On Humans

Apologies for the slow start to 2026! Something big is coming soon. Stay tuned for the announcement next week. Whilst waiting, you can enjoy one of my all-time favourites from the archives.A lot of the recent episodes have mentioned the impact of bipedalism in the human story, but the remarks have hardly done justice to the depth of the matter. Jeremy DeSilva did it justice.Enjoy! ORIGINAL SHOW NOTESHumans are odd in many ways. But perhaps the oddest of our features is our upright posture. We walk on two legs. And we are the only mammal to do so. So why do we walk upright? And why does it matter? Jeremy DeSilva is a fossil expert and a professor of paleoanthropology at Dartmouth College. He is also the author of a remarkable book, aptly titled First Steps: How Upright Walking Made Us Human DeSilva’s treatment of the subject is sweeping: while tracing the journey of human posture, he draws remarkable links between bipedalism and many facets of the human condition, from difficult births to complex language and from lower back pains to the beauty of friendships.In this episode, we talk about questions such as:What Darwin got right and wrong about the role of walking in human evolution When and why did we start walking upright?Why the common picture of human evolution is wrong - and what would be a better pictureWhy walking makes us fragileHow our ancestors survived bone fractures - and why this is a big deal Why is human birth so difficultWhy walking is so good for us: introducing the “myokines”What studying the human journey has taught DeSilva about our species_________Please consider becoming a supporter of On Humans. Even small monthly donations can make a huge impact on the long-term sustainability of the program. Visit: ⁠⁠Patreon.com/OnHumans ⁠⁠_________Names mentionedCharles Darwin / Ian Tattersall / Donald Johanson / Mary Leakey / Sherwood Washburn / Richard Wrangham (ep 21) / Kristen Hawkes (ep 6) / Holly Dunsworth / Daniel Lieberman Mentioned hominin speciesSahelanthropus / Ardipithecus / Australopithecus (e.g. Lucy) / Homo habilis / Homo erectus / Homo sapiens

Denise Su, a paleoecologist who reconstructs ancient environments, explores where humans evolved. She examines early hominins, foot anatomy and arboreal habits. She explains how isotopes, fauna and soils reveal diets and habitats. She unpacks climate-driven forest loss, the range of savannas, adaptability and the rise of Homo erectus with long-distance walking and thermoregulation.

Richard B. Lee, Canadian anthropologist who spent decades with Kalahari foragers, reflects on the 1966 Man the Hunter symposium. He recounts meeting the Ju/'hoansi, debates around the Original Affluent Society, gendered roles in foraging, shifts from foraging to farming, and how ecology shapes social inequality. Short, thoughtful stories and big-picture reflections throughout.

Manvir Singh, an anthropologist at UC Davis and author of 'Shamanism: The Timeless Religion', dives into the fascinating world of shamanism. He explores how varied practices evolve and intertwine with modern life, breaking down exotic perceptions versus scholarly definitions. Discussions include the transformative power of trances, the cultural markers that define shamans, and the intriguing connections between shamanism and major religions, even pondering if figures like Jesus had shamanic traits. Singh argues for the persistent relevance of shamanic practices in today's spiritual landscape.

Join renowned experts as they unravel the mysteries of human origins. Tim Coulson discusses how the extinction of dinosaurs paved the way for primates. Chris Stringer explains how dietary changes fueled brain growth. Dean Falk reveals how bipedalism influenced the development of music and language. Johannes Krause shares fascinating insights on Denisovans and the coexistence of multiple human species. Dive into the evolution of Homo sapiens and the challenges of agriculture, shaping our journey through time.

Mira Magdalena Sickinger, a poet and humor philosopher from the University of Vienna, explores the intricate role of humor in our lives. She discusses the risky social contracts of joke-telling and how humor reflects shared experiences. Their conversation dives into theories from Freud to Kant, revealing how laughter signals social bonds and coping mechanisms. Mira also delves into the politics of humor, examining its potential to challenge power dynamics and reflect societal truths, highlighting its profound connection to the human condition.

Andrés Moreno-Estrada, a prominent Mexican geneticist and expert in Latin American population genetics, dives into the epic migrations of humans from Africa to the Americas and Polynesia. He discusses the dominant ancestral source of Native Americans and the contrast in indigenous ancestry retention between North and South America. Notably, he shares emerging evidence of genetic links between Polynesia and the Americas and highlights how island genetics amplify ancient admixture signals. The conversation delves into the navigational skills of Polynesians and the fascinating timing of their exploratory voyages.

In this engaging discussion, Diyendo Massilani, a researcher at Yale School of Medicine specializing in ancient DNA and human adaptations, explores the complexities of human evolution and genetic diversity. He reveals counter-intuitive insights about the Out of Africa theory and emphasizes the deep genetic divergences within African populations. Massilani also highlights how superficial traits can mislead us and shares fascinating details on how lighter skin evolved in response to environmental pressures. Mixing and admixture, he argues, are key to understanding human innovation.

In this engaging discussion, David Gokhman, a researcher at the Weizmann Institute of Science, sheds light on the fascinating world of ancient DNA and its revelations about Neanderthals. He explores the remarkable differences in brain structure and function between archaic humans and modern ones, particularly highlighting unexpected roles of the cerebellum. Gokhman also discusses the genetic impact of interbreeding, showcasing how these interactions shaped our species and hint at the complexities of language evolution.

Explore the fascinating debates surrounding human origins, where a single accessible story might emerge. Delve into the paradox of why humans exist at all, and the evolution of primates from post-dinosaur mammals. Discover how tree-dwelling shaped prolonged childhoods, and the trade-offs of bipedalism. Hear about the importance of community caregiving and the role of nutrition in brain development. Finally, reflect on the unresolved questions of language origins amidst the story of our evolution from early primates to Homo sapiens.