An Essential Difference? Males, Females, and the Spaces In Between ~ Augustín Fuentes
Binary thinking is out of fashion. But what about biological sex?Whatever we might say about diversity and fluidity, the ideas of “male” and “female” seem essential in biology. I’ve taught the subject. I’ve drawn bees and flowers, with arrows from anthers to ovaries. I’ve used the terms “dad cell” and “mother cell” while doing so. I don’t know how I could have done it any differently.And maybe that’s just fine. Human sex cells are binary: sperm and egg. But here’s the twist: humans aren’t sex cells. Humans are animals. And animals aren’t so easily grouped. XY chromosomes don’t always produce a penis. And when we turn to hormones, brains, and behaviours, the picture gets even messier.Or so argues Princeton Professor Agustín Fuentes, a leading expert on human biology. His new book, Sex Is a Spectrum, came out this week. It makes the case that biology no longer supports a sharp separation between male and female. Whether you agree with Fuentes or not, it’s an argument worth taking seriously.We had a great conversation, ranging from hermaphroditic worms to sex-changing fish, and from gender stereotypes to intersex humans. At times, I pushed back. But I learned a lot throughout the conversation. I hope you do too.Thoughts about Fuentes’s argument? Or my takes? Share them at onhumans.substack.com. You'll also find more links to dig deeper.Support the show: patreon.com/onhumansMENTIONSAgustín Fuentes: Sex is a Spectrum; Creative Spark; Race, Monogamy, and Other Lies They Told YouYuval Noah Harari: Sapiens, A Brief History of HumankindJared Diamond: Guns, Germs, and Steel Steven Pinker: How the Mind WorksSara Blaffer Hrdy: Father Time (see episode in April 2023)KEYWORDS Biological sex | gametes | chromosomes | intersex | hermaphrodite | sex determination | sexual dimorphism | sex-changing fish | clownfish biology | evolutionary biology | human evolution | Agustín Fuentes | anthropology of sex | reproductive biology | nonbinary biology | developmental biology | sex differences | male and female | sex in animals | sex in humans | genetics of sex | human biology | science of sex | sex vs gender | c. elegans sex | 5-alpha-reductase type 2 deficiency (5α-R2D) | PCOS (Polycystic Ovary Syndrome) |
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1:01:43
The Rest is History: From the Origins of Farming to the Dawn of Modernity ~ Johannes Krause
And so it ends! In the final episode of The Origins of Humankind, we explore the aftermath of the story so far—the story of how one peculiar species, Homo sapiens, evolved, spread, and outlived its relatives.Guiding us through this final chapter is Johannes Krause once again. Together, we uncover the emerging picture of the global spread of farming, pastoralism, and other key ingredients of modernity. Along the way, we explore some of the central questions of history—from the origins of inequality to the surprisingly pivotal role played by the peoples of the Eurasian steppe. (Yes, Mongols will make an appearance! But the story of the steppe goes much deeper...)As always, we end with my guest’s reflections on humanity.Enjoy!LINKSMore material: OnHumans.Substack.com/OriginsSupport the show: Patreon.com/OnHumansFree lectures on human origins: CARTAKrause's books: A Short History of Humanity; Hubris: The Rise and Fall of HumanityABOUT THE SERIESThe Origins of Humankind is produced by On Humans and UC San Diego's Centre for Academic Research and Training in Anthropogeny (CARTA). Other guests include Chris Stringer, Dean Falk, and Tim Coulson. KEYWORDSAnthropology | Biology | Human evolution | Human origins | Homo sapiens | Agriculture | Ancient DNA | Climate changes | Pleistocene | Holocene | Archaeology | Neolithic | Yamnaya | Bell Beakers | Proto Indo-Europeans | Ötzi Ice Man | Gunpowder Empires | Bantu-expansion | Austranesian expansion | Sami poeple | Y-chromosome bottleneck |
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1:03:25
A Human Like No Other: The Rise of Homo Sapiens ~ Johannes Krause
The time has come: This is where our story truly begins.In Episode 4 of The Origins of Humankind, we finally turn the spotlight on Homo sapiens. Guiding us through this journey is Johannes Krause, director of the Max Planck Institute for Evolutionary Anthropology and a pioneer of one of the greatest scientific revolutions of our time: the science of ancient DNA.This ability to extract DNA from fossils has transformed our understanding of the human past—giving us tools to tell a genuinely global history of our species. In this episode, we use the magic of ancient DNA to explore the world our species was born into: a weird, wild Ice Age planet teeming with other human species, from Flores Hobbits to Neanderthal Giants. We touch on big questions, such as:How did Homo sapiens spread around the world?Why were our ancestors so successful? How did climate changes shape their story?What was palaeolithic life like?What happened to the Neanderthals? (Be prepared for a plot twist!)We end at the dawn of the Holocene—the warm, wet period that would give rise to farming, cities, and everything we call “history.” That’s the story we’ll tackle in the final episode of The Origins of Humankind. Stay tuned. And enjoy this episode!LINKSMore material: OnHumans.Substack.com/OriginsSupport the show: Patreon.com/OnHumansFree lectures on human origins: CARTAKrause's books: A Short History of Humanity; Hubris: The Rise and Fall of HumanityABOUT THE SERIESThe Origins of Humankind is produced by On Humans and UC San Diego's Centre for Academic Research and Training in Anthropogeny (CARTA). Other guests include Chris Stringer, Dean Falk, and Tim Coulson. KEYWORDSAnthropology | Biology | Human evolution | Human origins | Homo Erectus | Australopithecines | Brain evolution | Paleoneurology | Hominins | DNA | Homo sapiens | Climate changes | Pleistocene | Cognitive evolution | Cognitive archaeology | Stone tools | Palaeolithic | Neanderthals | Homo floresiensis | Denisovans | Homo longi | Sima de los Huesos | Gravettian | Cannibalism | Aurignacian | Svante Pääbo |
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1:10:09
What Is a Human? The New Science of the Genus Homo ~ Chris Stringer
Things are about to get personal... In episode 3 of The Origins of Humankind, we zoom into the birth and spread of humanity itself. Our guide is the iconic Chris Stringer, one of the most influential paleoanthropologists alive. Together, we trace the origins of our genus and the emergence of Homo sapiens as the last surviving human species. While doing this, we meet many oddities, such as rhino hunting along the River Thames, but we also explore some of the biggest questions in human evolution:What is a human?Why did we evolve big brains?Why do we have such long childhoods?Is Homo sapiens truly unique — or just one human among many?As always, we finish with my guest's reflections on humanity.MORE LINKSMore material: OnHumans.Substack.com/OriginsSupport the show: Patreon.com/OnHumansFree lectures on human origins: CARTAStringer's books: Lone Survivors; Our Human StoryWHAT'S NEXT#4-5: The Story of Sapiens, in Two PartsThe series finishes with two episodes on the story of Homo sapiens, using the magic of ancient DNA to tell a genuinely global history of our species.Key question: How did migrations shape the human story? Why are we the only humans left? And how did humans spread worldwide, first as hunters and gatherers, then as farmers and shepherds?Your guide: Johannes Krause was the first scholar to discover a new species of humans by DNA alone. Co-author of Hubris, and A Short History of Humanity, he is now the Director of the Max Planck Institute of Evolutionary Anthropology.When: March 16th & 23rd, 2025KEYWORDSAnthropology | Biology | Human evolution | Human origins | Homo Erectus | Australopithecines | Brain evolution | Paleoneurology | Hominins | Cave art | Homo sapiens | Climate changes | Pleistocene | Cognitive evolution | Cognitive archaeology | Stone tools | Palaeolithic | Neanderthals | Alloparenting | Expensive tissue -hypothesis | Radiator theory | Brain growth | Palaeoanthropology |
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1:06:17
An Unusual Ape: The Deep Origins of Our Human Oddities ~ Dean Falk
The story continues! In part 2 of the Origins of Humankind, we trace the first steps of our ancestors after they left the chimpanzee lineage.To get humanity going, our ancestors had to wander through millions of years of what anthropologist Dean Falk has called the Botanic Age. It's a time shrouded in mist, yet it may hold the key to some of humanity’s most defining traits — from language and music to our clumsy toes and our large brains.On this walk through the mysteries of the Botanic Age, our guide is Dean Falk herself. She is a Distinguished Professor of Anthropology and the world's leading expert on human brain evolution. Together, we try to make sense of topics such as:The common ancestor between humans and chimpanzeesAgainst “Man the Toolmaker”: Tool use in other apesThe walking ape: how bipedalism shaped our ancestorsOrigins of languageOrigins of musicSize matters, but… The early evolution of the human brainAs always, we finish with the guest’s reflections on humanity.MORE LINKSMore stuff (including written highlights): OnHumans.Substack.com/OriginsSupport the show: Patreon.com/OnHumansFree lectures on human origins: CARTADean Falk’s book: The Botanic AgeWHAT'S NEXTOrigins of Humankind #3: What Is a Human?The stage has been set. It is time for humanity to enter. But what is a human? What makes a skeleton fall into the Genus "Homo"? And why did this puzzling genus evolve?Key questions: Why did humans evolve? And how do modern humans differ from Neanderthals or other extinct humans?Our guide: Chris Stringer is an iconic figure in the field, best known for his groundbreaking work towards the widely accepted Out of Africa -theory of human evolution. His career at London’s Natural History Museum stretches across five decades. When: April 9th, 2025KEYWORDSAnthropology | Primatology | Human evolution | Human origins | Homo Erectus | Australopithecine | Australopithecus africanus | Brain evolution | Paleoneurology | Apes | Great apes | Chimpanzees | Bonobos | Gorillas | LSA | Cognitive evolution | Cognitive archaeology | Baby slings | Motherse | Parentese | Baby talk | Putting the baby down -hypothesis | Radiator theory | Biology | Honinins | Hominoids | Palaeolithic Palaeoanthropology |
Where do we come from? What brings us together? Why do we love? Why do we destroy?
On Humans features conversations with leading scholars about human nature, human condition, and the human journey. From the origins of war to the psychology of love, each topic brings fresh insights into perennial questions about our self-understanding.
Support: Patreon.com/OnHumans
Articles: OnHumans.Substack.com
Focus areas: Anthropology, Psychology, Archaeology, Philosophy, Big History
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