Episode Nine– (Joel Cohen) “The Millenium Project”: Human Populations and Livelihood in the 21st Century

Episode Nine– (Joel Cohen) “The Millenium Project”: Human Populations and Livelihood in the 21st Century

In 1999, the American Philosophical Society held a symposium that gathered experts from around the world to make predictions about humanity in the 21st century. One of those experts, demographer and statistician Joel Cohen, met with host Patrick Spero to discuss this millennium’s trends and if we got them right in 1999. In this episode of Useful Knowledge, Cohen reviews his 1999 predictions on topics like population growth, economic equality, immigration, family dynamics, and more to share the outcomes, for better or worse, making recommendations for the coming decades.

Episode Eight– (Emily Sperou) Chasing an Apex Predator: Leopard Seals and Antarctic Survival

Dr. Emily Sperou is an ecobiologist and researcher who spent her doctoral studies and the first years of her postdoctoral career studying one of the world’s most elusive apex predators: the leopard seal. She and her colleagues take arduous boat trips through Antarctica, searching for rare animals and studying their diets, reproduction, and their survival amid climate change, melting polar ice, and changing sea levels. Sperou’s work helps inform policymakers and teach conservation groups about how to protect leopard seals and what their livelihood and survival means for the vast polar food web beneath them.

Episode Seven– “A Contemplative Life”: The Honorable David Tatel on Law, Judicial Restraint, and His Journey Through Blindness

David Tatel grew up believing in the power of law and science to make life better for everyone. He began doing that work himself, launching a decades-long career as a civil rights lawyer and later, as a judge in the United States Court of Appeals for the D.C. Circuit. He fought and decided cases on various topics, notably education, voting rights, environmental law, and disability protections. Along the way, disability took on a personal meaning in his life as he was diagnosed with retinitis pigmentosa, a degenerative eye disease that began to take away his vision. For much of his decades-long career as a lawyer and judge, he hid his failing vision. Writing his memoir, Vision: A Memoir of Blindness and Justice, gave Judge Tatel the time and space to reflect back on his 50 years in law and justice, and helped him rethink his relationship to his blindness. The book, along with his trusty guide dog, Vixen, helped him realize that his blindness is an essential part of his life and that "acknowledgement is better for everybody.” In this episode of Useful Knowledge, Judge Tatel joins host Patrick Spero to reflect on his philosophy of judicial restraint, his concerns about the future of American law, and becoming the role model he never had.

Episode Six– Serendipity in Scientific Discovery: Michael Marletta on the History and Future of Biochemistry

Before becoming a respected biochemist, Michael Marletta was a child watching Sputnik crossing over Rochester, New York, imagining what it might be like to be a scientist one day. He was his mother’s helper in the kitchen, wondering how spices got their flavor and how they changed when mixed together and heated. He admired the periodic table and the unbelievable truth that those simple elements make up all of life on Earth. As he explored the field of chemistry, he realized the Earth itself is the best biochemist of all–putting all the elements together to shape life as we know it.  In this episode of Useful Knowledge, host Patrick Spero is joined by biochemist Michael Marletta (APS 2016) to discuss how he found his niche in biochemistry and the future of the field for budding scientists. They consider the fascinating history of biochemistry from its earliest days when scientists were encouraged to smell and even taste their creations, and the role of serendipity in scientific discovery. And, Marletta shares one of the foundational chemicals in his work–nitric oxide, which has widespread effects throughout the human body.

Episode Five (Neil Shubin) – Frozen in Time and Space: What Ice can tell us about our Past, Present, and Future

Distant, freezing, barren–it may seem that the icy regions of the Arctic and Antarctica have nothing to do with life in warmer homes. In this episode of Useful Knowledge, Neil Shubin, paleontologist, evolutionary biologist, and APS Member, joins host Patrick Spero to explain how much these regions can tell us about the history and future of life on our planet and beyond. Shubin’s work has allowed him to crack open 380-million-year old rocks, uncovering histories of the times when the polar regions were tropical, meteorites and rocks from the Moon and Mars, and creatures that have evolved to survive in near-impossible conditions. What do scientists make of the freshwater lake hidden under Antarctica? Can polar ice release viruses onto our populace? What are the consequences of melting polar ice? In this episode, learn about these and other incredible findings.  Want to learn more? Look to Shubin’s 2025 book Ends of the Earth: Journeys to the Polar Regions in Search of Life, the Cosmos, and Our Future.