An Essential Difference? Males, Females, and the Spaces In Between
A new podcast episode with Agustín Fuentes explores the meaning of biological sex.
Binary thinking is out of fashion.
But what about biological sex?
Whatever we might say about diversity and fluidity, the idea of “male” and “female” seems essential in biology. I’ve taught biology. I’ve drawn 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. Sex cells are binary. 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.
I approached this topic with a mix of curiosity and scepticism. And while I'm still unsure of what to make of the conclusion, I do not regret the conversation one bit. We had a great chat, 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 in the comments!
Listen (1h01) : Apple Podcasts | Spotify | Other players
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Mentions
Augustín Fuentes—Sex is a Spectrum; Creative Spark; Race, Monogamy, and Other Lies They Told You)
Yuval Noah Harari—Sapiens, A Brief History of Humankind)
Jared Diamond—Guns, Germs, and Steel)
Steven Pinker—How the Mind Works)
Sara Blaffer Hrdy—Father Time)
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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 | flatworm c elegans sex | 5-alpha-reductase type 2 deficiency (5α-R2D) | PCOS (Polycystic Ovary Syndrome)