PNAS Science Sessions

A pterosaur and its ecosystem at the end of the Triassic Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Kay Behrensmeyer and Ben Kligman describe what a fossil bone bed in Arizona reveals about a 209-million-year-old pterosaur and its ecosystem. In this episode, we cover: •[00:00] Introduction •[01:01] Paleoecologist Kay Behrensmeyer and paleontologist Ben Kligman describe the discovery of this fossil bone bed. •[03:10] Kligman and Behrensmeyer introduce a previously undescribed pterosaur. •[05:00] They talk about what this specimen says about the ecology and evolution of pterosaurs. •[06:15] Kligman and Behrensmeyer talk about the importance of studying this fossil community. •[07:52] They explain how their methods can improve paleontology and discovery of small fossils. •[09:08] Behrensmeyer and Kligman talk about the study’s caveats and limitations. •[10:10] Conclusion. About Our Guests: Kay Behrensmeyer Curator of Paleobiology National Museum of Natural History, Smithsonian Institution Ben Kligman Postdoctoral Fellow National Museum of Natural History, Smithsonian Institution View related content here: https://www.pnas.org/doi/10.1073/pnas.2505513122 Follow us on Spotify, Apple Podcasts, or wherever you get your podcasts for more captivating discussions on scientific breakthroughs! Visit Science Sessions on PNAS.org: https://www.pnas.org/about/science-sessions-podcast  Follow PNAS: Twitter/X Facebook LinkedIn YouTube Sign up for the PNAS Highlights newsletter

The postglacial history of the Saimaa ringed seal Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Jaakko Pohjoismäki, Jukka Jernvall, and Ari Löytynoja discuss the evolutionary history of the Saimaa ringed seal. In this episode, we cover: •[00:00] Introduction •[01:06] Molecular biologist Jaakko Pohjoismäki introduces Lake Saimaa and the Saimaa ringed seal. •[02:30] Zoologist Jukka Jernvall talks about the characteristics of species isolated by glaciation. •[03:27] Evolutionary biologist and bioinformatician Ari Löytynoja explains the genetic and demographic methods of the study. •[04:11] Löytynoja and Jernvall explain why the results were surprising and where the study turned next. •[06:20] Pohjoismäki and Löytynoja describe the study’s implications for biodiversity in postglacial habitats. •[07:50] Jernvall and Löytynoja talk about the study’s caveats and limitations. •[10:14] Conclusion. About Our Guests: Jaakko Pohjoismäki Professor University of Eastern Finland Jukka Jernvall Professor University of Helsinki Ari Löytynoja University Lecturer University of Helsinki View related content here: https://www.pnas.org/doi/abs/10.1073/pnas.2503368122 Follow us on Spotify, Apple Podcasts, or wherever you get your podcasts for more captivating discussions on scientific breakthroughs! Visit Science Sessions on PNAS.org: https://www.pnas.org/about/science-sessions-podcast  Follow PNAS: Twitter/X Facebook LinkedIn YouTube Sign up for the PNAS Highlights newsletter

Managing eastern black rhinoceros populations with genetic studies Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Barbara Mable and Ronald Mellya show how allowing endangered rhinos to move between populations enhances genetic diversity. In this episode, we cover: •[00:00] Introduction •[01:00] Evolutionary geneticist Barbara Mable explains why is genetic diversity important in managing small, isolated populations of rhinos. •[02:59] Park warden Ronald Mellya describes how his firsthand experience with rhino management led to this study. •[04:52] Mable explains the methods of the study and the contributions of co-author Anubhab Khan. •[06:20] Mable talks about the results. •[07:24] Mellya tells how the study has changed rhino management in Tanzania. •[08:37] Mable and Mellya enumerate the caveats and limitations of the study. •[10:20] Conclusion. About Our Guests: Barbara Mable Professor University of Glasgow Ronald Mellya Park Warden Tanzania National Parks View related content here: https://www.pnas.org/doi/abs/10.1073/pnas.2414412122 Follow us on Spotify, Apple Podcasts, or wherever you get your podcasts for more captivating discussions on scientific breakthroughs! Visit Science Sessions on PNAS.org: https://www.pnas.org/about/science-sessions-podcast  Follow PNAS: Twitter/X Facebook LinkedIn YouTube Sign up for the PNAS Highlights newsletter

A reference genome aids efforts to rescue the northern white rhinoceros Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Franz-Josef Müller explains genomic tools to aid the functionally extinct northern white rhinoceros. In this episode, we cover: •[00:00] Introduction •[01:11] Multidisciplinary scientist Franz-Josef Müller introduces the northern white rhinoceros. •[01:55] He introduces induced pluripotent stem cells and why they’re important in efforts to save the northern white rhinoceros. •[04:20] He talks about the genomic risks of using induced pluripotent stem cells •[05:21] Müller tells the story of how he and his colleagues came together to complete the study. •[06:36] He explains how the northern white rhino’s genome was sequenced. •[07:58] He talks about the results and implications for stem cell genomic integrity. •[08:51] Müller enumerates the caveats and limitations of the study. •[10:24] Conclusion. About Our Guest: Franz-Josef Müller Professor University Hospital Schleswig-Holstein View related content here: https://www.pnas.org/doi/full/10.1073/pnas.2401207122 Follow us on Spotify, Apple Podcasts, or wherever you get your podcasts for more captivating discussions on scientific breakthroughs! Visit Science Sessions on PNAS.org: https://www.pnas.org/about/science-sessions-podcast  Follow PNAS: Twitter/X Facebook LinkedIn YouTube Sign up for the PNAS Highlights newsletter

Water and the possibility of life on Mars Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, researchers explain what we know about the potential for water and life on Mars and what we might learn from analysis of returned samples. In this episode, we cover: •[00:00] Introduction •[01:04] Mark Thiemens explains the importance of bringing samples from Mars back to Earth. •[02:37] Arya Udry explains the current gaps and limitations in the geological record provided by Martian meteorites. •[03:55] Bruce Jakosky explains what we currently know about the presence and history of water on Mars. •[05:26] Monica Grady explains how analyzing volatile species in Martian samples could provide insight into the planet’s past climate. •[06:58] Rachel Slank describes the potential presence of liquid brines on Mars. •[08:27] Vashan Wright used recordings from a seismometer onboard NASA’s InSight lander to estimate the volumes of liquid water that might be contained in the Martian mid-crust. •[10:14] Mark Sephton explains what biomarkers are and what kinds we might expect to find in Martian samples. •[11:34] Caroline Freissinet describes the discovery of long-chain organic molecules on Mars and the difficulties of conclusively identifying organic molecules as biomarkers. •[13:32] Thiemens explains the potentially far-reaching value of continuing to support the Mars Sample Return mission. •[14:37] Final thoughts and conclusion. About Our Guest: Mark Thiemens  Distinguished Professor of Chemistry and Biochemistry University of California at San Diego Arya Udry Associate Professor – Graduate coordinator University of Nevada, Las Vegas Bruce Jakosky Professor Emeritus University of Colorado Boulder Monica Grady Professor Emirita  Open University Rachel Slank Postdoctoral Fellow Lunar and Planetary Institute Vashan Wright Assistant Professor University of California, San Diego Mark Sephton Professor Imperial College London Caroline Freissinet Researcher Laboratory for Atmospheres, Observations, and Space French National Centre for Scientific Research View related content here: https://www.pnas.org/doi/10.1073/pnas.2421996121 https://www.pnas.org/doi/10.1073/pnas.2415280121 https://www.pnas.org/doi/full/10.1073/pnas.2404254121 https://www.pnas.org/doi/full/10.1073/pnas.2321080121 https://www.pnas.org/doi/full/10.1073/pnas.2404260121 https://www.pnas.org/doi/full/10.1073/pnas.2321067121 https://www.pnas.org/doi/full/10.1073/pnas.2409983121 https://www.pnas.org/doi/full/10.1073/pnas.2404256121 https://www.pnas.org/doi/full/10.1073/pnas.2420580122 Follow us on Spotify, Apple Podcasts, or wherever you get your podcasts for more captivating discussions on scientific breakthroughs! Visit Science Sessions on PNAS.org: https://www.pnas.org/about/science-sessions-podcast  Follow PNAS: Twitter/X Facebook LinkedIn YouTube Sign up for the PNAS Highlights newsletter

Using reinforcement learning to plan for an uncertain climate future Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Ning Lin talks about how reinforcement learning methods plant to mitigate climate risk despite uncertainty in climate change risk forecasts. In this episode, we cover: •[00:00] Introduction •[1:04] Civil engineer Ning Lin introduces why climate forecast uncertainty complicates risk management planning. •[02:41] Lin explains how reinforcement learning works. •[03:26] She talks about why the team studied risk management for Manhattan. •[04:54] Lin explains the results of the reinforcement learning study. •[05:40] She recounts the results that surprised her. •[07:25] Lin explains the takeaways from the study for emergency planners. •[09:00] She enumerates the caveats and limitations of the study. •[10:11] Conclusion. About Our Guest: Ning Lin Professor Princeton University View related content here: https://www.pnas.org/cgi/doi/10.1073/pnas.2402826122 Follow us on Spotify, Apple Podcasts, or wherever you get your podcasts for more captivating discussions on scientific breakthroughs! Visit Science Sessions on PNAS.org: https://www.pnas.org/about/science-sessions-podcast  Follow PNAS: Twitter/X Facebook LinkedIn YouTube Sign up for the PNAS Highlights newsletter

Insights in route planning from London taxi drivers Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Hugo Spiers, Pablo Fernández Velasco, and Eva-Marie Griesbauer share what they learned about human route planning from talking with London taxi drivers. In this episode, we cover: •[00:00] Introduction •[00:59] Cognitive neuroscientist Hugo Spiers reviews previous studies on human route planning. •[01:29] Cognitive scientist and philosopher Pablo Fernández Velasco talks about why they chose to study London taxi drivers. •[01:49] Spiers describes the test that qualifies London taxi drivers. •[02:39] Spiers explains the experimental procedure. •[04:01] A recording of a taxi driver describing a route. •[04:57] Fernández talks about the data analysis. •[05:22] Psychologist Eva-Maria Griesbauer talks about the experience of interviewing taxi drivers. •[05:56] Fernández, Spiers, and Griesbauer recount the results of the study. •[08:43] Fernández and Spiers talk about the implications for the study of human route planning. •[10:22] Fernández describes the caveats and limitations of the study. •[11:15] Conclusion. About Our Guests: Hugo Spiers Professor University College London Pablo Fernández Velasco Postdoctoral researcher University of York Eva-Maria Griesbauer Postdoctoral researcher University College London View related content here: https://www.pnas.org/doi/full/10.1073/pnas.2407814122 Follow us on Spotify, Apple Podcasts, or wherever you get your podcasts for more captivating discussions on scientific breakthroughs! Visit Science Sessions on PNAS.org: https://www.pnas.org/about/science-sessions-podcast  Follow PNAS: Twitter/X Facebook LinkedIn YouTube Sign up for the PNAS Highlights newsletter

Individual decision-making and collective animal behavior Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, researchers explore advances in the modeling of collective animal behaviors. In this episode, we cover: •[00:00] Introduction •[00:48] Conor Heins incorporated cognitive processes into a model of collective behavior. •[02:13] Eva Kanso analyzed how confinement influences collective behavior. •[03:41] Andreu Puy considered the role of speed in the leader-follower dynamics of schooling fish. •[04:45] Daniel Kronauer explored how a colony of clonal raider ants collectively responds to rising temperatures. •[06:02] Sonja Friman quantified the energy savings of starlings flying in complex formations. •[07:27] Daniele Carlesso modeled how weaver ants decide to form chains to explore their environment. •[08:43] Ashkaan Fahimipour explored how reef fish minimize the spread of misinformation. •[10:11] Clare Doherty explored the individualism of terrestrial hermit crabs moving in groups. •[11:44] Final thoughts and conclusion. About Our Guests: Conor Heins  Machine Learning Researcher Verses AI / Max Planck Institute of Animal Behavior Eva Kanso  Zohrab A. Kaprielian Fellow in Aerospace and Mechanical Engineering University of Southern California Andreu Puy  PhD Student Polytechnic University of Catalonia Daniel Kronauer  Stanley S. and Sydney R. Shuman Professor Rockefeller University Sonja Friman  Postdoctoral Fellow Lund University Daniele Carlesso  Postdoctoral Researcher University of Konstanz Ashkaan Fahimipour  Assistant Professor Florida Atlantic University Clare Doherty  Research Associate Ulster University View related content here: https://www.pnas.org/doi/full/10.1073/pnas.2320239121 https://www.pnas.org/doi/full/10.1073/pnas.2406293121 https://www.pnas.org/doi/full/10.1073/pnas.2309733121 https://www.pnas.org/doi/full/10.1073/pnas.2123076119 https://www.pnas.org/doi/full/10.1073/pnas.2319971121 https://www.pnas.org/doi/full/10.1073/pnas.2216217120 https://www.pnas.org/doi/full/10.1073/pnas.2215428120 https://www.nature.com/articles/s41598-022-11469-1 Follow us on Spotify, Apple Podcasts, or wherever you get your podcasts for more captivating discussions on scientific breakthroughs! Visit Science Sessions on PNAS.org: https://www.pnas.org/about/science-sessions-podcast  Follow PNAS: Twitter/X Facebook LinkedIn YouTube Sign up for the PNAS Highlights newsletter

Modeling extreme heat waves Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Kai Kornhuber explains how and why climate models struggle to reproduce extreme heat wave trends. In this episode, we cover: •[00:00] Introduction •[00:53] Extreme weather climatologist Kai Kornhuber explains why modeling heat waves is important. •[01:38] He talks about how the study modeled hotspots of anomalous heat wave activity. •[03:01] Kornhuber tells where the hotspots are located. •[04:17] He explains how well climate models reproduce these trends. •[06:43] He talks about ways climate modelers can improve model representation of heat waves. •[07:48] Kornhuber describes the caveats and limitations of the study.  •[09:08] He enumerates the key takeaways. •[10:18] Conclusion. About Our Guest: Kai Kornhuber Senior Research Scholar International Institute for Applied Systems Analysis View related content here: https://www.pnas.org/doi/full/10.1073/pnas.2411258121 Follow us on Spotify, Apple Podcasts, or wherever you get your podcasts for more captivating discussions on scientific breakthroughs! Visit Science Sessions on PNAS.org: https://www.pnas.org/about/science-sessions-podcast  Follow PNAS: Twitter/X Facebook LinkedIn YouTube Sign up for the PNAS Highlights newsletter

Reconsidering the social cost of carbon Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Frances Moore presents a re-analysis of how the social costs of carbon emissions are quantified. In this episode, we cover: •[00:00] Introduction •[00:50] Climate economist Frances Moore explains the “social cost of carbon.” •[02:21] She describes the background of the study.  •[03:35] She talks about the methods of the study, which included a survey of experts. •[05:18] Moore presents the results, including underestimation of the social cost of carbon. •[07:02] She talks about the policy implications of the study. •[08:35] Moore discusses the caveats and limitations of the study. •[09:21] Conclusion. About Our Guest: Frances Moore Associate professor University of California, Davis View related content here: https://www.pnas.org/doi/full/10.1073/pnas.2410733121 Follow us on Spotify, Apple Podcasts, or wherever you get your podcasts for more captivating discussions on scientific breakthroughs! Visit Science Sessions on PNAS.org: https://www.pnas.org/about/science-sessions-podcast  Follow PNAS: Twitter/X Facebook LinkedIn YouTube Sign up for the PNAS Highlights newsletter