PNAS Science Sessions

Determining how well extinct animals could smell 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, Quentin Martinez describes a reconstruction of olfactory capabilities in extinct mammals. In this episode, we cover: •[00:00] Introduction •[01:14] Evolutionary biologist Quentin Martinez tell why we want to reconstruct olfaction in extinct animals. •[02:35] He introduces the olfactory bulb endocast, or space within the skull that contained the olfactory bulb, and explains why it's important in evaluating olfaction in extinct animals. •[04:24] Martinez talks about studying the genomics of chemoreceptor genes, in addition to the bony structure of the olfactory bulb endocast. •[05:23] He tells about the results of the study. •[07:46] Martinez lists possible insights from reconstructing extinct animals' olfaction. •[08:53] He lists the caveats and limitations of the study. •[10:16] Conclusion. About Our Guest: Quentin Martinez Postdoctoral researcher Natural History Museum, Stuttgart, Germany View related content here: https://www.pnas.org/doi/10.1073/pnas.2510575122 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

Hidden sustainability costs of AI 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 describe the sustainability impact of AI data centers. In this episode, we cover: •[00:00] Introduction •[01:20] Bronis de Supinski describes how the energy demands of AI data centers have increased in recent years and why improvements in data center energy efficiency will not necessarily reduce total energy expenditures •[03:08] Eric Masanet explains the difficulty of tracking and projecting the energy usage of AI data centers. •[05:12] Shaolei Ren describes the water usage and air pollution associated with AI data centers. •[07:30] Tevfik Kosar explains how AI might be leveraged as a tool to help address climate change and sustainability challenges. •[09:00] Final thoughts and conclusion. About Our Guests: Bronis de Supinski Chief Technology Officer Lawrence Livermore National Laboratory Eric Masanet Professor University of California Santa Barbara Lawrence Berkeley National Laboratory Shaolei Ren Associate Professor University of California Riverside Tevfik Kosar Professor University at Buffalo 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

Molecular regulation of mosquito biting timing 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, Laura Duvall introduces a potential pathway for disrupting the biting behavior of mosquitoes. In this episode, we cover: •[00:00] Introduction •[00:57] Mosquito neuroscientist Laura Duvall introduces us to the normal biting behavior of mosquitoes. •[02:46] She tells why the biting behavior of the Aedes aegypti mosquito is of particular interest. •[03:24] Duvall describes findings regarding how mosquitoes' responses to CO2 vary over times of day. •[05:37] She introduces the PDF peptide that might be regulating timing of biting behavior and explains how losing that peptide changed mosquitoes' behavior. •[08:07] Duvall talks about the takeaways from the study for control of mosquito-borne illnesses. •[08:53] She lists the caveats and limitations of the study. •[09:26] Conclusion. About Our Guest: Laura Duvall Assistant Professor Columbia University View related content here: https://www.pnas.org/doi/10.1073/pnas.2520826122 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

How well flu vaccines protect public health 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, Lauren Meyers explains what the 2022-2023 influenza season taught us about the effectiveness of flu vaccines. In this episode, we cover: •[00:00] Introduction •[01:16] Computational epidemiologist Lauren Meyers introduces the health and hospitalization burden of seasonal influenza. •[01:47] She defines vaccine effectiveness. •[02:37] Meyers describes the features of the 2022-2023 flu season. •[04:05] She describes how the researchers estimated the hospitalizations prevented by vaccination. •[05:11] Meyers tells how vaccination of young adults protected adults over 65 years of age. •[06:56] She describes the takeaways of the study for future flu seasons. •[08:08] Meyers lists the caveats and limitations of the study. •[09:49] Conclusion. About Our Guest: Lauren Meyers Professor University of Texas at Austin View related content here: https://www.pnas.org/doi/abs/10.1073/pnas.2505175122 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

Air quality and pet health 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, Sarah Shackleton shares climate lessons learned from 6 million-year-old ice. In this episode, we cover: •[00:00] Introduction •[01:02] Paleoclimate and ice scientist Sarah Shackleton introduces the information researchers can glean from ice cores. •[02:02] She recounts the age extent of previous ice cores. •[03:03] Shackleton describes the Allan Hills Ice Area. •[04:35] She describes the method for ascertaining the age of air in an ice core. •[05:49] She explains the results of the study and the insights into the climate in Antarctica over the last 6 million years. •[06:32] Shackleton talks about the ice at the base of the core, and the research implications of the study. •[08:13] Caveats and limitations of the study. •[09:11] Conclusion. About Our Guest: Sarah Shackleton Assistant scientist Woods Hole Oceanographic Institution View related content here: https://www.pnas.org/doi/abs/10.1073/pnas.2502681122 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

China's science leadership 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, James Evans explains how and why China's leadership in global science is rising. In this episode, we cover: •[00:00] Introduction •[00:56] Social and complex systems scientist James Evans recounts the recent history of the trajectories of science in the U.S. and in China. •[01:50] He explains how to measure a country's scientific leadership and introduces the data sources used in the study. •[04:18] Evans tells the results of the study, and talks about some areas of science in which China's leadership has particularly advanced. •[06:20] He lists the key takeaways from the study for policymakers and the benefits of global science engagement. •[08:47] Evans talks about the caveats and limitations of the work. •[09:54] Conclusion About Our Guest: James Evans Max Plofsky Professor of Sociology and Data Science University of Chicago View related content here: https://www.pnas.org/doi/abs/10.1073/pnas.2414893122 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

Genetic history of dog domestication 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 the impact of domestication on dog genetics and behavior. In this episode, we cover: •[00:00] Introduction •[01:00] Greger Larson explains how the history of gene flow between dogs and their wild relatives differs from what we know about other domestic species. •[02:38] Audrey Lin finds that low levels of wolf ancestry are found in almost two thirds of dog breeds. •[04:18] Linus Girdland Flink documents evidence of two genetic wolves on a remote Scandinavian island that may have been under human control. •[06:13] Clément Car explores how the mating systems of free-ranging village dogs could provide insight into canine domestication •[07:43] Katia Bougiouri explains how she used a statistical method to improve ancient genomes and what her results reveal about the history of inbreeding in dogs. •[09:21] Lachie Scarsbrook explains how he used museum specimens to reconstruct the history of inbreeding in German Shepherd Dogs. •[11:10] Eleanor Raffan analyzes genetic data and owner-submitted behavioral questionaries from 1,343 golden retrievers. •[12:54] Kathryn Lord finds that genetic testing cannot accurately predict canine behaviors. •[14:25] Final thoughts and conclusion. About Our Guest: Greger Larson Professor University of Oxford Audrey Lin Gerstner Postdoctoral Scholar American Museum of Natural History Linus Girdland Flink Lecturer University of Aberdeen Clément Car Postdoctoral Researcher University of Gdańsk Katia Bougiouri Postdoctoral Researcher University of Copenhagen Lachie Scarsbrook Postdoctoral Researcher University of Oxford, Ludwig Maximilian University of Munich Eleanor Raffan University Associate Professor University of Cambridge Kathryn Lord Postdoctoral fellow University of Massachusetts Chan Medical School View related content here: https://www.pnas.org/doi/10.1073/pnas.2528616122 https://www.pnas.org/doi/10.1073/pnas.2421768122 https://www.pnas.org/doi/10.1073/pnas.2421759122 https://www.pnas.org/doi/10.1073/pnas.2421756122 https://www.pnas.org/doi/10.1073/pnas.2416980122 https://www.pnas.org/doi/10.1073/pnas.2421755122 https://www.pnas.org/doi/10.1073/pnas.2421757122 https://www.pnas.org/doi/10.1073/pnas.2421752122 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

Air quality and pet health 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, Stephen Jarvis explores the health impacts of poor air quality on pets. In this episode, we cover: •[00:00] Introduction •[00:51] Environmental economist Stephen Jarvis explains how he became interested in the effects of air quality on pets. •[01:59] He talks about the similarities in exposure between humans and pets, and introduces the veterinary dataset used in the study. •[03:30] Jarvis explains the results of the study and the potential physiological effects of poor air quality. •[05:40] He talks about the implications of reducing air pollution for petcare and the takeaway messages of the study. •[08:17] Jarvis explains the caveats and limitations of the study. •[09:14] Conclusion. About Our Guest: Stephen Jarvis Assistant professor London School of Economics View related content here: https://www.pnas.org/doi/10.1073/pnas.2504553122 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 giant virus associated with oyster aquaculture mortality 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, Curtis Suttle and Kevin Xu Zhong explain how a previously unidentified virus may be connected to mass die-offs of farmed Pacific oysters. In this episode, we cover: • [00:00] Introduction • [01:03] Environmental virologist Curtis Suttle introduces the importance of the Pacific oyster to aquaculture. • [01:42] Suttle describes mass mortality events, including one he witnessed. • [02:42] Environmental microbiologist Kevin Xu Zhong talks about the methods used to identify the Pacific Oyster Nidovirus 1. • [03:53] Zhong describes the notable features of the nidovirus. • [05:19] Zhong and Suttle explain how the nidovirus merits designation of a nidovirus family. • [06:25] Suttle explores the takeaways for oyster farmers and regulators. • [08:15] He lists the caveats and limitations of the study. • [09:40] Conclusion. About Our Guests: Kevin Xu Zhong Research Associate University of British Columbia Curtis Suttle Professor University of British Columbia View related content here: https://www.pnas.org/doi/10.1073/pnas.2426923122 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

Swamp lights and bat sight 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 two spooky mysteries: the source of will-o'-the-wisps and how bats integrate vision with echolocation. In this episode, we cover: •[00:00] Introduction •[00:58] Richard Zare's background and expertise. •[01:26] Richard, have you ever seen will-o'-the-wisps in the wild? •[01:31] What did we already know about will-o'-the-wisps before your study? •[02:42] How could water droplets ignite methane? •[03:24] Tell us about the methods of your study. How did you explore this phenomenon? •[04:17] What are the broader implications of your findings, beyond just will-o'-the-wisps? •[05:20] What are the caveats or the limitations of the study? •[05:40] Laura Stidsholt's background and expertise. •[06:06] Laura, what can you tell us about the species you studied? •[06:25] What instruments did you attach to the bats? •[07:03] How did the bats' echolocation behavior compare in dark versus lit environments? •[08:14] What do the results suggest about the benefits of integrating information from multiple senses while hunting prey? •[08:58] What do the results imply about the potential impact of artificial light on bats? •[09:43] Final thoughts and conclusion. About Our Guests: Richard Zare Marguerite Blake Wilbur Professor of Natural Science Stanford University Laura Stidsholt Assistant Professor Aarhus University View related content here: https://www.pnas.org/doi/full/10.1073/pnas.2521255122 https://www.pnas.org/doi/full/10.1073/pnas.2515087122 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

Implications of a mutation in modern humans 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, Xiangchun Ju and Svante Pääbo explore the evolutionary implications of a mutation that separates modern humans from ancestral hominins. In this episode, we cover: •[00:00] •[01:22] Neurobiologist Xiangchun Ju introduces the enzyme adenylosuccinate lyase, or ADSL, and its role in the synthesis of purine. •[02:09] Evolutionary anthropologist Svante Pääbo talks about the discovery of the A429V mutation, which is present in modern humans but not Neanderthals or Denisovans. •[03:38] Ju and Pääbo talk about the methods to humanize mice in order to study the evolutionary importance of the A429V mutation. •[05:04] They explain the results of the behavioral studies of the humanized mice. •[06:27] Pääbo explores the takeaways from the study. •[08:05] He contextualizes the study alongside other studies of modern human development. •[09:17] Pääbo and Ju list the caveats and limitations of the study. •[10:14] Conclusion. About Our Guests: Xiangchun Ju Postdoctoral scholar Okinawa Institute of Science and Technology Svante Pääbo Director Max Planck Institute for Evolutionary Anthropology View related content here: https://www.pnas.org/doi/10.1073/pnas.2508540122 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

Where primates evolved 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, Jorge Avaria-Llautureo and Chris Venditti explain why the evolution of primates likely occurred in cold, dry climates rather than in tropical forests. In this episode, we cover: •[00:00] Introduction •[00:58] Evolutionary biologist Jorge Avaria-Lautureo explains the prevailing hypothesis that primates evolved in a tropical climate •[02:54] Evolutionary biologist Chris Venditti introduces evidence suggesting a different origin climate. •[03:54] Avaria discusses how the researchers reconstructed the climate of early primate species. •[05:05] Venditti and Avaria explain why it was important to use standardized climate definitions in this study. •[07:29] Avaria describes the results of the study. •[08:18]Venditti talks about the importance of understanding early primates' climates. •[09:21] Avaria and Venditti talk about the study's caveats and limitations. •[10:22] Conclusion. About Our Guests: Jorge Avaria-Llautureo Postdoctoral scholar University of Reading Chris Venditti Professor University of Reading View related content here: https://www.pnas.org/doi/10.1073/pnas.2423833122 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

Climate change and lake oxygenation 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, Joachim Jansen explains how climate change altered cycles of oxygenation in lakes. In this episode, we cover: •[00:00] Introduction. •[00:56] Limnologist Joachim Jansen introduces us to the cycles of oxygenation in lakes throughout the seasons. •[02:35] He describes previous hypothesis about climate change and lake oxygenation and introduces the methods and datasets of the study. •[04:59] Jansen introduces the results of the study, including key differences between large and small lakes. •[06:54] He talks about the consequences of deoxygenation. •[09:03] Jansen explains the caveats and limitations of the study. •[09:37] Conclusion. About Our Guest: Joachim Jansen Postdoctoral Researcher University of Helsinki View related content here: https://www.pnas.org/doi/10.1073/pnas.2426140122 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 physics of the squash nick shot 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, Roberto Zenit explains the physics behind the unanswerable nick shot in the game of squash. In this episode, we cover: •[00:00] Introduction. •[00:56] Engineer Roberto Zenit introduces the game of squash, including his participation in the sport, and introduces the nick shot. •[02:11] He talks about the background and methods of the study. •[04:50] Zenit describes the mechanics of a nick shot. •[06:01] He talks about the implications of the study for squash players and for other applications. •[08:52] Zenit recounts the caveats and limitations of the study. •[09:41] Conclusion. About Our Guests: Roberto Zenit Professor Brown University View related content here: https://www.pnas.org/doi/10.1073/pnas.2505715122 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 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