Science Magazine Podcast

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] Learn more about your ad choices. Visit megaphone.fm/adchoices

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] Learn more about your ad choices. Visit megaphone.fm/adchoices

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] Learn more about your ad choices. Visit megaphone.fm/adchoices

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] Learn more about your ad choices. Visit megaphone.fm/adchoices

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] Learn more about your ad choices. Visit megaphone.fm/adchoices

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] Learn more about your ad choices. Visit megaphone.fm/adchoices

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] Learn more about your ad choices. Visit megaphone.fm/adchoices

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] Learn more about your ad choices. Visit megaphone.fm/adchoices

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] Learn more about your ad choices. Visit megaphone.fm/adchoices

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] Learn more about your ad choices. Visit megaphone.fm/adchoices