On Humans

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.

Tim Coulson, an Oxford biologist and author, dives into the complexities of free will, linking it to the evolution of movement and the origins of behavior. He debates whether the universe is deterministic or random, highlighting quantum mechanics as a potential source of true randomness. Coulson explores intriguing concepts in quantum biology, like its role in photosynthesis and consciousness. He passionately argues how randomness influences our choices, while sharing his humanist outlook, emphasizing the unique privilege of scientific exploration.

Joining the discussion is Matthew Cobb, a renowned neuroscientist and author of 'The Idea of the Brain,' who dives into the intriguing history and limits of neuroscience. He elaborates on Galen's groundbreaking pig demonstration and the emergence of brain localization theories. Cobb discusses how drug discoveries in the 1950s shaped public perception, while highlighting the enigmatic nature of brain plasticity. He reflects on whether we can crack the neural code and shares insights on how studying the brain has influenced his understanding of humanity.

Judy Grisel, a neuroscientist and former addict, dives into the science of addiction and brain chemistry. She explores how dopamine shapes our desires and how substances like alcohol can sedate while rewarding. Grisel discusses the varied impacts of serotonin, contrasting SSRIs with psychedelics, and explains how modern behavioral addictions mirror drug-like effects. With hope for recovery, she emphasizes the importance of channeling cravings into positive pursuits and the empowering aspects of understanding addiction.

Join neurologist Pria Anand, author of The Mind Electric, as she dives deep into the intricacies of consciousness and the brain’s architecture. Anand reveals the musicality of sleep and the mysteries of REM and slow-wave sleep. She discusses the fascinating implications of seizures and how the split-brain findings illustrate the left hemisphere’s role in storytelling. Explore the nuanced relationship between memory and pain as she sheds light on the emotional capacities of the cerebellum. A captivating mix of science and humanity awaits!

Dean Falk, a paleo-neurologist, dives into the intriguing complexities of human brain evolution. She challenges conventional wisdom about brain size and cognitive function, highlighting how bipedalism influenced anatomical changes. Falk also discusses the unique aspects of Einstein's brain and the significance of areas like Broca's area in language development. Through fascinating case studies, she unravels the intricate relationship between brain morphology and our evolutionary journey, shedding light on the mysteries that make us human.

In a captivating discussion, Suzana Herculano-Houzel, a Brazilian neuroscientist and professor at Vanderbilt University, delves into the intriguing world of brain evolution. She challenges the long-held belief that larger brains mean higher intelligence, emphasizing neuron counts instead. Herculano-Houzel highlights the evolutionary advantages of cooking and technology, and how they shaped our cognitive abilities. With fresh insights on the cerebral cortex's role in decision-making, she explores human uniqueness while comparing our brains to those of other species, painting a new picture of intelligence and longevity.