Learn about why magic mushrooms evolved to be “magic” and new research into when children develop “theory of mind.” Magic mushrooms evolved to scramble insect brains by Cameron Duke Hallucinogenic mushrooms drug profile. (2020). Europa.eu. https://www.emcdda.europa.eu/publications/drug-profiles/hallucinogenic-mushrooms_en Lee, N., & Benji Jones. (2021, April 27). How psychoactive psilocybin in magic mushrooms changes your brain. Business Insider; Business Insider. https://www.businessinsider.com/magic-mushrooms-psilocybin-psychoactive-drug-brain-denver-legal-2019-5 Reynolds, H. T., Vijayakumar, V., Gluck-Thaler, E., Korotkin, H. B., Matheny, P. B., & Slot, J. C. (2018). Horizontal gene cluster transfer increased hallucinogenic mushroom diversity. Evolution Letters, 2(2), 88–101. https://doi.org/10.1002/evl3.42 The classic experiment testing children's theory of mind is flawed by Grant Currin Children do not understand concept of others having false beliefs until age 6 or 7. (2021, September 28). EurekAlert! https://www.eurekalert.org/news-releases/929684 Fabricius, W. V., Gonzales, C. R., Pesch, A., Weimer, A. A., Pugliese, J., Carroll, K., Bolnick, R. R., Kupfer, A. S., Eisenberg, N., & Spinrad, T. L. (2021). Perceptual Access Reasoning (PAR) in Developing a Representational Theory of Mind. Monographs of the Society for Research in Child Development, 86(3), 7–154. https://doi.org/10.1111/mono.12432 Cassella, C. (2021). We Might Be Wrong About How Children Understand The Minds of Others at a Young Age. ScienceAlert. https://www.sciencealert.com/new-evidence-suggests-children-may-not-have-theory-of-mind-until-age-6-or-7 Follow Curiosity Daily on your favorite podcast app to learn something new every day withCody Gough andAshley Hamer. Still curious? Get exclusive science shows, nature documentaries, and more real-life entertainment on discovery+! Go to https://discoveryplus.com/curiosity to start your 7-day free trial. discovery+ is currently only available for US subscribers.
Learn about why magic mushrooms evolved to be “magic” and new research into when children develop “theory of mind.”
Magic mushrooms evolved to scramble insect brains by Cameron Duke
The classic experiment testing children's theory of mind is flawed by Grant Currin
Follow Curiosity Daily on your favorite podcast app to learn something new every day with Cody Gough and Ashley Hamer. Still curious? Get exclusive science shows, nature documentaries, and more real-life entertainment on discovery+! Go to https://discoveryplus.com/curiosity to start your 7-day free trial. discovery+ is currently only available for US subscribers.
Find episode transcript here: https://curiosity-daily-4e53644e.simplecast.com/episodes/magic-mushroom-evolution-and-when-kids-gain-theory-of-mind
CODY: Hi! You’re about to get smarter in just a few minutes with Curiosity Daily from curiosity-dot-com. I’m Cody Gough.
ASHLEY: And I’m Ashley Hamer. Today, you’ll learn about why magic mushrooms evolved to be “magic” in the first place; and new research that changes what we thought about when kids develop “theory of mind.”
CODY: Let’s satisfy some curiosity.
Some mushrooms are magic, if you know what I mean. That “magic” comes from a molecule the mushrooms make called psilocybin, which has hallucinogenic effects. We've talked about psilocybin on the show before, but we've yet to answer an important question about it. That is, why do mushrooms make it in the first place?
We’re not the first to ask that question. Researchers studying the evolution of psilocybin wanted to know too, and they found something a little weird when they looked into it. There are fifty known mushroom species that produce psilocybin, but they’re not all related to one another. Typically, a complex trait like psilocybin production is found in related species because it evolved in a common ancestor. But in this case, it seems to have been acquired across multiple genetic lineages.
But that’s not to say that each species evolved it independently. Instead, the evidence suggests that psilocybin evolved in one species before being passed along to others through a process called horizontal gene transfer. That’s where genetic material is passed from one species to another through either viruses or by picking up DNA in the environment. That’s something that happens a lot with bacteria, but rarely in fungi.
Psilocybin must be important if all these unrelated species stole it and continue to produce it — especially since it’s costly to make. And it is, because it’s used as a weapon to defend against the arch-nemesis of fungi and picnics alike: ants.
The species that produce psilocybin tend to survive by decomposing material like dung and wood that falls on the forest floor. This means that they not only have to defend themselves from ants that eat mushrooms, but also ants that eat wood and dung. They’re fighting a war on two fronts, and psilocybin is a powerful weapon in the fight.
Because psilocybin targets neurotransmitter receptors, ants that ingest it will at the very least change their behavior — say, by becoming less hungry. But at the extreme end, they might experience an ant version of a hallucination. Scientists aren’t sure. But whatever psilocybin does, it’s undoubtedly effective at tripping up anything that comes its way.
How old are kids before they start to imagine what other people are thinking? According to a new study from a team of psychologists, the answer we thought we knew might be wrong. And they figured this out by putting a twist on a classic experiment that explores a concept called “theory of mind.”
To understand this idea, imagine you’re a preschooler watching this scene unfold: A kid named Maxi walks into a room carrying a chocolate bar. He walks up to a table with 2 boxes, one blue, the other green. Maxi puts his chocolate bar in the blue box and leaves. Once he’s gone, Maxi’s mom comes in, takes the chocolate bar out of the blue box, and puts it into the green box. Then she leaves. Finally, Maxi comes back into the room to get the chocolate bar.
Here’s the question for you: where does Maxi look?
Researchers have been asking 4- and 5-year-olds this question for decades, and about 90 percent of them say that he’ll look where he put the chocolate bar originally: the blue box. That makes sense because Maxi wasn’t there to see his mom move the chocolate bar. For many psychologists, this is proof that the preschoolers can imagine what Maxi is thinking. In other words, they’ve developed theory of mind.
But that might not be the right conclusion.
A team of researchers recently added just one more element to the experiment and found some surprising results. Maxi still puts his chocolate in the blue box and his mom still moves it to the green box. But there’s another box on the table: a red one that doesn’t get touched.
As usual, Maxi walks back into the room looking for the chocolate. When 4- and 5-year-olds were asked which box he would look in first, only half of them said he’d look in the blue box. The other half guessed the red box.
The researchers take this as evidence that 4- and 5-year-olds haven’t actually been imagining what it’s like to be Maxi. Instead of a theory of mind, these kids are using what the psychologists call perceptual access reasoning. The kids seem to be working off two basic beliefs. One, if you can’t see something you can’t know it. And two, if you don’t know something then you’ll always be wrong about it. That’s definitely a logic, but it’s not a theory of mind.
According to the researchers’ interpretation of their results, the 90% of kids who got it right when there were just 2 boxes weren’t actually imagining Maxi’s thought process. They just knew he didn’t know the truth. That distinction was invisible to psychologists when there was just one wrong answer. The researchers found that kids start reliably imaging what Maxi is thinking just a bit later than we thought, at 6 or 7.
The 5-year-olds didn’t know what Maxi was thinking — and it turns out that we didn’t know what they were thinking, either.
Let’s recap today’s takeaways
[ad lib optional]
ASHLEY: Today’s writers were Cameron Duke and Grant Currin.
CODY: Our managing editor is Ashley Hamer.
ASHLEY: Our producer and audio editor is Cody Gough.
CODY: [AD LIB SOMETHING FUNNY] Join us again tomorrow to learn something new in just a few minutes.
ASHLEY: And until then, stay curious!