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 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, is if by magic, come away with a new understanding of the world. But...
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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...
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The rise of machine culture
Many Minds
The machines are coming. Scratch that—they're already here: AIs that propose new combinations of ideas; chatbots that help us summarize texts or write code; algorithms that tell us who to friend or follow, what to watch or read. For a while the reach of intelligent machines may have seemed somewhat limited. But not anymore—or, at least, not for much longer. The presence of AI is growing, accelerating, and, for better or worse, human culture may never be the same. My guest today is . Iyad directs the at the Max Planck Institute for Human Development in Berlin. Iyad is a...
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How should we think about IQ?
Many Minds
IQ is, to say the least, a fraught concept. Psychologists have studied IQ—or g for “general cognitive ability”—maybe more than any other psychological construct. And they’ve learned some interesting things about it. That it's remarkably stable over the lifespan. That it really is general: people who ace one test of intellectual ability tend to ace others. And that IQs have risen markedly over the last century. At the same time, IQ seems to be met with increasing squeamishness, if not outright disdain, in many circles. It's often seen as crude, misguided, reductive—maybe a whole lot...
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Rethinking the "wood wide web"
Many Minds
Forests have always been magical places. But in the last couple decades, they seem to have gotten a little more magical. We've learned that trees are connected to each other through a vast underground network—an internet of roots and fungi often called the "wood wide web". We've learned that, through this network, trees share resources with each other. And we've learned that so-called mother trees look out for their own offspring, preferentially sharing resources with them. There's no question that this is all utterly fascinating. But what if it's also partly a fantasy? My guest today is ....
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Electric ecology
Many Minds
There's a bit of a buzz out there, right now, but maybe you haven’t noticed. It's in the water, it's in the air. It's electricity—and it's all around us, all the time, including in some places you might not have expected to find it. We humans, after all, are not super tuned in to this layer of reality. But many other creatures are—and scientists are starting to take note. My guest today is . Sam is a sensory ecologist at the Natural History Museum in Berlin, and one of a handful of scientists uncovering some shocking things about the role of electricity in the natural world. Here, Sam...
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The nature of nurture
Many Minds
The 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 . She is Professor Emerita of Anthropology at the University of California, Davis and the author of the new book, . In it, she examines...
info_outlineForests have always been magical places. But in the last couple decades, they seem to have gotten a little more magical. We've learned that trees are connected to each other through a vast underground network—an internet of roots and fungi often called the "wood wide web". We've learned that, through this network, trees share resources with each other. And we've learned that so-called mother trees look out for their own offspring, preferentially sharing resources with them. There's no question that this is all utterly fascinating. But what if it's also partly a fantasy?
My guest today is Dr. Justine Karst. Justine is a forest ecologist at the University of Alberta. Her research focuses on mycorrhizas—these are the symbioses formed between fungi and plant roots that are thought to be the basis of the "wood wide web." Last year, Justine and colleagues published a perspective piece in which they argued that some of the claims around the wood wide web have gotten out of hand. These new ideas about forests, they argued, have gotten decoupled from the actual on-the-ground—or under-the-ground—science. In reality, it’s a field still riddled with unknowns and mixed findings.
Here, Justine and I do a bit of mycorrhiza 101—we talk about what mycorrhizas are, how they evolved, and what the structures actually look like. We discuss the original 1997 study that inspired the term "wood wide web." We consider why it's so hard to figure out what's actually going on, mechanistically, under the forest floor. We discuss the increasingly popular notion of plant intelligence and what it means to empirical researchers in this area like Justine. We talk about why people—both members of the public and scientists themselves—have found wood wide web ideas so charming. And, finally, we discuss the question of whether a little bit of hype is really so bad—particularly if it gets people excited about forests, about science, and about conservation.
I got as excited about the "wood wide web" as anyone. The idea totally captured my imagination a couple of years ago. So I was intrigued—if also a little dismayed—to learn recently that these ideas were getting some pushback. And I knew immediately we should talk to one of the researchers leading that pushback.
Alright friends, let's get to it. On to my conversation with Dr. Justine Karst. Enjoy!
A transcript of this episode is available here.
Notes and links
5:00 – Popular treatments sometimes mentioned as over-hyping the wood wide web (and associated ideas) include The Hidden Life of Trees, Finding the Mother Tree, and the novel The Overstory.
9:30 – The landmark 1997 paper by Simard et al. that kicked off interest in the so-called wood wide web.
11:00 – A study showing that fungi are more closely related to animals than to plants.
11:30 – For more on the new interest in “plant intelligence” see our previous episodes here and here. On the notion of “fungal intelligence,” see here.
18:00 – A 1975 paper presenting a hypothesis about the origins of land plants.
20:00 – The California “mushroom bible” mentioned.
23:00 – A brief post (and infographic) on the differences between arbuscular mycorrhizas and ectomycorrhizas.
23:30 – Richard Powers’ influential novel, The Overstory. Note that the novel doesn’t exclusively focus on the wood wide web; it covers ideas and findings about trees and forests, many of which are uncontroversial.
36:00 – Dr. Karst co-authored her perspective piece in Nature Ecology & Evolution with Dr. Melanie Jones and Dr. Jason Hoeksema.
50:00 – For more on aspens and how they constitute clonal organisms, see here.
52:00 – The “mother tree” idea was popularized in Dr. Suzanne Simard’s book, Finding the Mother Tree.
1:04:00 – Another recent critique of the wood wide web and mother tree idea is here. In it the authors write: “Reaching out to the general public to make people care about forests is certainly a praiseworthy goal, but not when it involves the dissemination of a distorted view of the plant world. In other words: the end does not justify the means.”
1:05:30 – Others influenced by The Overstory include Barack Obama and Bill Gates.
1:09:00 – A primer on myco-heterotrophic plants.
1:13:00 – See a recent presentation by Dr. Jared Farmer on trees and “chronodiversity” here.
Recommendations
‘Seeing plants anew,’ Stella Stanford
‘Mother trees and socialist forests: Is the ‘wood-wide web’ a fantasy?’, Daniel Immerwahr
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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