to intellectual disability, physical abnormalities, and sometimes autism. Spectrum staff reporter Hannah Furfaro joins host Sarah Crespi to discuss the history of fragile X in the town of Ricaurte and the future of the people who live there. Also this week, we talk about greening up grass. Lawns of green grass pervade urban areas all around the world, regardless of climate, but the cost of maintaining them may outweigh their benefits. Host Meagan Cantwell talks with Maria Ignatieva of The University of Western Australia in Perth and the Swedish University of Agricultural Sciences in Uppsala about how lawns can be transformed to contribute to a more sustainable future. This week’s episode was edited by Podigy. Download a transcript of this episode (PDF) Listen to previous podcasts. About the Science Podcast [Image: Adam Kerfoot-Roberts/Flickr; Music: Jeffrey Cook]

As you age, your cells divide over and over again, leading to minute changes in their genomes. New research reveals that in the lining of the esophagus, mutant cells run rampant, fighting for dominance over normal cells. But they do this without causing any detectable damage or cancer. Host Sarah Crespi talks to Phil Jones, a professor of cancer development at the University of Cambridge in the United Kingdom, about what these genome changes can tell us about aging and cancer, and how some of the mutations might be good for you. Most Western farmers apply their pesticides using drones and machinery, but in less developed countries, organophosphate pesticides are applied by hand, resulting in myriad health issues from direct exposure to these neurotoxic chemicals. Host Meagan Cantwell speaks with Praveen Vemula, a research investigator at the Institute for Stem Cell Biology and Regenerative Medicine in Bengaluru, India, about his latest solution—a cost-effective gel that can be applied to the skin to limit pesticide-related toxicity and mortality. This week’s episode was edited by Podigy. Download a transcript of this episode (PDF) Listen to previous podcasts. About the Science Podcast [Image:Navid Folpour/Flickr; Music: Jeffrey Cook]

A group of children is suing the U.S. government—claiming their rights to life, liberty, and property are under threat from climate change thanks to government policies that have encouraged the use and extraction of fossil fuels. Host Meagan Cantwell interviews news writer Julia Rosen on the ins and outs of the suit and what it could mean if the kids win the day.    Also this week, host Sarah Crespi talks with Andrew Moeller of Cornell University about his work tracing the gut microbes inherited through 10 generations of mice. It turns out the fidelity is quite high—you can still tell mice lineages apart by their gut microbes after 10 generations. And horizontally transmitted microbes, those that jump from one mouse line to another through exposure to common spaces or handlers, were more likely than inherited bacteria to be pathogenic and were often linked to illnesses in people. This week’s episode was edited by Podigy. Download a transcript of this episode (PDF) Listen to previous podcasts. About the Science Podcast [Image: Bob Dass/Flickr; Music: Jeffrey Cook] 

For a long time, Parkinson’s disease was thought to be merely a disorder of the nervous system. But in the past decade researchers have started to look elsewhere in the body for clues to this debilitating disease—particularly in the gut. Host Meagan Cantwell talks with Viviane Labrie of the Van Andel Institute in Grand Rapids, Michigan, about new research suggesting people without their appendixes have a reduced risk of Parkinson’s. Labrie also describes the possible mechanism behind this connection. And host Sarah Crespi talks with Peter Fratzl of the Max Planck Institute of Colloids and Interfaces in Potsdam, Germany, about what materials scientists can learn from nature. The natural world might not produce innovations like carbon nanotubes, but evolution has forged innumerable materials from very limited resources—mostly sugars, proteins, and minerals. Fratzl discusses how plants make time-release seedpods that are triggered by nothing but fire and rain, the amazing suckerin protein that comprises squid teeth, and how cicadas make their transparent, self-cleaning wings from simple building blocks. Fratzl’s review is part of a special section in Science on composite materials. Read the whole package, including a review on using renewables like coconut fiber for building cars and incorporating carbon nanotubes and graphene into composites. This week’s episode was edited by Podigy. Download the transcript (PDF) Listen to previous podcasts. About the Science Podcast [Image: Roger Smith/Flickr; Music: Jeffrey Cook]

A new report suggests a big increase in the use of monkeys in laboratory experiments in the United States in 2017. Online News Editor David Grimm joins host Sarah Crespi to discuss which areas of research are experiencing this rise and the possible reasons behind it. Also this week, host Meagan Cantwell talks with staff writer Adrian Cho about a final push to affix the metric system’s measures to physical constants instead of physical objects. That means the perfectly formed 1-kilogram cylinder known as Le Grand K is no more; it also means that the meter, the ampere, and other units of measure are now derived using complex calculations and experiments.  This week’s episode was edited by Podigy. Download a transcript (PDF) Listen to previous podcasts. About the Science Podcast [Image: Peter Nijenhuis/Flickr; Music: Jeffrey Cook] 

When was the worst year to be alive? Contributing Correspondent Ann Gibbons talks to host Sarah Crespi about a contender year that features a volcanic eruption, extended darkness, cold summer, and a plague. Also on this week’s show, host Meagan Cantwell talks with Andrea Di Francesco of the National Institutes of Health’s National Institute on Aging in Baltimore, Maryland, about his review of current wisdom on fasting and metabolism. Should we start fasting—if not to extend our lives maybe to at least to give ourselves a healthy old age?  In a special segment from our policy desk, Deputy Editor David Malakoff discusses the results of the recent U.S. election with Senior Correspondent Jeffrey Mervis and we learn what happened to the many scientist candidates that ran and some implications for science policy. This week’s episode was edited by Podigy. Download a transcript (PDF) Listen to previous podcasts. About the Science Podcast [Photo: Scott Suchman; Styling: Nichole Bryant; Music: Jeffrey Cook]