Selects: Slime Mold: 0% Mold, 100% Amazing | STUFF YOU SHOULD KNOW

Hey there everybody, it's Josh and for. this week's select, I've chosen our June. of 2021 episode on slime mold. It's. actually a powerhouse episode and it's. filled with maybe more amazing facts. than any other episode we've ever. recorded. It's just like mindb blow. after mind blow after mind blow. So. strap on your old timey football helmet. and prepare for slime molds. I really. think you're going to enjoy it.

Welcome to Stuff You Should Know, a. production of iHeart Radio. Hey, and welcome to the podcast. I'm. Josh Clark. There's Charles W. uh Chuck. Wayne Bryant. And uh this is Stuff You Should Know. No. Producer Edition. >> That's right. >> It's just just us, buddy. We're going to. do it. We're going to be just fine.

>> Jerry took an early vacation for. Memorial Day. >> I know. She's always doing stuff like. that. She knows how to live. >> And we're stuck with slime mold in her. absence. >> I like slime mold. >> I knew you would love slime mold. >> Uh yeah, I think it's pretty interesting. stuff. >> It's very Josh Clarky. >> It is kind of Josh Clarky. So much so. that um as I was researching this like I. mean I just kind of generally knew about. slime mold that it exhibited you know. some weird level of intelligence here or.

there but I didn't know much about it. And then as I was researching it I was. like I'm kind of into slime mold now. Yeah. >> Like all the different kinds of it. I. like regressed into like you know the. nerdy 8-year-old I never was. >> Yeah. And then you were like let me. clark this over to Chuck and see what he. thinks. >> Yes. >> Uh yeah. I like slime too. I think it's. kind of cool. Uh, let's do it. >> Okay, Chuck, >> I'm ready. >> All right, everybody, stand back cuz we. are doing it. >> Yeah. And I think you could file this. I. mean, it's not an animal slime mold. I.

guess we should just tell you right away. it's not an animal. It's not a fungus, even though you would think it's a. fungus if you saw it on the forest. floor. And we'll get to all this stuff, >> but uh. it feels like an animal, one of our. animal episodes anyway. Sort of. >> Yeah. I was going to save the fact that. it's not an animal or fungus for the. very end, but sure, we could do it at. the beginning, I guess. >> You mean like literally in the last. minute they were like, I still don't. know if this is an animal. Is it a is it. a dog in disguise? >> You know, everything we just told you.

about, it's not an animal. It's not even. a fungus. And then we just go to. listener mail. >> Uh, so what is it though besides super. ancient as in like maybe one of the very. first living things? >> Well, it's a prous actually. they. figured out and protests seems to be. well it's one of the five main kingdoms. animal uh bacteria plants fungi and then. protests and protests are typically. single-sellled organisms like amoeba um. or protozoneans things like that and.

they have I don't I couldn't find out. exactly when they did it but they fairly. recently I guess in the history of. biology fairly recently. reclassified slime molds from the. kingdom fungi over to the kingdom. protista. >> Yeah. Which is interesting because for. years they had been studied by. micologists who were fun fun guys. >> Yeah. >> And they found out later they were like. you know what sorry this should really. go over to the protologologists.

and they said we kind of like these. guys. Can we keep studying them since we. have been? >> And they said sure and the protologists. were super pissed. >> They were they were they're still. actually not over it. They're frequently. tepeeing the academic halls of the. micologists whenever they get the. chance. >> Yeah, it's just very bitter battle. >> So, um that is pretty cute that they're. that the the fungi people are still are. still studying slime molds even though. they're not fungi. But, um there's, you. know, some good reasons why they.

originally considered to be fungi. Mostly that they're like these big kind. of clumps and there's all sorts of. different ways that they take shape and. form depending on the species. They're. different colors. Some of them form kind. of net-like honeycomb structures. Some. of them look like dog barf. One of the. main ones we'll talk about today looks a. lot like dog barf. >> Um. >> they look like a fungus though. Like if. you were walking in the woods and you. saw this, >> nine out of 10 people would say, "Well, it's got to be some kind of fungus.". >> Yeah. Especially because if you're.

staring at them, you would have to stare. at them for about 5 6 10 hours. >> to see that they have a huge difference. between uh them and fungi and that they. move. >> They just move so slowly it's not. apparent to the to the naked eye. But if. you if you film these things with. time-lapse cameras uh and speed it up, you can see, oh, they very clearly move. about from place to place. So, um, that's a big differentiator between them. and fungi. But one of the reasons they.

thought they were like fungi, that they. were fungi, is because they produce. spores to reproduce, >> right? And I mentioned their ancient. origins. Uh, they are. >> about a billion years old. And like I. said, could be like as soon as there was. stuff, it seems like there was slime. mold. >> eating eating the bacteria that breaks. down other stuff that dies. And that's. what they they feed on. bacteria, mold, yeast, basically anything that. decomposes dead things. Slime molds.

engulf. Uh I think it's it's not called. photography. It's called fagotrophy. >> Oh, yeah. >> It's a little. >> That's not how I was going to say it, but. >> what were you going to say? FGO trophy. trophy. Yeah, but I think you're. absolutely right. >> Well, you know us. It wouldn't be us if. we didn't probably both get it wrong, >> right? But uh that's when you basically. surround something and engulf it and. just sort of like move it into your body. just like sort of absorb it basically.

>> Yeah. Which is another difference. between slime molds and fungi because. fungi actually break the food down and. then absorb the broken down nutrients. But the fact is, if you have things that. are decomposing other things like. bacteria, molds, yeast, the things that. that crawl onto or grow on dead people, dead trees, all that stuff, break them. back down into their constituents. So, the fact that those the slime mold feeds. on other things, it makes it a really. important part of the the food web as. part of the nutrient cycle because other.

things come along and and eat the slime. molds. Um, there's apparently a kind of. beetle that has a specialized jaw that. allows it to slurp up slime molds. I. think some kinds of insect larvae eat. them. And then so it just kind of keeps. going. But there are really important. part where you just have these microbes. that like the beetle couldn't get to. that they're able to basically get that. energy from, you know, the bacteria by. eating the slime mold, >> right? And even though other protests.

can carry disease, slime mold is quite. human friendly actually. Uh you can eat. the stuff if you want. There's a dish in. Mexico and some parts of Mexico called. kaka duna which is exactly what you. think. It is. >> poop poop of the moon poop. >> Yep. >> And uh they they eat this stuff. I even. looked online to try and get a good. recipe, but um it it's not on like the. pages of Martha Stewart Living. like. it's you got to dive deep into Reddit. and stuff like that to get some good. recipes. It seems like.

>> almost almost smacks of urban legend, but I'm seeing it in different enough. forms. >> Yeah. >> That I think it's probable that it. actually is a thing. The thing that. scares me is that people say like in. some regions of Mexico, it's like that's. not super specific, you know? >> True. Uh and and we pointed out they. weren't animals or plants, but we. definitely need to point out that slime. mold is also not mold. >> No. >> As a protot. That's right. So, um one of.

the one of the really amazing things. about slime mold is um there's a couple. of different kinds as we'll talk about. in a second, but one a whole bunch of. different kinds of species. One type of. slime mold can get really big. I mean, some of them can get up to the size of. like a a medium or pizza, large pizza, I. guess, depending on whether you're. getting ripped off by your pizza guy, but like 12 inches in diameter. >> That's enormous, right? So, you're like, "Well, that's pretty cool. It's a big. blob of mold." Well, put your sock.

guarders on cuz I'm about to blow your. socks right off your feet. Some of those. types of slime mold that are as big as a. pizza are one giant cell. >> Yeah. I mean, this is truly amazing. the. plasmodial slime mold, which is I guess. you could call it one of the a true. slime mold. >> Mhm. >> Is it has all the stuff like as if it. were undergoing cellular division and. all the all the different nuclei like. millions of nuclei, organels, cytoplasm, all that stuff. But it's just not it.

doesn't have cell walls. It's not. individual little cells. It's just it. splits and lives inside this giant. fortress wall. >> Yeah. It's almost like if you took all. the cells that should have made this. giant blob um up as a multisellular. organism and just kind of broke them. open and dumped all the contents into. this blob. >> Yeah. >> And then threw the cell walls away. That's what you would have. >> It's super interesting. >> It is. And it's it's really kind of. straightforward if you if you just hear. it, but it's also really easy to to just. keep going like wait why why is it like.

that? And how is it like this? What's. going on here? Which is one of those. things that just it makes slime. It's. its own thing and we're still learning. about this stuff, you know, every day. >> Yeah. And it I mean it gets there's. quite a few times in here where we're. going to say and here's where it gets. even crazier. >> That's right. >> Uh this isn't super crazy, but the the. other kind of slime mold um or the other. big broad category is the cellular slime. mold. >> And these are lots of individual.

single-sellled organisms. But the kind. of knockout fact about them is when. they're stressed out, if they don't have. a lot of food around, they can. join up together and sort of look like. one of those plasmodial slime molds, but. it's not. It's called I guess. pseudopplasmodial. >> Yeah. >> Because it's not a real one, but it. basically says, "All right, we're going. to all come together to try and find. food together." And then when they do. have food, they can be like, "All right,

we'll just go along our merry way and. split up again.". >> Yeah. Which is pretty nuts. They also. will come together. Um, apparently it. makes it harder for predators like those. specialized beetles to eat them. >> because those individual slime molds can. be, you know, a millimeter uh in size or. smaller. Yeah. >> Um, so it's pretty easy for a beetle to. eat that. It's much harder for a beetle. to eat something the size of like, you. know, a quarter, right? So they actually. do come together. They come together to. move. They also come together to. reproduce and and produce spores. But.

the the characteristic of this that what. makes it a pseudopplasmodium rather than. actual true slime mold is that they. retain their cell walls, their. individual cells when they come. together. They just kind of loosely form. together. And a really good way of. understanding what this these cellular. slime molds create is kind of like a. swarm. >> Yeah, that's a good way to put it, I. think. or uh what's the uh God that my. favorite thing when the birds do that. What's that called? >> Uh flock of seagulls haircut.

>> Sure, that's it. Uh. uh boy, you threw me there. So these uh. the plasmodium is covered by a layer of. slime. And you're going to want to put a. pin in this because when they do move. around, >> they leave behind a little these little. collapsed tubules. And it it looks. basically like uh not exactly like a. snail trail, but sort of like a layer of. slime. >> And you're gonna want to remember that. for later on because these actually kind. of serve as important little markers.

>> As a matter of fact, write write it down. everybody. We'll wait until you get a. pen and piece of paper. >> Pull over. Go inside the CVS closest to. you. >> Yeah. Yeah. >> Put on your mask. Buy a pen. >> Yep. >> Buy a piece of paper. >> Pay 10, 12 times what you should have. paid for that pen. >> Really? Oh my god. The. >> pin markup is big at CVS. >> I think the general markup at CVS is. fairly high. >> Oh, they're like, "We get them in here. for the aspirin, then we really juice. them with this ballpoint pens.".

>> That's right. I hope there's no CVS ads. in this episode, but we'll find out. >> What is a What's a good deal at a a. drugstore? Is there like a I didn't. >> There's not There's zero. >> Oh, they all mark it up. >> Yeah, everything's marked up because. it's like a It's a convenience kind of. thing. A lot of. >> You sound like a grandfather. It's all. marked up, >> right? Back in my day, you just go to a. regular grocery store and buy your pens. normal price. >> from the bin factory straight from the. man who made it. >> That's right. >> Uh, you know, when I was little, we.

would uh for a short time, I'm not sure. why we did this cuz it's not like we. lived out in the country. And this is a. very old timey country thing to do. We. bought our milk direct from a farm. >> Nice. >> And we would pull up and and uh I would. get to walk inside this huge walk-in. cooler like next to a loading dock. And. I just thought it was like the coolest. thing in the world somehow to get that. fresh milk. >> Sure. Then they they back the cow up and. it make a beeping sound and they just. squirt the milk right into the back of. your station wagon. >> That's right. They mark it up first.

>> Slosh your way home. >> Uh so where were we? Okay. If you do see. this stuff in the woods, if you're ever. hiking along and you see a big or. mediumsiz pizza like yellow blob or. orange blob, they can be red, they can. be white, they can be maroon, very. rarely they can be black, blue or green. Uh but usually it's sort of yellow or. and orange. And you see that in the. forest, you're probably looking at a. slime mold. >> Yeah. Especially if it's really hot out.

and it just rained. >> Yeah, the two the worst thing in the. world for me. >> You can also see them like on your. grass, too. Apparently, if it gets. really rainy and hot, slime molds will. actually come out of the woods into your. grass and be like, "Oh, this is pretty. nice." And um they aren't going to do. any harm. It's not a problem for your. grass. It just looks kind of gross. It's. certainly not going to hurt you or your. pets. And then eventually it'll dry up. and turn to kind of a gray or tan powder. and blow away. And that means that it.

just turned into spores and it just. reproduced all over your place. >> Yeah. I think maybe we should take a. break because right now people are. probably like, "Dudes, you promised. greatness here and so far it's a little. humrum.". >> What? >> So, put those sock guarders back on cuz. when we come back, we're really going to. start knocking them off with some of. these amazing facts. [Music].

Okay, Chuck, we set him up. Let's knock. them back down. So, uh, here's one cool fact is that. slime molds basically can do the. equivalent and do the equivalent of.

throwing themselves on the grenade. >> Mhm. >> Uh, they will sacrifice themselves to. save others. And these are things. without a brain or a central nervous. system. Like, it's not like they think, hm, I'm feeling empathy today for my. fellow mold. >> Sure. >> And so, I'm going to save everybody. because I've come across some infectious. bacteria. But what they do is they they. come across it. They engulf it and then. they say, "Let me go." And they cut. themselves off from the pack, from the. swarm, and detach themselves and die of.

that infection, but save the rest of the. the group. >> And um my heart will go on playing in. the background. >> as they they get further and further. away. Exactly. >> But that's that's altruism. >> Yeah. >> Which is pretty amazing considering, like you said, they don't have a brain. or anything like that. So, how how are. they doing this? We'll get to that. later. >> So, what about uh tell everyone about. the uh dictistellium dis discitus. >> discoidites. Discoites. Okay.

>> That's one of my favorite words now. Disco. >> just because it has disco in it. >> So, that this was uh this is a kind of. um cellular um slime mold, right? So, it's made up of a bunch of different. individual organisms that come together. And when they come together, they um. practice altruism to some degree as well. because some of them will basically be. like, "Okay, I'm dead now. I'm dead. I'm. going to turn into a bundle of cellulose. fibers." And that cellulose is going to.

connect with other uh slime mold cells. that have died and turned into cellulose. and come together and form a stalk. And. then at the top of the stalk, a bunch of. different um slime mold cells, they're. called slugs when they're individual. like that, will climb up the stalk and. then they'll turn into spores. And then. in that way, they're sticking up out of. the ground and a passing animal will. come and it'll stick to it and it'll get. a ride to to greener pastures. But to do. that, some of them have to die to form.

this stalk to to let the spores grow on. top of, which is pretty amazing itself. >> It is. Uh, and you know, we mentioned. that they move. You know, they're not. they don't just sit around and wait for. someone to drop a a pepperoni near their. pizza shape in the woods so they can eat. it. >> They got to go where the food is. And. they either move by these little. appendages that like little feetike. appendages. Those are the cellular slime. molds, the individual single-cellled. organisms that can come together. >> Uh, or, and this is crazy, the the other.

kind, they move as one big mass because, you know, there's no cell wall going on. And so they just sort of expand and. contract the cytoplasm to kind of gush. their way along the ground very slowly. >> Yeah. Which is really neat to see. because when they're especially when. they're searching for food, which is. basically all they're ever doing, like. everything that they do is either to get. away from some noxious stimuli or to go. toward food. Usually to go toward food. >> It sounds like us.

>> It basically. Yeah. I don't like that. smell. >> No wonder we love them. >> But I like that smell. I'm going to go. toward that. So, um, the they they make. these amazing kind of they look almost. like sea fans. You know what I'm talking. about? They they look um very fractally. and they just kind of they fan out is. the best way to put it when they start. to go look for food. And when they do. find food, they start moving toward it. It's the the the cell walls contract and. that cytoplasm goes that way. And next.

thing you know, over a very long period. of time, >> next thing you know, 5 days later, >> the uh the the slime mold has moved. And. actually, slime molds um if you don't. they like they they're totally fine. living in petri dishes for as long as. you want them to. Um as long as you feed. them, if you stop feeding them, they'll. just get out of the petri dish and start. looking for food elsewhere. So they'll. they'll escape. >> Creepy. >> Yeah. But I mean, again, it's not like. you're just sitting there watching this. thing crawl out of its petri dish. It's. you leave overnight and you forget to.

feed the thing and you come back and. it's half of it is out onto the the. table or something like that. >> It's something like right out of. Gremlins. Uh. >> kind of. Yeah. >> And I think you said they move about a. millimeter an hour, but some of them. actually if they're really cooking can. go about an inch and a half in an hour, which. >> That's really fast. >> I mean, it doesn't sound fast, but when. you're talking about what we're talking. about, it is pretty fast. Yeah. Um, and. I saw that a couple of places. Most. people sight something like a millimeter. an hour. I can't remember which one goes.

that fast, but yeah. I mean, you can't. see it moving when you're staring at it, but over time you can for sure. >> Sure. Or, you know, if you're just. really patient and you can lock in on. something, you might be able to see. that. >> So, when they started figuring out in. the early 2000s, the Japanese. researchers were some of the first to. like really study slime molds as as. showing some sort of intelligence. They. figured this out from, you know, from. watching these things actually move. about. And when you when you film them.

in um at like high speed and then replay. it, you can see their movements are. deliberate in a lot of ways. They're. they're not just blind dumb movements. where they happen onto um food. They. clearly can sense food somehow or some. way and they spread out um and they seem. to spread out and again in a really. deliberate way. And so some some. researchers started to um test slime. molds to see what they were capable of.

One of the first ones uh one of the. first researchers. was a Japanese scientist named Toshiuki. Nakagaki. And um. >> right name. >> I think so too. And Dr. Nakagi, which is. even better. >> Yeah. Oh yeah. >> Um built a maze, like a pretty simple. maze, but an actual three-dimensional. maze in a a goodsized petri dish. put um. what what has come to be known as. probably the smartest sime mold, a. fiserium polyphylum, uh which is kind of like the rock star.

of the slime mold world these days, put. a fiserium in it and said, "Go to town. Go find your little favorite oat flake. treat," which is their their favorite. food. >> Yeah. And the key here is is there were. four different routes to two different. endpoints where this food was. It wasn't. just like a there's only one way to. solve this maze. >> And so they put the little oat flake at. these end points and uh the. microorganisms that grow on the oat. flakes is what they're after. This not. like they love oatmeal or anything like.

that. >> Right. Right. >> And so he put them there and studied. them and over the course of hours these. things basically learned to get to that. food in the quickest, fastest way every. single time. >> Yeah. like it could it could conceivably. get to it like you said four different. ways but that fast way was the way it. would just like that's impressive that. that's definitely noteworthy you can. write multiple papers on that kind of. study and so another Japanese researcher.

came along and said hold my sake. >> uh a researcher named Atsushi from. Hokkaido University did you like that. >> yeah it's good. >> and um Dr. Tiro said, "All right, what. about this? What if we take some oat. flakes and basically make a a general. map of the neighborhoods in Tokyo and. see what the slime mold does with that?". Put a little slime mold in a petri dish. with these oat flakes that kind of mimic. the neighborhoods of Tokyo and watched. it go. I think over the course of like.

uh four or five days, right? >> Yeah. And you might think, "Cool. it it. does what it does and it goes after that. food in the most direct way possible, which is what it did. >> But here's where it gets genuinely. amazing. >> is they went back and they overlaid a. map of the current Tokyo railway. commuter system, the subway system. >> Sure. >> And they laid it over this grid of this. slime. >> and it was almost a perfect match.

>> Isn't that nuts? That's I mean I had to. reread that like five times. >> to even believe that that's what. happened that this slime basically. figured out the most efficient route to. get around essentially Tokyo. >> Yes. Which I mean humans had figured out. too but it took teams of human engineers. and a very long time for them to figure. this out. Right. So the slime mold was. just like this is this is nothing. What. else you got? you got any more cities.

that are more densely populated with. more neighborhoods because I'll just. make your subway maps all day long. basically. >> And they're like, no, Tokyo is probably. one of the most dense, >> right? >> Like, okay. >> I saw another um another similar kind of. uh bit of research, Chuck, where they. actually used oat flakes to signify. ancient Roman cities in the Balkans. Oh, >> wow. >> This is this is crazy. This is like an. archaeological study. Um, and they put. some they stick some fizerium on it and.

fiserum on it and it mimicked ancient. Roman roads that had been lost, were. very obscure, had largely been forgotten. and ones that were well known in the. Balkans. It it mimicked these these. Roman roads like things that people had. been like, "Okay, this is the best route. from this city to this city." the the. slime mold did basically the same thing. and and apparently revealed some lost. stuff. >> Yeah. I mean, I guess it could also it's. interesting like if it doesn't match up.

if they do an experiment like this, does. that mean like the humans get it wrong? Like can they use this as a test and be. like, "Sorry, the slime mold is spoken.". >> I guess so. I kind of like the octopus. picking the World Cup. you know, they. always take the World Cup away if the. other team that the octopus didn't win. ends up winning, you know. >> Well, I wonder if you I mean, and we'll. get to real applications of this, but I. wonder if they could do something like. that where they let's say they look at. the Tokyo system and a couple of places.

it didn't match and they're like, we. totally should have gone this way. >> Yes. I feel like that that is the. direction that people are kind of going. in that they they could conceivably use. this for planning new stuff, you know. >> Wow. So, every city planner will have a. slime mold researcher at their behest. >> Yeah. I mean, like that's. >> crazy. >> Why not? You know, >> all you have to do is have some oat. flakes in a petri dish and you're good.

So, I think we should take another. break. What do you think? >> I quite frankly want to eat some oat. flakes right about now. >> I'm kind of in the mood for that, too. We'll be right back. [Music]. Derryface. [Music].

>> Okay. Did you just eat some snowflakes? >> I did not. >> All right. We'll get you some. >> Cuz here's the secret, everybody. When. we take a break, we don't really go take. a break. >> No, you could have had some crusty old. oat flakes on your desk and just eaten. them real quick. I I don't know. I can't. see. >> So, all right. We've said that these. things don't have brains. They don't. have And I don't think we mentioned they. It's not like they have like a It's not.

like they're jellyfish and they have. some sort of weird neural net, >> right? >> They got nothing like that at all. >> Nothing. like they have no way of of. generating consciousness in any form. that we recognize. And yet slime is. teaching us to open and open our. horizons um. >> and hearts. >> to sure to new ideas of what constitutes. consciousness and intelligence. You know. what I'm saying? Like it makes sense as. a swarm as a bunch of cellular a.

cellular slime mold makes sense. We're. already familiar with the hive mind and. you know the emergent property of a. bunch of different things you know. operating together. The real puzzler. though is the the single cell plasmodial. slime mold that's one big giant cell and. the fact that it behaves in ways that. seem conscious to some degree. >> Yeah. So, if you want to kind of go back. in time to where a lot of this re uh. research started, uh it it wasn't. actually in Japan, but it was in the.

1960s. A physicist named Evelyn Fox. >> Keller. >> was curious if she could use math to. model biological systems because they. had had success using math to explain. and expand our understanding of physics. So, she was like, "Let me see if we can. do this with biology." And someone said, 'Well, you got to meet Lee Seagull. Lee. Seagull is uh got a little surprise for. you. And Lee Seagull got together and. said, "Oh, uh Dr. Keller, you need to.

meet our friend Slime Mold." And Dr. Kell was like, "Uh, this is the 1960s. I. don't know what slime mold is yet." and. Keller and uh sorry, Seagull said, "Oh, well, just take a seat and let me tell. you about this uh what which is dictio. dictioellium.". Dictto, right? >> Mhm. >> Dictostelium. discoidium. >> I think that's discoides. >> Discoium. >> Yeah.

>> Okay. >> But it's the one we were talking about. earlier that that creates the stems. They sacrifice themselves to create. stems for the spores, >> right? And I think this was just. significant because it was kind of like. the first time anyone had observed and. you know fell off of their lab stool and. could explain it to others these. pseudopplasmodiums. But what they were. missing was they were like all right we. see this happening and it's amazing. >> and how are they doing this though? And. the the very first thing they thought of. is like maybe it's like an ant colony or.

something and maybe there's like a. leader or a pacemaker cell or maybe a. few of them that get together and they. just sort of send out chemical signals. to everyone else and say go this way and. the rest are just sort of the worker. ants that follow along. >> Yeah. And they knew in particular that. there was a a chemical called cyclical. AM which is related to ATP, the. adenosine triphosphate. Um, and that that was how they were. signaling. But they thought that that.

like you're saying that there are just a. few signaling everybody else was. responding. And what they figured out is. that that they had that totally wrong. that there weren't leaders, there. weren't pacemakers who were in charge of. like, you know, signaling and in effect. making decisions for the group. that it. was actually like a group effort in that. the the whatever um whatever cell or. slug that they're called in this. cellular slime mold swarm was closest to. food. It would signal uh a with ammp. that hey, there's some food over here.

Let's all go over this way. And that. signal would just kind of be passed. along through the swarm through the. cellular slime mold and the slime mold. would move toward the food and start. eating. >> Yeah. And this was, you know, I mean, it. you can see why they went in that. initial direction because it made sense. And a lot of nature is organized with a. top- down principle in mind. Humans. often organize with a top- down. principle, big business, government. It's just a it's a system that we're. used to seeing in in nature and in.

people. And so, it made sense that they. went that way. And they never they never. really thought about the fact that it. could be like, no, they're uh it's a. total bottomup system. and whatever is. closest can s out these signals. >> Yeah. So instead of like a hierarchy, it's more like um like it's like how a. flock of birds operates. A flock of. seagulls haircut operates where. >> they run so far away. >> Yeah. But it's the hair that's closest. to whatever it it's running from is the.

first to run and everybody else follows. This is kind of like how a flock of. birds will turn depending on, you know, which way they need to turn based on. that bird making that decision and the. rest of the f flock basically following. it. >> It's a bottom up bottom up decisionm. kind of thing. And so we started to. learn a lot and we know a lot about. bottomup decision-m now as opposed to. when these guys were working back in the. 60s I think. Um but in the 21st century. that whole idea of bottomup.

decision-making or decentralized um. decision-m. um has become a real component in in uh. artificial intelligence design because. if you've listened to the end of the. world with Josh Clark, you know that one. of the hardest things in the world to do. is program something to understand. everything because you have to input all. the stuff it needs to know. Whereas if. you can just kind of set up some sort of. simple algorithm to let the the machine. think for itself, you you finally got.

something. >> Yeah. And I would imagine I didn't see. this anywhere, but it seems like this. might could have some applications in. nanotechnology. as well. Like the idea that we could. program, you know, billions of tiny. little nanobot bugs to clean the windows. of your house every day. >> Nice. >> Uh like a lot of things collectively. doing one bigger thing. >> Yeah. Uh, am I off base there or could. that potentially be a thing? >> Not at all. I think it totally could be. a thing. It's it's anytime you have a.

huge amount of things that you're trying. to all get to do roughly the same thing, but they need to not, you know, uh, re. redouble their efforts or um, uh, replicate their efforts. So, you don't. want one cleaning one part of the window. and the other one coming over and. cleaning the the same part of the window. that's already clean. Um, all you have. to do is figure out how to teach them if. if this happens, do this. And if you can. figure out how to strip it down to a. basic enough algorithm that could.

conceivably. be used for just about any situation, um, you've got the key to the universe. in your hand. Like there's actually I. read we'll have to do an um an episode. on it one day, but I read an article. about a guy who was a I think he was a. physicist back in the 80s who was like I. think the universe is basically an. operating system. >> that is that is that is goes down to to. two there's two bits you could say it's. black and white one or zero it doesn't.

matter but there are two kinds of bits. and depending on the combinations that. these things form everything else in the. universe arises from that, including. consciousness, planets, slime mold, everything comes out of these two types. of bits that basically make up the. fabric of space and time interacting. with one another in increasingly. sophisticated patterns. >> Wow. >> And that is exactly what you're talking. about. So if if we can figure out what. that that computation is, what those.

algorithms are that give rise to larger. and larger stuff, you can you can do. anything. It's it's weird. You can do. increasingly sophisticated stuff the. more basic your algorithm is. It's. almost a paradox. >> Yeah. This is like Dr. Octagon stuff. >> Dr. Octagon. >> I don't know. >> Is that right? From Spider-Man. >> I don't. Yeah. He was uh Alfina, you. mean? >> Yeah. >> Sure. >> All right. >> I like Alfa Molina. I think he makes.

some really weird choices for parts. >> Oh, he's great. I'm sure somebody's. like, "Hey, we'll give you $10 million. to play Dr. Octagon." I'd be like, "Sure, you got it. Where do I sign up?". >> Yeah. I need to get him a movie crush. because he actually is friends of uh the. network. He's a friend of the network. I. think he's been on the Daily Zeitgeist a. few times. >> Oh, yeah. >> And like they booked him on some other. comedy shows. I'm like, "Guys, throw a. little Molina my way.". >> For real. Get that Molina spread all. over Movie Crush. >> You've been on Daily Zeitgeist twice. >> I've never have.

>> I've been on Movie Crush once, too. I. had uh Miles on the movie Crush the. other day and I was giving him a hard. time because they haven't asked me on. and they keep on twice. >> That's hilarious. Keep it up, Chuck. Keep it up. >> He was like, "Uh, no, man." I was like, "Miles, it's cool.". >> Did he really? You flustered him. >> I feel like he was on skates for a. second there, but that's hilarious. >> I let him off the hook. I'm having Jack. on next week, so I'm really like going. full court press here. >> Yeah. Miles is like, "Man, be be on. guard. Chuck does not pull punches.".

It's funny because Miles, you know, as. you know, is such a smart smart guy. >> and uh just like having a conversation. with him is always amazing. And then he. comes on and he picks Maul Rats was his. favorite movie. >> Was it really? That's his favorite movie. of all time, huh? >> I mean, that's what he picked. And he. was like, "Hey man, I never said I had. good tastes." So, it was pretty fun. >> Do you have any hints of what Jax is. going to be? >> Well, I know it it's uh Pulp Fiction. because he Okay. He had me save it like. two years ago and I just, you know, we.

kept slipping through the cracks. So, he's going to come on next week for Pulp. Fiction. >> Very nice. >> Uh, all right. So, let's get back to I. mean, we talked about how the uh the DD, as we're going to call it, moves around. without. >> Yeah. without a the pacemaker cells. But. that original true slime mole, the big. single-sellled one that's just made up. of all the goopy cytoplasm, we didn't. really talk about what they do. And uh. because if you don't have cell walls, you're like, well, how's this stuff. moving around? >> It's uh actually made up of what's.

called oscillating units. >> And so these units oscillate at. different frequencies depending what's. going on, like where they are. >> and then what the their little neighbor. oscillating units are doing. And so when. they go close to food, they start. oscillating and shaking like, "Hey, hey, hey, I'm near some food." And then that. just sort of gets that flow. everyone. else starts oscillating in a similar. manner and that gets that flow of. cytoplasm going in that food direction. >> Yeah. And so the slime mold effectively.

moves to the food because of that that. oscillating unit that looks again like a. a fan spreading out going to find food. and then finding it. The slime mold. moves toward it. >> or like you said away from something. that they don't like. >> Yeah. Yes. Um which is pretty neat. So. So those are the two things. it's moving. toward food or moving away from. something. And um one of the the things. that they found is that slime mold can. actually um learn and not only learn to.

like stay away from something, it can. actually teach other slime mold um to. stay away from it, even slime mold. that's never been introduced to it. Or. alternately, it can teach this is the. really the sock guarder uh fact. It can. teach other slime mold that something. that seems harmful is actually harmless. >> Yeah, this is a pretty cool experiment. >> Yeah. >> So, these researchers put slime molds uh. they built a little tiny bridge. It was. very cute. And they coated this bridge.

in a noxious substance. Uh it wasn't. harmful to them. It was harmless. It was. like salt or something, let's say. And. then they put the little those little. oat flakes on the other side as their. ultimate temptation. And so these first slime molds start. creeping up to it and sort of dipping. their little toe in the water and. saying, "Uh, this stuff is pretty. noxious." But then they learned, >> so gross, >> right? Like, oh, okay. So, it's not. actually harmful. I can go across this.

stuff. And what they found was that it. learned to cross this little bridge just. as fast as slime molds that were placed. on bridges that didn't have any coating. going on. >> Right? So, it said, "Okay, this stuff's. fine. It tastes gross. It's way too. salty, but it's not going to hurt me, so. I'm going to get to food just as fast. Right. That's pretty amazing in and of. itself. >> But here's where it gets crazy. >> Yes. Right. They um we need like a Ben. or Matt or Null to come in and say that. >> Yeah, totally. >> Um so they they take the slime mold and.

break it apart and fuse it together with. other slime molds that have never been. exposed to this noxious stuff before. They're called naive. And the other ones. are called habituated. And those naive. ones when they encounter this noxious. stuff like a salt bridge for the first. time, they don't approach it with. trepidation, they go right across it as. fast as the habituated ones that it's. fused to. Yeah, >> this is really weird that because this. is the first time the stuff's. encountering it and they think that.

somehow the habituated slime molds are. passing on the information like, "No, no, we know it's gross, but it's. actually fine to the naive slime molds.". And they figured out, Chuck, that it. doesn't matter if you take three. habituated slime molds and fuse them. with one naive slime mold or take three. naive slime molds in one just one. habituated slime mold. It's going to. approach us and move across it just as. fast as as either in either situation.

>> Yeah. And then they also sort of figured. out how long this took. So, the naive. slime molds, they separated after an. hour of fusion with those uh habituated, I'm going to call them in the no molds. >> Okay? >> And it forgot. It forgot that the. coating was uh harmless and it sort of. had to approach it with a little more. trepidation. >> But if they had been fused for 3 hours. or more and then separated, it it. remembered. I mean, it technically can't. remember, but they do have this weird.

sort of memory uh that works. And and I. think they even figured out. >> some of this snail trail stuff that they. leave behind acts as sort of like a. spatial memory cuz they come across this. snail trail and say, "Oh, someone's. already been here before me.". >> Right. So, there's no reason to go. research this area because there clearly. wasn't food there. Yeah. And again, here's your 10-minute. reminder that slime mold don't have. brains or neurons. So, all of this is.

just just astounding stuff that we're. still trying to get to the bottom of. Like that habituation thing, they're. like, "We don't know. We have no idea, but we're going to go find out and maybe. in 10 years we'll be able to explain it, >> right?" So, eventually, um, you know, the the people that are, uh, people that. are hip to the slime m mold thing are. like trying to spread They're trying to. spread the word and be like, "This stuff. is really amazing. They're doing TED. talks on it." It was a really good TED. talk on it, in fact. >> Mhm. >> And some coders said, "Hey, wait a.

minute. You know, they're doing all this. amazing stuff like the overlay of the. Tokyo subway and it's lining up. perfectly. What if we actually generated. code of the slime mold and kind of. reverse engineered it and and we could. see what that looked like and how we. could use it?". So, yeah, this one artist named Sage. Jensen basically figured out um or took. I I don't know exactly who figured out.

exactly what the the slime molds um. algorithms were, but somebody wrote them. down and Sage Jensen came along and. turned them into C++ code and basically. ran these things. is like algorithms and. found that these fractals started. forming that look essentially just like. slime mold moving across a petri dish in. search of food, which is pretty cool in. and of itself. It was an art art project. basically. But some someone on a team of.

astrophysicists heard about Sage. Jensen's work and they used it when they. were stumped trying to figure out how to. map the um the invisible matter that. makes up basically the structure of our. universe that that if we can just crack. that nut, we'll understand the universe. exponentially better than we do now. But. we cannot figure out how to do it. And. so just like with the ancient roads the. between the Roman cities or the Tokyo.

subway map, someone figured out to use. slime mold to basically try to try to. create the structure of the universe. This invisible these invisible. filaments. >> Yeah. These filaments that came out of. the Big Bang. >> Mhm. >> So I guess they went back to Sage Jensen. and said, "Uh, first of all, Sage, you. use C++ code. Isn't that really just B. minus code if we're being honest?". and he said, "That's not how it works. Get out of my office.". >> That's a great coding joke. >> Uh, thank you. It's my only coding joke.

and I just made it up. >> It's the only coding joke, I think. >> No, I think uh it's not a bug. It's a. feature. Isn't that one of the. >> Oh, that's true. True that. >> old timey. Um, so yeah, they they went. to Sage and they said, "You're an. artist, but this is pretty amazing. I. think we can apply it here." And they. modified it. And uh what they did was, and of course there's always oats. involved, um they put a model in place. with virtual slime mold cells, and they. put it on a map with 37,000 real.

galaxies. And they used uh I guess virtual piles. of food to represent uh the galaxies. And the bigger the galaxy, the bigger. the pile of food. >> And so they did this modeling through. the coding and had the virtual slime. mold seek out the most efficient way to. reach this. And I guess in theory. they're hoping that they get a a sort of. map of the universe out of it. >> Yeah. So So when the slime mold was. finished, they all stood back around.

That's amazing. How accurate is it? And. they all just realize that they had no. idea how to verify. >> But no, surely like I think what they're. doing is they're taking this as an. initial, you know, guide and then. they'll go back and try to figure out. how to verify it. And maybe the slime. mold did figure out the most efficient. way to link together these galaxies. But. that would be. I can't even put a word on that of what. that would how impressive that would be. if the slime mold recreated how the.

universe is invisibly linked together. the structure of it. You know. >> what if slime mold is God? What if we're. asleep right now and this is all just. one dream? Chuck, >> uh, the other cool thing they figured. out with the slime mold moving around. is, uh, when they were researching them, they found that they, those mazes that. they were running them through, they. went even faster through the maze when. they had some sort of noise, like a. bright light or something, like we said, they like to go away from things they. don't like. >> Mhm. >> And that negative input of that light.

>> basically made them say, "All right, let's let's pick up the pace and make. these decisions quicker and get to that. food. >> Let's stop fussing around. I don't like. this light staring at me. >> I think we kind of blew some minds. today. >> I think so. My mind's definitely been. blown. >> Did you want to cover the Amazon thing? >> Nope. >> Okay, good. Uh, that's it for slime. Unless you got. anything else right now, do you? >> I got nothing else. >> We'll have to revisit this in 10 years. And thanks to Dave Ruse for helping us. with this one. Um, and since I said Dave.

Ruse, I think Chuck, it means it's time. for listener mail. Hey guys, I'm going to call this uh. Night Trap. response. >> I just laugh every time I hear those. words together now. >> I know. Night Trap. Uh this is from. Aaron. Hey guys, just finished the Night. Trap video game show. Thanks for. bringing it to everyone. I own the 25th. anniversary edition. Like you said, it's. not a good game, but has its moments. One other game worth noting is called. Double Switch. It's of the same style.

and video camera control quality, and it. starred Corey Hay. uh perhaps arguably a. little better game, but still had the. same thing going on. Really? I'm sure. your research finds lots of things that. don't quite make it into the final show. Uh Aaron, we did not know about Double. Switch. So, nice work there. >> Yeah. >> Uh and Aaron says, "I've listened to so. many shows, I feel that Chuck and I are. some sort of long- lost brother, separated at birth. Uh generally agree. with just about everything he says, and. I'm always fully entertained. It would. be nice to meet you guys if you ever get. another tour started and make it back to.

Michigan. keep up the good work of. finish your book and I have the. pre-order poster in my office and I've. converted friends and family. So that is. from uh Aaron in Michigan and we're. definitely going to start touring again. I I would say probably next year. although we haven't really talked much. about it. >> No, but we need to. It's definitely. starting to get to be time to to get. talking, I guess. Although I I got to. admit I have not missed the traveling. I've missed being on stage but not the. traveling part. Well, you know, that's.

what they say. That's what rockstars. say. >> It's not the heat, it's the humidity. >> No, they say that, you know, you get. paid to travel. You don't get paid to. play shows. >> I've never heard that before, but it. really makes sense. >> Yeah. >> If you can figure out how to get paid. for both, then you're really really. doing something right. >> Good stuff. Yeah. And if we get back to. Michigan, we've already done Detroit. Uh. we've had a lot of calls over the year. for Ann Arbor, so maybe that's where we. go. >> Yes. Um, well, who was that again?

>> Aaron. >> Aaron, that's what I was going to guess. Thanks a lot, Aaron. That was a great. email. Thanks for the Corey Hay. reference and all that stuff. And if you. want to get in touch with us like Aaron. did, you can send us an email to. stuffodcast@ iheartradio.com. [Music]. Stuff You Should Know is a production of. iHeart Radio. For more podcasts, iMheart. Radio, visit the iHeart Radio app, Apple. Podcasts, or wherever you listen to your. favorite shows.

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