From the archive: Fermentation, fire, and our big brains
Many Minds
Hi friends, We're taking care of some spring cleaning this week. We'll be back in two weeks with a new episode. In the meantime, enjoy this favorite from our archives! - The Many Minds team ––––––––– [originally aired February 22, 2024] Brains are not cheap. It takes a lot of calories to run a brain, and the bigger your brain, the more calories it takes. So how is it that, over the last couple million years, the human brain tripled in size. How could we possibly have afforded that? Where did the extra calories come from? There's no shortage of suggestions out there. Some say...
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Howl, grunt, sing
Many Minds
The tree of life is a noisy place. From one branch come hoots and howls, from another come clicks and buzzes and whines. And coming from all over you hear the swell of song. But what is all this ruckus about? Why do so many animals communicate with sound? What kinds of meaning do these sounds convey? And—beyond the case of human speech—do any of these sounds merit the label of “language”? My guest today is , a zoologist at Cambridge University. Arik is an expert on vocal communication across the animal kingdom and the author of the recent book . Here, Arik and I talk about why the...
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The development of evolution
Many Minds
Evolution is not what it used to be. A lot has changed since Darwin's day. In the first half of the 20th century, evolutionary theory was integrated with an emerging understanding of genetics. Late in the 20th century, biologists started taking seriously the idea that organisms don't just adapt to their environments, they change them. Recently, researchers have started to acknowledge the role of culture in evolutionary processes. And so slowly our understanding of evolution has been reconsidered, updated, expanded. And more updates are underway. But it's not just our understanding of evolution...
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String theories
Many Minds
Where would our species be without string? It's one of our most basic technologies—so basic that it's easy to overlook. But humans have used string—and its cousins rope, yarn, cordage, thread, etc.—for all kinds of purposes, stretching back tens of thousands of years. We've used it for knots and textiles and fishing nets and carrier bags and bow-strings and record-keeping devices. It's one of the most ubiquitous, flexible, and useful technologies we have. But we haven't only put string to practical purposes. We've also long used it to tickle our minds. My guest today is . Roope is a...
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The other half of the brain
Many Minds
Neurons have long enjoyed a kind of rock star status. We think of them as the most fundamental units of the brain—the active cells at the heart of brain function and, ultimately, at the heart of behavior, learning, and more. But neurons are only part of the story—about half the story, it turns out. The other half of the brain is made up of cells called glia. Glia were long thought to be important structurally but not particularly exciting—basically stage-hands there to support the work of the neurons. But in recent decades, at least among neuroscientists, that view has faded. In our...
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A paradox of learning
Many Minds
How do we learn? Usually from experience, of course. Maybe we visit some new place, or encounter a new tool or trick. Or perhaps we learn from someone else—from a teacher or friend or YouTube star who relays some shiny new fact or explanation. These are the kinds of experiences you probably first think of when you think of learning. But we can also learn in another way: simply by thinking. Sometimes we can just set our minds to work—just let the ideas already in our heads tumble around and spark off each other—and, as if by magic, come away with a new understanding of the world. But how...
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From the archive: The octopus and the android
Many Minds
Happy holidays, friends! We will be back with a new episode in January 2025. In the meantime, enjoy this favorite from our archives! ----- [originally aired Jun 14, 2023] Have you heard of Octopolis? It’s a site off the coast of Australia where octopuses come together. It’s been described as a kind of underwater "settlement" or "city." Now, smart as octopuses are, they are not really known for being particularly sociable. But it seems that, given the right conditions, they can shift in that direction. So it's not a huge leap to wonder whether these kinds of cephalopod congregations could...
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Your brain on language
Many Minds
Using language is a complex business. Let's say you want to understand a sentence. You first need to parse a sequence of sounds—if the sentence is spoken—or images—if it's signed or written. You need to figure out the meanings of the individual words and then you need to put those meanings together to form a bigger whole. Of course, you also need to think about the larger context—the conversation, the person you're talking to, the kind of situation you're in. So how does the brain do all of this? Is there just one neural system that deals with language or several? Do different...
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Nestcraft
Many Minds
How do birds build their nests? By instinct, of course—at least that's what the conventional wisdom tells us. A swallow builds a swallow's nest; a robin builds a robin's nest. Every bird just follows the rigid template set down in its genes. But over the course of the last couple of decades, scientists have begun to take a closer look at nests—they've weighed and measured them, they've filmed the building process. And the conventional wisdom just doesn't hold up. These structures vary in all kinds of ways, even within a species. They're shaped by experience, by learning, by cultural...
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Animal, heal thyself
Many Minds
What happens to animals when they get sick? If they’re pets or livestock, we probably call the vet. And the vet may give them drugs or perform a procedure. But what about wild animals? Do they just languish in misery? Well, not so much. It turns out that animals—from bees to butterflies, porcupines to primates—medicate themselves. They seek out bitter plants, they treat wounds, they amputate limbs, they eat clay—the list goes on. This all raises an obvious question: How do they know to do this? How do they know what they know about healing and medicine? It also invites a related...
info_outlineThe idea of a "maternal instinct"—the notion that mothers are wired for nurturing and care—is a familiar one in our culture. And it has a flipside, a corollary—what you might call “paternal aloofness.” It's the idea that men just aren't meant to care for babies, that we have more, you know, manly things to do. But when you actually look at the biology of caretaking, the truth is more complicated and much more interesting.
My guest today is Dr. Sarah Blaffer Hrdy. She is Professor Emerita of Anthropology at the University of California, Davis and the author of the new book, Father Time: A Natural History of Men and Babies. In it, she examines paternal care, the biology that supports it, and the norms and practices that sometimes suppress it.
In this conversation, Sarah and I set her new book, Father Time, in the context of her four previous books. We discuss the surprising prevalence of male care in fish and amphibians. We talk about how Charles Darwin noted the plasticity of caretaking in animals, only to ignore that plasticity when talking about humans. We consider how time in intimate proximity with babies activates capacities for nurturing—not just in fathers, but in caretakers of all kinds. Along the way, we touch on langurs and owl monkeys; emus and cassowaries; cichlid fish and fairy shrimp; prolactin and oxytocin; patriarchy and patriarchal notions. We talk about what seems to be distinctive about the human capacity for care; and about what happens when males spend too much time competing for status, and not enough time snuggling babies.
You'll probably get a sense for this from our conversation, but there are very few researchers who take both biology and culture as seriously as Sarah Blaffer Hrdy does. She does not shy away from digging deep into either domain. And she does not shy away from trying to trace the tangled links between the two.
Alright friends, I hope you enjoy this one. On to my conversation with Dr. Sarah Blaffer Hrdy.
A transcript of this episode is available here.
Notes and links
3:00 – A classic paper on male parental care in fishes.
7:00 – Dr. Hrdy’s previous books include The Langurs of Abu, The Woman that Never Evolved, Mother Nature, and Mothers and Others.
13:00 – A academic article on “cooperative breeding” in birds.
16:30 – The full text of Charles Darwin’s book, The Descent of Man.
21:00 – Read about Caroline Kennard and her correspondence with Darwin here.
23:30 – A review of a recent book on Nancy Hopkins and her (quantitative) efforts to expose sexism at MIT.
26:00 – The 2014 paper on the brains of fathers in different caretaking roles.
37:00 – A paper by Larry Young and a colleague on the role of ancient peptides (like oxytocin) in sociality.
40:00 – The lab of Dr. Lauren O’Connell, who studies physiology and social behavior in poison dart frogs.
42:00 – A review of paternal care in primates.
47:00 – For more on Michael Tomasello’s “mutualism hypothesis”—and a lot else—see our earlier episode with Dr. Tomasello.
49:00 – For more on the costliness of the human brain, see our earlier episodes here and here.
58:00 – The 2007 study by Esther Herrmann, Michael Tomasello, and colleagues on the human specialization for social cognition.
59:00 – A study of children’s early “ostensive gestures” of showing and offering.
1:02:00 – An obituary for the ethnographer Lorna Marshall.
1:09:00 – An overview of ostracods and the traces they leave in the fossil record.
Recommendations
The Parental Brain, Michael Numan
Silas Marner, George Eliot
Endless Forms Most Beautiful, Sean Carroll
Your Inner Fish, Neil Shubin
Brave Genius, Sean Carroll
Many Minds is a project of the Diverse Intelligences Summer Institute, which is made possible by a generous grant from the John Templeton Foundation to Indiana University. The show is hosted and produced by Kensy Cooperrider, with help from Assistant Producer Urte Laukaityte and with creative support from DISI Directors Erica Cartmill and Jacob Foster. Our artwork is by Ben Oldroyd. Our transcripts are created by Sarah Dopierala.
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