StarTalk Radio - Cosmic Queries - The Fungus Among Us with Merlin Sheldrake

Episode Date: July 27, 2021

Can mushrooms take over your mind? On this episode, Neil deGrasse Tyson and comic co-host Matt Kirshen explore the weird world of fungi with fun-guy fungus expert and ecologist, Merlin Sheldrake. Could inactive spores survive space? NOTE: StarTalk+ Patrons can watch or listen to this entire episode commercial-free here: https://www.startalkradio.net/show/cosmic-queries-the-fungus-among-us-with-merlin-sheldrake/ Thanks to our Patrons Bradley Sheldrake, Marc Armstrong, The Warzone12, Luis Cruz, Ely, Andrea Sperini, and 1x4x9 for supporting us this week. Photo Credit: https://www.flickr.com/photos/calliope, CC BY 2.0, via Wikimedia Commons Subscribe to SiriusXM Podcasts+ on Apple Podcasts to listen to new episodes ad-free and a whole week early.

Welcome to StarTalk, your place in the universe where science and pop culture collide. StarTalk begins right now. This is StarTalk. Neil deGrasse Tyson here, your personal astrophysicist. This is going to be a Cosmic Queries edition on the subject of mushrooms. We're going to find out where they come from, what they're doing, and why, and especially what is their relationship to humans. And I got Matt Kirshen as my co-host.

Matt, how you doing, man? I'm very good, Neil. How's it going? It's been too long. Yeah, it's nice to be back. I miss you, and you're a host of, did I get it right, Probably Science? That is exactly it. Ah, it's getting late this time. Excellent.

I'm a one-time guest on your show. Emphasis on one time. We would have you back in a heartbeat. I never want to abuse my connections, friendships. Your access privileges. Okay, but I love it when you're out there just bringing science to the public in a whole other way. And you're an important sort of cog in a wheel that we're all trying to keep turning.

I appreciate that. We definitely are doing it in another way to the people who really know their stuff. And even if it's only probably science. I'm still good with that. Well, I think neither you nor I are mushroom experts, although I've eaten a few in my day. That's very true. We combed the world to find one of the world's experts, maybe the world's experts on this subject. And it's Merlin Sheldrake. Merlin, welcome to Star

Talk. Thanks for having me, Neil. It's good to be here. Yeah. So that accent that places you right in London right now, is that where you're coming from? That's right. So you're an ecologist, like a mushroom ecologist. You're also author. Your book just came out in paperback. I think the hardcover came out last year. But often paperbacks do much better than the hardback. So this will be anyone's chance to pick this up. And you can't miss it. If you want this book, if you love mushrooms, even if you don't love mushrooms but wonder what the hell are those things coming out of the ground. Entangled Life, how fungi make our worlds, change our minds, and shape our futures. That is ambitious, dude. So before we get to our Q&A with our fan base, I just want to sort of lay some groundwork here. So if you can tell us,

oh, but just, sorry, let me finish your pedigree here. You've got a PhD in tropical ecology from the University of Cambridge, right? And you specialized in the underground fungal networks in the tropical forests of Panama. This is just so exotic and like so fun. Maybe I'd do this if I weren't an astrophysicist. So can you just answer the question, what the hell is a mushroom? Because it doesn't have leaves. It doesn't, you know, it doesn't have photosynthesis. I think most people don't know what they are. So please illuminate us. So mushrooms are the fruiting bodies of fungi. And fungi are a kingdom of life. So that's as broad a category as animals or plants.

So fungi are a much bigger world than just mushrooms. Only a few fungal species, a few tens of thousands, produce mushrooms. But most live their lives as branching, fusing networks of tubular cells known as mycelium. Wow. So when did, you know, when I grew up, there was no mushroom kingdom, all right? That's how old I am.

So when did mushrooms decide that they should be... They got together as they do. They got together. In their networks. I missed that memo. When did that happen, please? Well, they won their independence, taxonomically speaking, in the late 60s.

Wow, so that's not quite in the textbooks that I would have had, because that's how old I am. Interesting. And so what were they considered before they were their own kingdom? Just plants? Yeah, so unglamorous, lower plants.

Lower. See, back then, so unglamorous lower plants. Lower. See, back then, everyone was putting higher and lower. They always got to rank things that way. That's just, that's not right. I think they do that. And so, but it's nonetheless a plant. I mean, it grows out of the ground.

So when I think of the animal kingdom and the plant kingdom, you're saying now the word plant does not include these spores that rise up out of the ground that we call mushrooms. That's right. So fungi are more closely related to animals than plants. And they also behave more like animals in their nutritional strategies. Plants photosynthesize. They build the energy that they need from the sun and carbon dioxide in the process of photosynthesis. But animals have to find food ready-made in the world,

which they then digest. And fungi have to do that too. So they're what's known as heterotrophs. Now, I think I knew that about their relationship, but I knew it only sort of indirectly. When I looked at the tree of life, what I learned was that the common ancestor between mushrooms and all animal life

split later than that common ancestor split from green plants and that blew my mind because i think that allows me to say what you just said that mushrooms and animals are more closely related that either of them are to green plants that am I allowed to say that upon knowing this about the tree of life? Yes. Damn. Okay, so now, so they grow, but they also, and we can eat them just as food, or we can ingest them. Who did the experiments to find out that mushrooms can affect us psychologically?

Is someone just going there? How does that work in practice? Well, it's a good question. So until the early part of the 20th century, there are only a few pockets of humans on the planet knew that some species of mushroom produced psychoactive compounds and would eat these mushrooms as part of their ritual and spiritual practices. That knowledge then spread to the West. And after that point, this handful of tropical species from Mexico were known to produce psilocybin mushrooms. But once

that became common knowledge, then people started to look all around the world and now over 200 species of fungi are known to produce psilocybin and it's very interesting that process because now how do you know um people test them psilocybin bruises blue when you um when you crush the the mushroom and so you can sometimes have a clue from the color you can have a clue from which species are closely related to each other or not, and which ones you might reasonably expect to be trippy. But there are always some surprises. So this chemical psilocybin? Psilocybin. So has that been isolated so that now you don't actually have to grow the mushroom? You just get it out of somebody's laboratory? That's right. It was actually first isolated and named by Albert Hoffman, the guy who discovered LSD.

But now in many of the studies that are being carried out, they use pure crystalline psilocybin produced in a lab. So he discovered it not while he was under the influence of LSD, presumably, because that completely messes with your capacity to think. Well, I mean... Interpret reality. I haven't heard that he was on LSD while he think. Well, I mean... Interpret reality. I haven't heard that he was on LSD while he was taking it, but you never know.

So how complicated is it to synthesize? Yeah, can we just do that in my kitchen? What do I need? Well, you need some... I would have thought that the easier way to get psilocybin in your kitchen would be to find a mushroom that has it rather than cutting up the lab,

but maybe I'm wrong. Let's ask him. No, I have a big chemistry kitchen. That's very true. I'm talking about the average person's kitchen. It's definitely true. It's easier to grow the mushrooms than it would be to set up a lab and go through all the analytic procedures

required to isolate, synthesize and isolate the molecule. So tell me about this and then we'll go straight to questions after this because I just want to lay some groundwork here. This mycelium, so I hosted this series on Cosmos, and we spent an entire episode, most of an episode, talking about the mycelium. But at the time, I didn't uniquely associate it with mushrooms themselves. I thought of it as just sort of this plant network where all the

plants are sort of communicating. But are you saying mushrooms have their own mycelium or they participate in a larger mycelium of the plant kingdom as well? So mycelium is a fungal talent and not a plant talent. And so fungi make mycelium. some of those fungal species produce mushrooms that we see many of them don't produce mushrooms and these different fungal species whether they produce mushrooms or not and some of them will relate to have relationships intimate trading relationships with plants and so plug into plants and they exchange nutrients and some of those fungal networks can plug into multiple plants at the same time. And those plants are also promiscuous, can plug into multiple fungal networks. And the result is shared

overlapping networks of plants and fungi. And that's what's referred to by the wood wide web. I think what you meant there. The wood wide web. I think that's what it was. Yeah. I'm curious about something. We have this impression that fungi just sort of spontaneously appear because if you leave food in the fridge for too long, it gets moldy. I once lived in a pretty grotty shared house where we broke the toilet at a party, and then a week later, because no one fixed it, there were mushrooms growing out of the carpet.

So that kind of thing can happen. How many spores of fungi are just generally in the air all the time? Because there must be the spores originally for them to then land on something and then start to grow. Lots. In fact, fungal spores. Exactly how many? Lots. I mean, so I've got a number if you want. 50 million tons of fungal spores are produced and released into the air every year, which is the weight of 500,000 blue whales. And these spores are such a large presence in the atmosphere that

they can precipitate the water droplets that go on to form clouds and rain, so they can change the weather. Wow. Just in case people don't know, you can more readily generate a raindrop if there's something to nucleate the condensation on, and it greatly enhances that process.

So, yeah, I didn't know. So it's raining mushrooms is what you're telling us. I'm glad I asked that now because that was a hell of an answer. Yeah, that was great. Let's go to questions, Matt. All right, well, there's a couple that Neil's hell of an answer. Yeah, that was great. Let's go to questions, Matt. What do you have? Well, there's a couple that Neil's already touched on with his questions, but I just want

a slightly more specific answer from Teresina Rojas' question. What are the differences between plants and fungi? And then also, which ones evolve first? I believe the answer to that is mushrooms evolve first and fungi evolve first. No. Plants, I think.

So first, first he does. We'll let him answer the question. Yeah, that would be the other way around. Matt and I agree to shut up. Merlin, go for it. So, so plants photosynthesize, fungi don't photosynthesize and have to find food and digest it. And so what are they eating? What is the food? Well, they can eat many things. They're the great decomposers of the planet. They underwrite much of the regenerative capacity

of the biosphere because of their voracious appetites. So wood, for example, if fungi didn't decompose wood, then the earth would be piled kilometers deep in unrotted forests. But they can also eat all sorts of unusual things. There's a specialist mold that lives in Canadian distilleries off the vapors evaporating from whiskey barrels as they age. There's a fungus called the kerosene fungus, which lives in the fuel tanks of aircraft. So they have a wide variety of different appetites.

Wow. If they wanted to, they could just be our overlords from what you're describing here. Yeah, totally. Or underlords. Well, that does connect a bit to Lo Ruzzi's question. It starts with very nice things, saying big fans of the show. And then asks,

mushrooms are not only very resilient to extreme conditions, they also have the ability to spread even when they're technically inactive and to thrive when conditions become bearable again. In that respect, do we know if mushroom spores can survive the vacuum of space? And if yes, can we imagine them seeding distant planets and making a better job of surviving than the human race? So fungal spores are really tough, and some of them can survive these um extraterrestrial

conditions and other types of fungal organism can too lichens which are a symbiotic organism a combination of fungi and bacteria and algae they can and they're some of the hardiest organisms known and when they're taken to extraterrestrial conditions they're suspended on the outside of the international space station in trays known as the expose facility but they're they dry out very quickly of course in the vacuum of space but then they can withstand the radiation and the temperature swings and when you bring them back to earth they rehydrate and get on with living and so there are different aspects of the fungal kingdom, different parts of the fungal kingdom

that can withstand these extreme conditions. So they don't need spacesuits, is what you're telling us? No. Actually, I didn't know the space station had sort of an outdoor tray for the vacuum of space experiment lab. I didn't know that. Well, they've also tested them in the Mars simulation facility

where you can just put them in a box and turn on Mars and you can just dial up or dial down the radiation to test them to their uttermost limits of survival. Pretty useful. Man, I have a whole new respect for mushrooms now. Damn. Okay, Matt, keep them coming. Okay, so Alec asks, Alec from the Oregon coast says,

hi from there and hope we're all doing well. And how long have fungi been on the earth? And does that give a glimpse into what prehistoric animals might have eaten? So, general consensus from fossils and from looking at the dna is that fungi have been around for just over a billion years but mysterious fossils bearing an uncanny resemblance to mycelial fungi have been found in lava deposits dating from over two billion years ago and it's not clear whether they were true fungi or not, but they certainly look like fungi.

And if they were fungi, it would totally upend everything that's thought about the history of multicellular life. And so, but do you think mushrooms would have been a part of early animal diets? Oh, yeah, for sure. I mean, I don't see why animals would neglect these nutritious, delicious organisms growing within easy reach. Would an animal knowingly, an animal not human, knowingly eat a mushroom that has psychedelic properties?

It's a very good question. I was talking to Michael Bug, who runs the toxicology reports for the North American Mycological Association. And he has a number of reports of dogs that watch their owners picking psychedelic mushrooms

and after watching them would also eat the psychedelic mushrooms and would appear to be under the influence. There's only one example of a cat that repeatedly ate its owner's psychedelic mushrooms and appeared to be bemushroomed in his words.

See, I think cats are always eating mushrooms based on the behavior patterns that I've seen. I have no idea how you would tell my cat whether he's taken any. That's what I'm saying. Before we go to break, let me just understand this. The pronunciation of the plural of fungus, I've heard fungi and fungi.

How do the Italians say it? The Italians say fungi. Fungi. I say fungi, but people say fungi, people say fungi. It's really up to you. Oh, okay. I'm glad to hear that because I think I've said at least three different versions

in the course of just the last 15 minutes. So I will do as the Romans do and call it a fungi. Is that correct? Fungi. That's what I'll do. I don't know about Matt. I don't know where his allegiances are found

but I'm going with fungi. And just before we cut here, I just want to finish out some of your resume. It's interesting here, you're on the board of, the advisory board of the Fungi Foundation. That's great. That just sounds like, is that on a business card? You know, advisor to the fungis.

You know, it just sounds so so otherworldly if you will and the society for the protection of underground networks what do you do there prevent people from putting pesticides or something or herbicides i didn't know the underground networks needed a lobby you know lobbyists yeah well part of it's just mapping the mapping the networks around the world um what type of fungal networks and fungal networks interacting with bacterial species and plant species do you find in different places? Because obviously we can't know what damage we're doing

until we know what's there. But it's very clear that we will be damaging these networks. But it doesn't feel like they care about, well, I mean, not speak for them, for the mushrooms. Let me just say broadly, if they are all over the place, then why should it matter to us if we dig up some ground over here and not over there? I mean, what is it you're actually trying to protect? So many fungal networks enable plant life.

Plant life would be inconceivable without the fungi that live in their roots, without the fungi that live in their leaves and in their shoots. In fact, plants wouldn't have evolved if it hadn't been for their relationships with fungi. So if we depend, say, on an ecosystem, a forest, for various reasons, and we kill all the fungi in that forest, then we're making trouble for ourselves and for everyone else who lives in the forest. So there are lots of reasons to, so some fungi are able to withstand intense conditions, but many fungi aren't. And so it's for these fungi that we need to be mindful.

Got it, got it. Okay, and that's part, this is the perennial challenge of anything we do to the environment because one thing depends on another, depends on another, and ultimately comes back to bite us in the ass right so exactly and the most worrying worrying things are the unknown unknowns and there's so much of fungal life we don't understand

there's so much of microbial life we don't understand um and so we're in a kind of a race to to just to get a picture of what everyone's doing so that we can avoid making even more catastrophic mistakes than we have. That's why we have you. Okay. So let's take a break here. And when we come back, we're going to find out more of what our fan base

wants to know about mushrooms, their psychedelic properties, and anything else that mushrooms have been hiding from us for a billion years on StarTalk. Hey, I'm Roy Hill Percival, and I support StarTalk on Patreon. Bringing the universe down to Earth, this is StarTalk with Neil deGrasse Tyson. queries. We're talking about mushrooms. Everything you ever wanted and never wanted to know about them. It's going to happen in this show. I got with me my co-host Matt Kirshen. Matt, what's your social media handle

that you want to put out there? Oh, at Matt Kirshen on Twitter and Matt underscore Kirshen on Instagram, but I very rarely use that. Twitter's the one to look at. Okay, Kirshen, K-I-R-S-H-E-N. But if you're not sure, just bang anything close to that into Google and it'll find me. That's very confident of you.

There just aren't many of us. There's very few Matt Kirshens in the world of any spelling. You and Google go way back, I get it. So for this mushroom expertise, we've got Merlin Sheldrake, who's got a book out just now in paperback, Entangled Life, How Fungi Make Our Worlds Change Our Minds and Shape Our Futures. This is an audacious title. I'm loving every minute of it.

So Merlin, great to have you. Are you active on social media as well? I think I saw you have a Twitter handle, Merlin Sheldrake. Yeah, and Instagram, Merlin Sheldrake. And Instagram, yeah. There's no other Merlin Sheldrakes in the world. You're the only Merlin I know in the world. Did your parents have very high expectations for you?

You know, I'm not sure. They said that they were calling me Merlin after the bird, not after the wizard. But I complained that I didn't think they can really make that kind of distinction. So let's pick it up. We're in the middle of our flow of questions. And these are all Patreon members.

We used to only lead off with Patreon questions, and now they own the whole stash. So every one of these is from Patreon members. I just want to publicly thank them for their support. It enables us to do experiments that might not otherwise be commercial. And thank you for that. It keeps us going. Yeah, and there's some great questions that have

come in from the patrons, including a couple of people have asked about this phenomenon of fungi taking over other animals. So Zach Metcalf says, some species of, I hope I'm pronouncing this one correctly, is it cordyceps fungi,

can infect insect hosts and compel them to die in very specific locations. Famous examples are infected bullet ants climbing trees and dying on the undersides of leaves, the ideal location for spores to rot from their skin and infect more ants below. How do the fungi relay such specific instructions to its insect victims? Is the electrochemistry of walking and climbing really so straightforward as to be hijacked by fungus. Man, and they sound like, they sound evil.

Yeah, I mean, that is quite a remarkable thing to do. This is an evil set of species you got here, Merlin. All right, so what's going on there? Yeah, so first, I wouldn't underestimate the metabolic abilities of fungi. So they're metabolic wizards and can do all sorts of extraordinary things. So even if it was a complicated task to hijack an insect and control its behavior with a great deal of precision, which no doubt it is, I wouldn't put that past them.

And we don't need to try it because we know that this takes place. But broadly speaking, I mean, the degree of precision is remarkable. So you can have, for example, a carpenter ant and an Ophiocordyceps fungus, and the fungus will grow into the ant, start growing its way through its body, through its legs, through its cavities. It won't grow into its brain, though,

which is interesting. And then it produces, whatever it does, it produces in the ant an irresistible urge to climb upwards, overriding the normal instinct of the ant, which is to stay close to the ground for purposes of safety. So the ant climbs up in a syndrome known as summit disease, and then it finds at the nearest vein on the underside of a leaf, at exactly the right height for the fungus to fruit, in the case of Ophiocordyceps and carpenter

ants, about 25 centimeters off the floor of the forest and then around noon the ant performs a death grip and it grips onto the leaf vein um the ophiocordyceps has um has special needs and um and then the fungus kills the ant and it grows a stalk out of the ant's head and rains down spores on unfortunate ants passing below. It grows out of its head? Mm-hmm. Yeah, I mean... Man, so the movie Alien has nothing on this, really, because that's just coming out of your belly. That's the normal place you might find something growing inside of you.

But it grows out of its head. Well, there are lots of different ways. Lots of different fungi do it differently. There's fungi that infect cicadas, and it causes the back third of the cicada's body to break off and for the male cicadas to become hypersexual, despite the fact that their genitals have long since crumbled away. And the cicada

spouts spores from this broken back end of its body as it flies around erratically. Well, we're in a cicada invasion now in the northeast of the United States. You surely know that. I committed online that I said I would eat three of them when they finally came my way. So you might want to watch out because the macospora, the fungi that overtake these cicadas,

and no doubt that we're doing it right outside your house, they produce psilocybin and also amphetamine. So if you eat enough of them, then you might start feeling stranger than you realized. Okay, and I might have accredited the cicada, but it was really the invading mushroom spores that would have done it to me. That is astonishing.

That's a good heads up there. Thank you. You'd probably need to eat quite a few before you noticed that. I think you'd be safe with three. Yeah, that's not happening. No risk of me eating any more than I committed. So Matt, keep them coming. Well, a related question from Teresina who asked earlier was,

is it possible for a fungi to take over a control of a relatively large animal? And to what extent do they influence our own behavior? Yeah, how about mammals, like small mammals, like, you know, under scurrying mice and things, you know, field mice, that sort of thing. So these fungi that take over insects with this great precision, none of them are known to take over animals, mammals. Mammals are a bit trickier because we have a higher body temperature, which tends to put off fungi, doesn't always put them off. And there are a number of fungi that can cause a big problem in an animal body,

in a human body. But there aren't any examples of quite such specific alterations. There are fungi that will infect you and cause a life-threatening disease and make you feel strange and will change your behavior because it's made you sick,

but not that will grow inside you and puppet your behavior with the same degree of precision. Or make you climb up a tree and scatter spores out of your abdomen. So when I was doing that, I can't blame that on any kind of fungi. You did that. Yep, you got to own that one, Matt.

That's all you. So I got one for you. And I want to pretend I'm a Patreon member now. So if you ever get what they call athlete's feet, the cure for that is antifungal cream. So are you telling me if I have athlete's feet, I have fungus growing in my toes? That's right.

On your toes more than in your toes. And it's one of these things you study. This is your fault. You, your species, your families of species are giving me athlete's feet. That's what you're saying. Neil, I mean, your subject matter wiped out the dinosaurs in big cataclysmic events.

Okay, you got me there. You got me there. I got no comeback on that. Okay, we have an asteroid the size of Mount Everest that took out a whole 70% of Earth's species. Okay. All right. I take it back.

But that is a kind of mushroom is what you're saying. It's a fungus. It doesn't produce mushrooms, but it is a fungus. Oh, sorry. Mushroom is the fruit, but it's a fungus. I got you. Damn. So Gordon, Patreon Gordon Vu asks something related.

It says, I suffered from jock itch, which I believe is the same, I think that's the same fungus. And the doctor said it was a fungal infection. Does this fungus grow elsewhere besides the human body? You know, I'm not totally sure. This is too much information about this guy's hygiene. Do we really have to find out?

He puts out his name, and he's telling the world he's got jock itch. It's all science. Okay. It's for science. Very good. Okay. We have a devoted following.

He didn't even say, I have a friend who has jock itch. He didn't even say that. I think that's worse, though. I think if you know about your friend's jock itch. That's a good point. What the hell are you doing know about your friend's jock itch that's a good point what the hell are you doing knowing about your friend's jock itch okay so so is that is it the same species because what's interesting merlin i learned is that head lice is a different subspecies of lice than um a genital lice so i couldn't tell you whether they're the same.

I suspect that they're slightly different. And I couldn't tell you whether or not it lives in other places. But it's very common for fungi to be able to live in different situations. If you have an oyster mushroom, mycelium, that would grow on a book. That would grow on used cigarette butts. If your nutrient isn't the right way, it could grow on grains. It could grow on logs of wood. So many fungi have Catholic tastes,

and it's possible, though I can't say for sure because I don't know, that the jock itch species also lives in other places when there are no jocks. You give it no reason to think they'd be different. Right, right, given. I think it was an oyster mushroom that was growing out of our carpet

after a week or so after the toilet was broken at the party. Would that be plausible? It certainly looked oyster-like. It was a surprisingly large mushroom that had appeared in our house in a place that it shouldn't have appeared in, in this gross place that I lived back in my early 20s. Matt, when you climbed the tree, you spored out the oyster mushroom. We shouldn't have put the tree in the toilet either.

That was another mistake. That's the first giveaway right there. All right, Matt, give me some more. Well, so Gordon goes on to actually ask, I'm curious if there are telltale signs to differentiate between an edible and poisoned mushroom, and why are some mushrooms poisonous and others not? That's a good question.

You know, because, Matt, I mean, why? I mean, if, if, if, I mean, a mushroom is a mushroom, I guess maybe a mushroom is just not a mushroom. They're all different. That's always been, you know, I've, I've been curious about that because I know there are people, you know, mushroom foraging is a big thing. People foraging for, for cooking reasons. And then also people who are foraging for more party reasons. But in either case, the, the, the warning has always been, well, you better make sure you know what you're getting because if you pick up the wrong one,

then you can be in some real trouble. Right. So we have healthy, poisonous, and psychedelic. So how does the mushroom kingdom divide up? Well, some mushrooms will kill you. So you definitely need to know your mushrooms if you're planning to eat them. But there's no... But at least they won't kill me

by having something grow out of my head. It's just a regular old poison. I'd rather that than be humiliated by having spores come out of my head. I'm sorry. Well, they're pretty deft. Some of them you will eat them, the deadly poisonous ones you might eat them,

you'll feel pretty bad for a while, then you'll get better. And then a day or so later, you'll drop dead. It's called a false remission. So they do have their methods. But there's no reliable trait that you can use to distinguish poisonous from non-poisonous across the board because lots of the poisonous ones

are poisonous in different ways often. And some of them, it's not clear a professor um a professor of history of science i used to go out mushroom hunting with he had a big collection of mycological texts and i asked him wait matt did you hear that i had a professor that i once went out okay this is did the professor give you a bad grade and we don't have the professor anymore in the world? Well, I mean... We can't with your past tense around us here. I don't know what you got going there, but go on. Sorry to interrupt.

So what he said was that... I said, are there cases where the same mushroom species is described by different books in radically different ways? And he said that there was a book, a German guidebook, 100 years old or so, that he had. And it described the yellow staining mushroom, which in English guidebooks says poisonous, don't eat, skull and crossbones, stay clear.

In this German guidebook, it said delicious when fried lightly, but might cause a light coma in those of weak constitution. Mild coma. I know, light coma it sounds quite fun doesn't it but um not a heavy one just a light one and and it turns out that it depends on your metabolism some people have the ability to to metabolize these toxins other people don't so even if you can tell what mushroom you're eating in rare cases um ill people will have different reactions to that very same mushroom. It's a bit like plants, you know. There are plants that will kill you. Some plants are delicious.

Some plants people can tolerate. Or some people are allergic to tomatoes, you know, that sort of thing, I guess. You know, okay. But that'd be, I guess it's all chemical at the end of the day. But it's not a living thing that's attacking you for having consumed it. All right. I mean, in other words, a poisonous mushroom and you dying from eating peanuts because you have a peanut allergy,

these are different causes, correct? Yeah, because the peanuts won't kill everyone, but a poisonous mushroom would kill everyone. Yeah, an authentically poisonous mushroom. If you ate sufficient quantity, yeah. Yeah, yeah, all right. All right, Matt, we've got time for one more before we hit a break

and then come to our final segment. So what do you have? So Isaac Lambert asks, how much faster is mycelium in plants, fungi, and trees than the neurons in our brain? I didn't even know that they were faster than the neurons in our brain. Oh, oh.

I mean, is a neurological analog sensible here? I mean, is a neurological analog sensible here? So some fungi produce waves of electrical activity analogous to the impulses that travel in our nerves, which is a fascinating finding, which might really shake up the way we think about the communication that fungi can conduct and the way that they connect other organisms together. And so given that some fungi do produce impulses,

electrical impulses, then when you look at it, you have our nervous systems, which contain long, electrically excitable cells, and you have fungal networks, which are networks of long, electrically excitable cells. And on a superficial level, there are some similarities. The neurons in our bodies conduct impulses or action potentials

very much faster than those that you find in some fungal networks. Because remember, not all fungi do this, only some do. So there's a big difference in speed. But then again, we have a need for much faster speeds. We live at a faster pace because we're locomoting, we're moving, we're twitching muscular bodies. So we need that speed, but the fungi may do perfectly well without that speed.

Because we live in the fast lane compared with mushrooms. That's not going to think about that. All right, slip one more in, Matt, before we hit the break. Teresina asks, are there any naturally occurring networks of bioluminescent fungi? In fact, I was just notified we have to take the break, but let's hold on to that. And I think they call that a tease. Is that right?

Bioluminescent chemical pathways. When we return from this break on StarTalk, Cosmic Fairy, all about mushrooms. Hey, it's time to give a Patreon shout-out to the following Patreon patrons, Elliot Frost, Vincent Krohn, and Susanna Lobo. Guys, thank you for all of your support. You know we couldn't do it without you. And for those of you listening who would like your very own Patreon shout-out,

go to patreon.com slash startalkradio and support us. We're back. I got Merlin Sheldrake, the world's experts in mushrooms. And he did that on purpose, like got his PhD and studied it and everything. And so that makes him really useful to people who have their own relationship with mushrooms. And Matt, apparently you grew mushrooms in your toilet. And that's all I really want to know about that. Any mushroom cultivation in my life has been entirely unintentional.

Unintentional. Okay. So what's that last question you had about bioluminescence? So are there naturally occurring bioluminescent fungi? So are there naturally occurring bioluminescent fungi? Yes, is the answer. There are a number of species of bioluminescent fungi. Some produce mushrooms that bioluminesce, and some produce mycelium bioluminescence, like bioluminesces. In fact, the first ever submarine called the Turtle, which was invented during the American Revolutionary War,

a fungally bioluminescing bits of wood were used to illuminate the depth gauge of the turtle, known as foxfire, this particular instrument. Wow. Whoa. So we knew about that and how to then exploit it. So we, early on, you're saying we weaponized bioluminescent mushrooms.

Well, I don't know how effective the turtle was. Nonetheless, we weaponized bioluminescent mushrooms. Well, I don't know how effective the turtle was. Nonetheless, we weaponized it. I don't know if that's what did it did off with the British. Wow. Okay. Very cool. And by the way, this all sounds like

the tree of life mapping for James Cameron's movie for Avatar. He's trying to come up with exotic life, and he gets all the most exotic life on Earth and makes that the regular life over there, except they have USB ponytails where they can connect and talk to the animals.

The mushrooms have that too? I just want to know how quickly they will in fact become our reward. They do seem to be much more versatile than I had any idea about before we started this episode. Exactly. Yeah, well, they do. They grow into plants and they kind of plug in, if you want to use the electronics metaphor.

But the plugging in involves growing into a plant root, growing in and around plant cells. It's a very intimate embrace. And I guess you can think about that in an analogous term to the way that the plugging in happens in Avatar. The networks in Avatar are based on the fungal networks in the real world, of course. Scientifically, right. Because James Cameron, he has many movies, including The Abyss, movies where he has cared about the science of what surrounds his storytelling. And then he puts it in as best as he's able.

So keep it coming, Matt. All right. Well, Chaz Gencarelli, I hope I'm pronouncing your name at least vaguely closer correctly, asks, why are there so many different types of fungi still being discovered each year? Was that right? You guys are not on top of everything? No, so there's an estimated two to three million species of fungi on the planet,

and only about 150,000 have been described, and that means that six to eight percent of the total number of fungal species on the planet have been described, and that obviously leaves over 90 percent undescribed. So it's a lot of work for fungal taxonomists to do, just very basic descriptive work that hasn't been done for a

number of reasons. And one of the reasons is because fungi were thought to be plants for a very long time. And so they didn't get a kingdom's worth of attention from biologists. Another reason is that they live hidden lives. They live as mycelial networks, which are buried in whatever they're eating. Mycelium is how fungi feed. So they've got to insinuate themselves within their food to digest it. And what that means is that usually

we don't see so much of what they're doing. So it's harder for us to access. See, they're doing that on purpose. They don't want you describing them. I have the privilege of having a species named after me, a species of frog. And so I looked at the specie paper, the paper that makes up the species, and I was astonished how much measurement went on. You know, the ratios of the digits in the feet of the frog versus the pans and eye separation,

all of this gets characterized. And I'm thinking, damn, that must have taken a long time. And if you've got like a gazillion species left, I'm not doing it. I'm getting somebody else to do it. And there's only so many TV scientists, so how are you going to even come up with all the names? Exactly, exactly.

So it's Indirani tisoni, a species of leaping frog. And so I was very honored by that. Wow. You know, Linnaeus and the taxonomist, and Buffon, the French taxonomist, has a big rivalry, and both would name glamorous species

after their patrons, and they would name unglamorous species after each other, because they hated each other. The bullfrog was Buffo Buffo, because Linnaeus thought that he'd get one over on Buffon. Wow.

So the question is, Neil, is your frog, is it a glamorous frog, or is it an unglamorous frog? And if so... Well, I was just happy that it was a vertebrate, you know? There are like bugs and stuff and slime mold and bacteria. I'm sure those are wanting for names, but at least I got a vertebrate.

I'm just putting it out there right now. I would be honored to have a slime named after me. If there's any slime scientists there, I'll take any species of any kingdom. Okay. It's noted. The request is out in the mycelium. We'll see who comes back on it. All right, so Matt.

So I've saved these two towards the end because I think they're connected and they're a big topic that I think a lot of people are interested in when we talk about mushrooms and particularly talk about magic mushrooms. So Bo Shanker asks, is Merlin familiar with Terence McKenna

and his views on magic mushrooms? Could magic mushrooms have expanded the human mind, introducing complex language and culture to early humans through psychedelic experience? And then Robert Slosser asks, how much of an impact would you speculate has psilocybin had on human evolution? I think they're playing in similar worlds.

So I jammed those two together. Interesting. Yeah. So it's a great question without a clear answer. It's very hard to know one way or another when we're going back into deep prehistory. I mean, it seems clear to me that psychedelics, including psychedelic mushrooms, have had a very big impact on human culture and for an unknowably long time. And of course, culture and nature are categories that we create,

but they aren't separated by an unbreachable divide. Anthropogenic climate change is a good example of how cultural developments in humans can affect what we think of as the natural world out there. Terence's claim, Terence McKenna's claim, with the stoned ape hypothesis, was that eating magic mushrooms had caused human brains to increase in size. Or primate brains. Yeah, pre-human brains. This is a big claim. It's unlikely we'll know either way.

There's certainly something to be explained. So between 3 million years ago and 200 000 years ago when when we're informed that what we think that um homo sapiens first arose the primate brains that led to us increased by four times so quadrupled in size they grew to four times the size that they had grown in the previous 60 million years of primate evolution. This is sometimes called the brain boom. And it's known this took place. The fossil record is clear.

The question is why? There are a number of hypotheses. The brain is a really hungry organ. It makes up 2% of our body mass, but takes 20% of our energy at rest. So I think one of the persuasive hypotheses is that the domestication of fire helped because once you can cook food, then we have to eat less of it. We have to spend less time foraging. We can supply more energy to a hungry organ like the brain. Terence said that this was brought about by the mushrooms. Maybe, maybe a little bit, maybe some, maybe not. I mean,

psilocybin has been shown to increase nerve branching in dishes in culture, but that doesn't necessarily suggest that it would increase brain size over time in real life humans. There are different versions of the stoned ape hypothesis. Some of them suggest that big developments like symbolic language and other major milestones in human cognition arose through psychedelics. I think that's more plausible than the brain increase argument. I don't understand. If it's a temporary condition put on your brain chemistry, how does that make any kind of biological evolution at all? So Terence isn't here to defend it, but what he might say would be that there are epigenetic

shifts that would be carried over, or that there are cultural changes which then go on to increase our brain size. So you can imagine a hypothetical situation where someone took magic mushrooms, had the idea to domesticate fire, domesticated fire, had cooked food, and then that allowed our brains to increase in size. So it's very... You're saying this chemical can give you brilliant ideas?

Because from what I understand, the brain is pretty... It barely works as it does, right? Now you're going to toss in some extra chemicals that will alter your perception of reality. And you want to claim that you're now closer to nature. So just, sorry to jump in, is the claim kind of just, I'm trying to untangle it, but the claim isn't that the mushrooms themselves grow the brain, but the mushrooms expand your horizons that make you then think of doing things that then down the line cause your brain to increase in size. So there are different versions

of the stand-up. And so some of them would say that the mushrooms themselves cause an increase in nerve growth, and that somehow passed on intergenerationally. And some of them, I think the more plausible ones would say that the experience, the radically altered cognitive experience, the uncon altered cognitive experience, the unconstrained style of cognition that you have when under the influence of mushrooms, gives you new ideas and invites you to behave in new ways. Possibly synesthetic ways,

which might give rise to certain new ways of using language or sounds and associating those with meanings, for example. Has that happened to you? I have taken a second... In other words, have you had a deep thought. Has that happened to you? I have taken... In other words, have you had a deep thought that you're pretty sure you wouldn't have had had you not exposed yourself to psychedelic mushrooms? Yes, in a word.

Yes. So you'd recommend everyone do it then? No, I wouldn't do that. Why? If it made you smarter or more insightful in your own work, why not just have it over the counter at the pharmacy? Well, these experiences can be somewhat unruly. And so you'd want to be sure that you're taking it in the right frame of mind, in the right setting. And some people might have constitutions that would not agree with this kind of

radical alteration in their experience, and it'd be wise to stay clear. Other people might have constitutions that would not agree with this kind of radical alteration in their experience, and it'd be wise to stay clear. Other people might need certain kinds of supervision. It's not a straightforward process. So I wouldn't recommend that everyone took them. I think many people can certainly benefit from psychedelic experiences, which is why it's exciting to see this new wave of research into psychedelic compounds pick up steam. I get it.

Well, this isn't one of the Patreon questions, but I know there's been quite a bit of research recently. There's been a fair few news stories that have come out of late into how psychedelic treatments might be beneficial for certain types of depression. Yeah, I've seen more articles on that. That's right. So it's one thing to know that it's there and it's psychedelic, but it's quite a whole other exercise to take this chemical and see how it can be absorbed, uptook into civilization in ways that can serve our needs. Yeah, I mean, the thing to remember is that these psychedelic compounds, whether from fungi or from plants or from animals, they've been really major parts of traditional human societies for a very, very long time.

And so it's not like this is news in the big picture of human existence. It's just this new way that science is finding to describe, quantify, and make sense of these experiences within the framework of modern medical pathology, modern illnesses and treatment programs. All right, give me another question. One final question then, because this is, Teresina sent in a bunch, and this is the last question that we have. And this is, how can we take advantage of the properties of the fungi network to combat climate change? And can we even? Is possibly a bigger question. Yeah, if the field is in its infancy in a way,

there could be so much potential if people are thinking the right way about it. Or you bring people from other disciplines to then help explore what applications might exist that would be invisible to someone who's really close to the problem. Yeah, there's an explosion of interest in fungal applications at the moment, and many of them to do with the ways that fungi can help us adapt to the climate change problem, or problems rather.

So there are a number of ways you can think about it. There are fungal medicines that can help humans recover from illnesses, but also can help other animals. The mycologist Paul Stamets has done some amazing work showing that fungal extracts can help bees overcome viral pathogens and so extend the lifetime of bees and beehives, which in turn can help us adapt to changing climates and changing pressures on pollination schemes.

There are also fungal materials built using mycelium, which can help disrupt polluting plastics industries, can create sustainable materials for use in buildings or structures, but also for clothing and kind of leather-like material. Fungi in agriculture and forestry, we're never going to not need to grow trees and plants and fungi are fundamental to all plant life so other ways that we can change our behavior so that the plants and fungi can better support each other in these changing situations we find ourselves in. There are fungal foods, other new types of ways that we can grow proteinaceous, delicious meat substitutes using mycelium, which would relieve our dependence on

unsustainable meat farming. There are many such examples. There are also ways that climate change might make things worse in conjunction with the fungi. So some fungal pathogens of plants, for example, might be able to move into new areas when climates change, and whole swathes of forest might become vulnerable to new fungal pathogens. It's already happening. Killing off huge areas of forest, which would then be decomposed by other types of fungi, and lots of CO2 will then be emitted into the atmosphere.

So it's not a straightforward story about fungal saviors. Fungi are startlingly ingenious opportunists and as things change they will be able to move into new niches and maybe sometimes that will be good for us and sometimes less good. Do you have any parting thoughts for us about as we go forward? Do you have any parting thoughts for us as we go forward? Any advice, any bits of wisdom that you have gleaned from this mycelial madness? Well, you know, Neil, one thing I've often thought about, because these fungal networks are astonishing and raise all sorts of questions about how life works.

But one of the things that's been interesting recently, maybe you'll be able to tell me a bit more about it, is that the cosmic web, the very structure of the universe, is now thought to be made up of big filaments of gas and galaxies arranged in clusters linked together in this way. So I would say, as below, so above, when I'm looking at these fungal networks and thinking about the structure of the universe.

Presumably, you would say, as above, so below. Well, okay, I'm happy to say that they look alike, the cosmic web that they speak of, but a web implies some coherence to what's going on. And in this cosmic web, the distances between nodes is so far that even at the speed of light, an appreciable fraction of the age of the universe has to go by before it could communicate with another.

If you want to use the word communicate. So we have galaxy clusters that are so large that they're clearly together, but it can take the age of the universe for any one galaxy to cross and get to the other side. Well, that's really that's the slow boat all right so it's not authentic it's not legitimate to think of these as functioning systems if if we're limited by the speed of light of course as we expect that they are whereas your

mycelium and everything else that's sort of terrestrial or smaller, yeah, you can have interconnectivity on the timescale of the lifespan of the organism you're talking about. So just because things look the same doesn't always mean they are the same. And I would say in this case, that's one of those examples. Yeah, I mean, I didn't think for a moment that the cosmic web and the oyster mushroom mycelium were the same. It would be cool if they were,

if the mushrooms, in fact, were communicating with the galaxies. So Matt, we just give up at that point. We've got no hope as humans in this universe the day we discover that mushrooms are controlling galaxies. All right, guys, we've got to call it quits there. So Merlin, thank you for coming on to StarTalk all the way from London. And we're going to follow your work. And just in case you discover some new mushroom

and you want to tell everybody about it, you can do it here first. We've got some new fancy mushrooms, got new properties. We'll take that interview. And Matt, always good to have you. Oh, it's good to be here. And I'm fascinated. I want to know more about, I'm getting this book because I feel like we've not even scratched the surface. No, of course not. Of course not. Right. It's not possible for something that complex. All right. So Merlin, when the mushrooms become our overlords, I think, see, Matt, I think he's practicing for that

so that he won't get... I think they might already have. They'll keep him as their pet, and they'll eat the rest of us. You see, that's how that works. I think they've already infected me, which is why I'm here talking to you. All right, we'll close it out there.

This has been StarTalk, and I'm Neil deGrasse Tyson. As always, bidding you to keep looking up.