We Can Rebuild Them!

can't we be parts? Salamander Joining me today is a TV writer whose articles and columns have been featured in The New Yorker Guardian and l A Times, who also writes on some show called Some More News. Dave Schilling, Hello, Wow, what a delightful intro. I always try to complement the hosts on their intro because it sets the tone of congeniality and friendships that I like to in gender one I go on a podcast, thank you all artificial, I'll just sort of a baby welcome down Hollywood. All. Just

just peel my face off. Damn it, I knew it. Yeah, well, no, thank you very much. It's it's a treat to have you on here, because we are talking about animals who can regenerate themselves, which is inspired by a news story I saw about a cea slug, which I love it when there's nature news and it's just like, hey, look at this cea slug. It's headless, and it's like, yes, you've got me, You've got me right where you want me.

I'm intrigued immediately. Yeah, It's like I normally kind of recoil at clickbait, but when it's when it's like, yeah, check out this headless sea slug, I'm like, yeah, no, I'll do it. It's moving around. That's good. I'm clicking on that for sure. Well I am the opposite, and in that I see it and I say, no, thank you. Uh, it's enough that you've described a ce cea slug without a head. I don't need to see it. I know what it looks like, and it's not for me. I

can paint a mental picture of it. Right. What is your relationship with with squiggly animals? Not not a big fan. This is a great question. And when I told my girlfriend I was coming on this show, she said, you hate animals, and I'm I guess you're right. I do hate animals. I don't dislike them that strongly. But I was never an animal person because I didn't have pets growing up, which is strange because I grew up in one of the more rural and and uh agrarian parts

of California. This little town calledmer said, everybody understood farming and did four h and you know that was part of the culture. I was just I wanted nothing to do with it. They smell bad, they lick you, uh, you know, they pissed wherever they want. I don't have that. I don't have those liberties that I can take where

I can. Just jealous, So you're just jealous a little bit. Yeah, imagine if you could just kind of wander the earth, grazing off of the land, defecating wherever you please, not having to work, not having to fill out unemployment insurance forms, not having to put gas in your gas tank. You just,

you know, amble down the road eating grass. I mean, you occasionally get slaughtered by some kind of predator, but I think it's worth it to not have to fill out forms, to never deal with bureaucracy again, and just occasionally get murdered by a lion. Yeah, let me think about this. What I prefer the abattoir or the d m V. I'm taking the roasted the TMB. I bet they never saw that coming. No, this is the first time anybody's ever maligned the DMV. Shocking, George Carlin level groundbreaking,

you were a serbic satire. It'll be like one of those fun things like with a podcast where you have the Gift on and you're just like constantly grossing them out and they're not having a good time, but we we all we all share a good laugh. Yeah. I'd say one of my favorite podcasts is when they don't have a good time, when when the guests is visibly sick and iwice is like trying to navigate their psychosis. That's my favorite. Right when the gift is nauseous the

whole time. That's that's the sort of or the the environment I'm trying to cultivate on this podcast. Isn't that what Joe Rogan does? Oh? You know, I don't know if that's intentional, but another one man, Joe Rogan, He's like the d m V of podcasts. Am I right? I hope that I hope that I learn and something today I might not revel in it. The way that you will. But I want to learn something. And I think as long as we're both open to learning, both

going to be happy people. Yes, I think that, And this is a good message for the listeners to, like, we're gonna we're gonna learn some stuff about animals. Listen, you don't have to like the idea of self decapitation. I'm not trying to get you to like be calm about self decapitation, but to understand it more, you know, to get to know. I think understanding something makes us less afraid. So if you if I'm saying, you know, hey, look at this animal pulls off its own head and

keeps on living. Your first reaction might be terror, But let's let's have that reaction turn into understanding and knowledge, empathy, empathize with this creature. Right right when a little girl like has her head do a three hundred sixty degree turn and then says like, I want to play with me, Like I think you need to learn, Like, do play with her? Find out like, you know, just explore the world around you. Yeah, she's literally just asking to connect's.

She doesn't necessarily want to kill you, Yeah, like you just want to that kid in the shining with such a snob. These little girls ask them to come play with them. It's like, you know, they're like and play with us forever. That's awesome. Todd Browning's freaks one of us. They wanted to have a little gang, a little friends, so fun, fun times. So we're gonna have fun times with self decapitating sea slugs is the point. So self

decapitating sea Slug. I feel like every topic on this show sounds like a good metal band name, and it just is a rule like it always it always happens. So yeah, self decapitating c slug good metal band name. We've actually talked about plenaryans on the show, which is a type of flatworm that can regenerate itself if you chop it up into little pieces. So if you chop off its head or cut it in half into little pieces, like Gordon Ramsey could just go to town on one

of those things and it would keep regrowing itself. Just pretty great. Um. But the discovery of the sea slug is unique in that it it actually it's not just that it regenerates it self decapitates. It decapitates itself, which kind of sounds like a weird sea slug fetish um, but apparently it's not um. So first I want to thank New York Times science writer Annie Roth for her

amazing article on this subject. So researchers discovered this self decapitation habit in lab raised Elisia marginata, which is a green and orange sea slug that looks kind of like a wavy, succulent plant. I actually originally misread its scientific name as margarita because it kind of looks like a margarita to me. It's like green and it's like a like sort of pink or orange e pink on the rims, so it's like it's like a refreshing Margarita's it's it's

covered in salt. I think that would be bad for although it is a cease look, so it is naturally covered. Insult if you have if you have three of them, your pants just fall off. You know, it's just like a margarita. Anyway, Um, this guy, why does he do this? Why does he take his head off? That is an excellent question. Here's a question, like if you had the power to take off your own head just for you know, like would like would you? I mean, it wouldn't hurt you,

like you wouldn't die, but you could do that. Would that be a fun superpower to have? Or would you just pass on that? I don't know what I would do with that super volleyball. Uh yeah, walk around the grove and freak people out it. Maybe you hide your head in in a closet and then you can observe other people doing things like you know, you can be a voideur of a sort like the Invisible Man, but

it's your head. Um you could you could, uh you know, put your head in uh in like a like the an office of a movie studio, and you can get a bunch of spoilers the latest Marvel film. I don't think I would want to do that though, because then where could I go when my head was off, um, nowhere, because I don't have a head. So self defeating and

self decapitating. Self defeating and self decapitating. Yeah, I mean though for me, if like I could just set my head up in front of the microphone and continue to podcast where my like, let my body roam around the apartment bonk into things, maybe like put some like food down my neck hole, you know what I mean. Like it seems you know, I can take a nice nap right now, Yeah, take a nap with my body and fold some laundry while I'm doing podcasts. Oh, I should

fold laundry while I'm to podcast just with my normal body. Yeah. But what if, like you need to hit the stop button on the record or something, you call your body over and your body is like nah, I'm taking it out. But yeah, so your question is a very good Why would a ce slug want to self decapitate doesn't want to spook its friends? Well they looked into this, and there's actually something called self amputation or autonomy in other animals.

So lizards will detach their tails and it's often used as a self defense mechanism. So if the lizard gives the predator the tail and escapes, she lost her tail, but she keeps her life and it's a good trade. But this habit of voluntarily amputating your whole body is new. And what's even more interesting is that like these specimens they saw doing this were in a lab, they weren't being pursued by a predator. So what was going on?

So the restart True started studying the sea slugs self decapitations, because that's what do you do as a research. If you find an animal in your lab is cutting off its own head, you're like, Okay, you know, I guess we got to look into this now. So their research seems to indicate that the self decapitations are a purposeful way for the sea slugs to ditch their bodies when they become infected with parasites, which, oh, okay, this makes sense. Yeah,

I get it. I actually, if I became infected with parasites, I think I would want to just get rid of my old body and grow a whole new one, you know what I mean. Like I've done I find like like you have tape worms. It's like, all right, we gotta just like that's it. I would do that if I had like really bad gas, right, just get rid of the whole body, get a new another body. Uh. I did think of one excellent use of self decapitation.

Let's say in the near future, when it's possible, you're at a party and you're hanging out and you know, having to drink or eating some snacks or like hanging by the ox cable and picking the songs because you're antisocial. Somebody comes by and says, oh, I'd like to talk to this person because they're interesting or cute or whatever. Well, if you want to get rid of a pesky party guest who is hassling you or is inane or boring or offensive, instead of you know, just being rude, you

pop that old head off and freak them out. They're like, I want to talk to somebody without a head, and then they scamper away and then you pop the head back on. All right, that person hit the bricks and you're good to go. Yeah. No, I do like that. I like the escape sort of in your scenario. It's similar to autonomy and nature because they do it to escape predation, and in this scenario, you do it to

escape an awkward situation. I think I would probably set up like one of those little miniature basketball hoops in my apartment or wherever, like the trash can hoops where you throw the trash in and it goes into a little bucket, but with my head. So if someone's like, how's it going, do you have any new projects going

in on in your life? Like what's new? And like I don't want to answer because literally nothing is going on in my life and I don't know how to answer, like what's new with you, and I'm embarrassed just check my head into the hoop and go like who this is? Yeah, I think we've we've setched out why this should be the next stage of human evolution and being able to

take off your own head. Yes, And the way to do it if we're going to copy the sea slugs mechanism is they actually have it's a clean cut, which is interesting because they don't actually have little tiny sea slug guillotines that they use. It's they actually seem to dissolve the cells around this sort of amputation line so that their head just can kind of like you know, pop off of their body and they will regenerate from that like area from the stump, uh, an entirely new body.

Within actually a few weeks, their body is starting to regrow, maybe not to its original size, but it is. They actually get a new body the old body actually, so it doesn't regrow a new head, but the old body does remain alive for like a few months, and yeah, it reacts to getting poked. It's eventually gonna die because there's no head and it apparently can't regrow ahead. So it's not like the sea slug becomes too sea slugs, but the body just kind of shambles around for a

few months before finally decomposing, which you know is neat. Yeah, I suppose. So it also looks like a potato chip here, like you know, one of those like those tara chips that are multiple colors, like looks like a tear chip er oh yeah, yeah, where it's like made out of some kind of yam instead of a potato and you convinced yourself it's as good as a potato chip, but it's not. It never is. It's disgusting. Yeah, like this, like I imagine this sea slug is if I would

eat or her. Okay, I don't know though. That's seen from the from the Lion King where they're eating all those boogs. You know, this looks like one of the good ones, one of the good, the good ones that they Yeah, you know what this is. I think this, this sea slug is an ally for sure, one of the good ones. So another cool thing about these self decapitating sea slugs is they also practice kleptoplasty, which is when they steal chloroplasts from the algae they eat and

then hijack them for their own solar power production. So the sea slugs can then derive energy from the sun like a plant because they've just stolen the plant's method of energy conversion. Uh. And so yeah, they are solar powered body regrowing auto decapitators, which I think is cool. Yeah, that's also a great name for a metal band. It is. Yes, it's like nothing that I say on this show couldn't be turned into a metal band, you know what I mean?

I agree. I think you should get T shirts made up look like metal band t shirts, but they say self decapitating slugs instead of Danzig. I do like this. This is a good merch opportunity. Yeah, just have like the metal font and then a sea slug like on some drums. But it's just its head. So how's it playing the drums with the with the arms or bouncing from drum to drums. Oh, it's like the two little

um It's little antenna are the things? Yeah? Yeah, yeah, exactly, stock exactly see I stocks is that they're called um or they're they're they're either called tentacles or right off wars. Actually, you're right, these are not ice stalks. In land snails, those are ice stalks, but in the sea slug they're they're called rhino four's they have they don't have the eyes on them, they have sensory organs. Though, who's the expert now? Could it be me? Yes? So now it's

your podcast. This is the rules, all right, Katie. The next thing we're gonna talk about is the salamander that regrows limbs. This is true. But first we've got to take a commercial break. Oh wait, no, no, it's your podcast now, so you okay, all right, up next we're gonna talk about a salamander that recrows it's limbs. But first let's pause for a commercial break. And now you do the whole outro by memory, the whole outro by memory.

While the sea slugs self decapitation is the most impressive form of self amputation, the award for drama has to go to crabs and other crustaceans, who, when faced with a dilemma, will with a flourish rip off their own arms to escape danger, or simply to ditch an injured claw. From a crab who rips off its own arm and throws it at a seagull to escape predation, to a crayfish who amputates its own injured claw after escaping a

pot of boiling water. There are many dramatic escapes caught on video of crustaceans flipping their attacker the ultimate bird, by shucking off their entire arm. Eventually they'll be able to grow their arm back. In fact, some commercial fisher's de claw crabs as an allegedly more sustainable form of fishing. They'll catch the crab, rip the crab claw off, and chuck the live crab back into the ocean, albeit missing

one or more of their arms. The thought is that by harvesting only the crab claw and tossing the rest of the crab back, the crab at least has a chance to regrow its limb continue to live and reproduce. And while it's an interesting idea, maybe it's tad diabolical, it's not yet proven that this really is sustainable, as limbit generation and crabs does take time and energy, so

there's no guarantee they'll actually survive. The trauma also seems kind of mean to the crabs, but at the same time, I guess it's better than the whole crab being dead. I'm not a crab, or at least not yet, so I can't speak for the crabs. When we return, we're going to talk about the surprising acts of regeneration happening inside our own bodies. Humans can't regrow limbs. If I get in a fight, I can't simply throw my arm at someone run away while calling out my classic catchphrase,

I gotta hand it to you. But as embryos, we have surprising superpowers. If we lose a limb bud as an embryo, the tiny nub from which a whole limb will grow, we can regenerate a new limb bud. This is due to the preponderance of stem cells we have as developing embryos, the undifferentiated cells that can become any cell that are growing bodies neat. But even as adults, we have some regenerative capabilities where you might least expect it are spooky skeletons. Are ready to talk about skeletons.

I know it's not Halloween, but you know, yes, I wasn't here if I was back in. Yet we're back in. We're back in, and we're talking about skeletons. I would love to talk about a skeletons. Every time you think that you get out of out of talking about skeletons, I pull you back in. Yeah, just like in The Godfather. Yeah. So I think our skeletons are really interesting because our kind of perception of skeletons is like, it's like the

spooky stuff that gets left behind after we die. You can play it like a xylophone, but it's basically dead. It's it's not it's not living tissue. It's like, because it's not living tissue, it's the only thing that's left behind after after we were dead and get eaten by vultures and worms and stuff. But our bones are actually very much alive, which is kind of a weird thing to think about. I guess, like, you know, like we

have this whole living skeleton inside of us. I think of of bones as, like you said, kind of a waste product of a dead person or or the things that are inside of me to keep me from turning into a pile of you. Yeah. Yeah, I don't. I don't really. I don't think about the fact that there's there's all kinds of information going on in there. It feels like sort of the rind of the human You know, when you eat a chicken, you got these leftover chicken

bones and just you know, throw them out. You can know on that bad boy for for days and still get stuff out of it. Yeah. No, I actually crack open chicken bones and suck out the marrow, which uh some people find unpleasant to look at, So I don't start people. Do you do that? You crack them open and suck suck the marrow out. It's you can eat it.

I mean you have to be careful. I don't necessarily recommend everyone do this because like, you don't want to get like a little if the bone is like cooked, Like you don't want to get a chunk of uh you know, pokey chicken bone down your throat, So be very careful. But you can't actually eat like the marrow inside bones. In fact, if you've ever had at a

restaurant bone marrow, uh, it's it's actually really good. You can like have cow bone marrow where it's like spread on toast or something and it's, uh, it's actually really full of of protein and fat. So do you you live with another human being? Right? And you do this in front of them sometimes sometimes and what is this person? Your person think about this particular pthology, I guess is the probably he's just glad it's not him. You know,

that's a good answer. Oh boy, I mean I licked my plate and my ex wife thought I was a absolute pig. But this is another level of making your meal um a little more. I guess what's the word waste free? Yes, yeah, just tell your wife. At least I don't eat the bone. I don't suck the marrow out of a chicken bone for fun anyway. Again, be very careful doing that. I don't want people to, like, you know, like everyone's going to try this now because they're like, oh, Katie does it must be cool, but

don't choke on a chicken bone. Yeah, Katie's gonna tell you be careful. I'm gonna tell you don't do it. About that, how about don't how about whatever she said, do the opposite and then we'll be fine. Yeah, sure, all right now, I'm cool with that. So you might not think of your bones as being living tissue, but

it very much is. So the part of the bones that we think of, like you know, the spooky skeleton plate like a xylophone, That is the ossified part of the bone made of calcium, and that is indeed left behind after the rest of our bodies decay, and that is basically the only non living part of the bone um. One of the functions of the skeleton is for skeletal support, as you mentioned, Dave, like, so we don't turn into

a puddle of jello. I remember learning that in preschool where they showed us like what would happen to a human body if you've removed all the bones? And it turned into like a human pudding And it was vaguely traumatic, and maybe it explains why I am the way I am now on they showed you a human goop? Where did you? Where did you grow up? San Diego? Folks, if you're in California, if you work from californ you know with San Diego is where you dreams go to die.

This is all checking out. The laid back surfer culture is just a front from the diabolical things going on beneath. So yeah, so that is one of the functions. It supports muscle tissue UM, but it also has other functions. So inside the bone is the marrow, the spongy living tissue that's very important for our bodies. So stem cells in the bone marrow actually foster cell production. So there's

red and yellow bone marrow. Red marrow produces blood cells, platelets, and white blood cells, whereas yellow marrow stores fat and produces cartilage, fat and cells that will construct the bones themselves. And here's a question. So if bones are just you know, these kind of this dead framework that supports our bodies, like, how do we why don't we just have like a

baby skeleton in us? Right? Like they we somehow go from being a baby with like a baby skeleton to being a full grown adult with like an adult skeleton. So the skeleton is growing with us somehow. And it's actually really interesting the way that this works. So bones are very dynamic and they go through an incredible process of planned destruction and renewal that continues throughout adulthood. And

it's called bone remodeling. Again another metal band cover. Also, I feel like, you know, that would be in Nightmare Before Christmas or something. It's like, that's like the construction, the spooky ghost construction thing is bone remodeling. I was gonna say bone remodeling. It should be a TLC reality show, uh, sort of like house Hunters or you know those renovation shows, but they renovate your bones. Yes, exactly, I see. I see it's like, uh, your bones. See, here's the problem

with your your bones. Your bones weren't built on a good foundation. So we're gonna need to take them all out. Yeah, when I have to rip those bones out, they're not good bones. Bones bones in there that we got from crate and barrel. Oh god, we found so much asbestos in your bones. What's the resale value on your bones out? Uh? So there are cells that are responsible for breaking down your bones, and there are cells responsible for building up

your bone mouth. So these cells like to break down your bones just to build them back up like a cult. So as kids, they're actually much more building than there is breaking down, which helps us grow bigger skeletons. In fact, like by the time you turn one years old, you'll have replaced a hundred percent of your skeleton. In comparison, as adults, we only replace about ten percent of our bone tissue every year. So as adults, like, once we're done growing, which they've both you and I have, it's

all downhill from here. Um. Sadly, that breaking down and building process is pretty much at equilibrium for a while, but as we get even older, the breaking down process can sometimes outpace the building process, which is why sometimes as you get older you actually get shorter um. It can also lead to problems like osteoporosis or the weakening

of the bones. So basically you have this very dynamic construction process with your bones, and there are the two cells that are responsible are called osteo clasts and osteo blasts. So osteo clasts are like the demolitions expert of the team. They come in. They're responsible for breaking down the mineral components and collagen of your bones and releases these broken down components into the blood, which is a process called resorption,

So you're reabsorbing these minerals that you're breaking down. Then osteoblasts come in use those recycled minerals and deposited into a new layer of bone tissue, which is called ossification. It's also one of the reasons that it's important to have calcium because even though you are recycling the bone that you're breaking down, it's a lossy process, like you

lose some of the calcium in minerals. So like to help strengthen your bones so that like when they're rebuilding it, they have enough materials to build strong layers of bone. It's good to have calcium and milk or ice cream or eating animal bones. Now, I'm kidding, yes, sucking on chicken bones. That's gonna keep you strong and healthy. That's what I tell my son here, suck on this thing. And he's like going to town on the chicken bone. And and he's he's a huge child, bigger than me

nowile for an age and headsize. He sucks all the time. Oh wow, I like, yeah, that's good parenting. That's what they call it. Start like a start like a dad blog where it's just about your giant child who eats chicken bones. I don't want to be the bean dad, but it's the opposite, right, because bean dad denied his daughter sustenance of the can of beans, whereas chicken dad offers whole chickens to his son and allows the sun to go to town. No, I'm gonna make him slaughter

that chicken himself, right exactly. They got to learn be a man. Uh. Toxic masculinity is the worst thing to happen to chickens, truly, So whild bone. While routine bone regeneration is no big deal for humans, we can't regrow whole bones after like our limbs, something happens to a limb. You know, our bones can heal. You know, if you've ever had at a broken bone, you know that whole process. But if a limb is amputated, the bone doesn't just

grow back along with the whole arm. Some of our tissue does regenerate to some degree, like our skin regenerates to some degree. But again we're not growing back whole arms and so why can't we do this? While salamanders totally can. Uh. Salamanders can regrow whole body parts, bones and all if they are lost, so it's legs or tail, it can regrow. They are able to do this trick by basically turning the cells at a wound site into

embryonic undifferentiated cells. So they revert to these embryonic cells which can then uh be differentiated into any type of tissue needed. But humans and other vertebrates can't do this except when we're embryos. So, like I said earlier, when we're embryos, we can regrow limb buds because we have all of those stem cells, all of those like b sickly can be anything they want. Cells like in the lego. Remember in lego the movie to where it's like I can be anything. I want to be the thing. It's

like the cells but then they're turning into bones. Is this track? Do the kids like this? I don't know if kids like this, but I think it makes sense. Yeah, yeah, exactly, I'm I'm hip. I know the Lego movies. So also not just embryos. This is a cool trick that young children can do to certain extents. So young children can regenerate the tips of their fingers much more easily than adults can, so they can grow back the whole finger, whereas as adults, we can't grow back some of our

like the very tip of our finger. Again, don't try this at home, guys. I cannot emphasize this enough. Please don't try it at home. But yeah, children are much better at growing back the tips of their fingers, uh, because they have there. Like when you're younger, you just have more ability to regenerate because you're growing, you have

more of these undifferentiated cells. But I think, like one of the big questions is like why don't humans and other vertebrates for that matter, like have these regeneration skills that we see in salamanders who are a vertebrate, but are one of the rare vertebrates who can regrow like whole limbs or even lizards who can regrow their tails. There's like a mammal called the spiny mouse which can regrow its fingers. Actually a lot of I think a

lot of mice can actually regrow their fingers. With the spiny mouses especially interesting because it allows like whole chunks of its skin and tissue to get pulled off. It's if it's being attacked by something and then it can regrow it. So we see this in a few animals, but not in a lot of them, and especially not in big animals like humans. It it seems like a no brainer, like why wouldn't we want to regenerate arms? Clearly the biological ability to do that exists, but we

just don't have that, which seems like a downer. But uh. One of the theories is that scar tissue formation is actually a positive trait that helps quickly seal wounds. So if every wound site goes like the whole regeneration route, we may not be able to close over that wound fast enough to prevent infection. So if you have a really big wound and you're really quickly sailing it with

a scar. That may actually improve your outcome in terms of preventing infection, especially if you have a longer lifespan, like something like a sea slug or a lizard or a salamander or a mouse may have a shorter lifespan

in having and you know, are more preyed upon. So being able to have this limb regeneration is a more important evolutionary feature than to something like a human, where you know, we we have longer lives, and so if like every time we get like a wound or something, it's like this long process of regeneration, we just have this like baby arm that takes the weeks and weeks to grow back, may actually be more difficult for us

to survive. Another issue is that regeneration of huge amounts of tissue can actually increase the risk of cancer because every time you have cell replication, there's a chance, very very tiny chance of a mutation. But every time you like spin that wheel, you may get a cancerous cell um. So like if you have a whole limb regenerating versus just like some of your skin healing, that's mean you're rolling the like cell mutation die a lot more so

it may increase the risks of cancer. So like again, like if you know, these kinds of traits would have started popping up much earlier in our evolutionary tree, but it would make sense if like our ancestors, it's like they are starting to get longer lifespans and they're bigger, and so like that playing with that number of cells ended up just like if you were regenerating things, it would maybe end up giving you cancer before you know it could serve you any purpose. Right, that makes sense.

They never would have thought that being able to regenerate your limbs could give you cancer. So I'm glad. I'm glad devolution for sparing us that particular indignity. Thank you. Which is the thing about wolverine, like he should be riddled with tumors. Yeah no, no, no no, no no, but wolverines, uh powers killed cancerselves. They don't know. It's so called salamanderine. I think that's not as cool looking. And he wouldn't have the claws. He would just he wouldn't have legs.

He just kind of screwed around. Just have legs. They do. They're right, you're right, so trot around right there. Yeah, that would be cute, like a wolverine with little baby legs and like fascinating. What about brains? Can we regenerate brain tissue? The standard knowledge is that only children generate new brain tissue as adults are brains stop developing. Recovering from brain injuries or stroke doesn't involve growing new brain tissue,

but through the art of neural plasticity. Neural plasticity is the brain's ability to adapt by rerouting neural connections and creating new neural networks using old brain tissue. It's how you learn new things even as an adult, and proves our brains are surprisingly good at making do with what we've got. But the classic idea that we can't regenerate neurons as adult is being called into question by new research.

When adult neurons are damaged, they don't simply die. They may revert back to an embryonic state, from which point they can regenerate and create new connections. The real reason that brain tissue doesn't regrow after brain and, according to new research, is not that neurons themselves can't feel, but that the injured tissues surrounding the neurons is too damaged to keep the neurons alive long enough for them to feel.

So now the question medical researchers are tackling is how we might be able to intervene by implanting a bio scaffold in the injured part of the brain to foster neural feeling. Speaking of brains, let's talk about one of the world's brainiest aquatic mammals, the dolphins, who, as it turns out, shares more with wolverine than aquaman. Dolphins are relatively large, so they don't face many natural predators other than human boats and fishers. But of course there are sharks.

And while the conflict between sharks and dolphins is by no means one sided, dolphins are smart enough to tip smaller or younger sharks over, which stuns them allows the dolphins to mercilessly attack. Dolphins do have to worry about attacks from large sharks like bowl sharks are great whites. So what do you do when your backyard is fall of sharks? So, Dave, I think we take for granted that we don't just have to encounter sharks all the time,

You know what I mean? Well, yeah, I mean they'd have a hard time handling the surface world roller skates on roller skates, put them in a radio flyer in and pull them. They just like are in a little wagon like and then pushing it with their little flippers going I'm gonna get you, gonna get you. I'm gonna get a lot of sharks taking pitch for that, because okay, sharks literally, yeah, you get it that that shark tank isn't just a bunch of sharks. And then they have

two buttons. Button one is yes and button two is no, and then if they press no, you get fed to them. And that's you know, I feel like, you know, there was a time when you could have like these very deep cable channels where not a whole lot was on and you just leave it on. Like I wanted to extended cable channel called Shark Tank where it's sharks in the tank and every twenty minutes or so they throw chum into the tank and that would be relaxing. I think, Yeah,

I would enjoy that. Yeah, but I do love sharks, But I also love that sharks are in the ocean and not out of the ocean where I am. Um. The threat to humans in terms of sharks is always sort of over overestimated. Like, It's true that sharks do very occasionally attack people, but the simple fact is we are just not around them that much. It's very rare, and most of them, most sharks don't actually want to deal with us, like, they don't want anything to do

with us. We don't we don't taste good like. They don't seem to like how we taste like. They'll often take a bite and be like, oh no, no, thank you. So like often shark attacks are accidental, But dolphins, on the other hand, are not only potential prey, but they're also competitions. So dolphins and sharks get into fights sometimes. And if you're a dolphin, you need some strategy for living in this environment where you have a bunch of body boys running around trying trying to chomp on you.

Another bad name. Let's move a punk band, though not a metal band, you know what I mean? The boys. Um. So, dolphins seem to be able to heal very rapidly from severe shark bites and other injuries from observations, so this is a pretty new area of research. How do you study something like this? You can't just have a dolphin in a lab and then hurt it, you'd be a monster, and you go to jail. You'd go to dolphin jail

and human jail. Like I think I think everyone could agree that just like hurting a dolphin, you know, intentionally, you just go to jail, go to you know, So we can't study it without being evil in a lab setting. So it's all based on observations of dolphins. So these observations seem to indicate that they can survive what seems like it should be mortal wounds from a shark, and they don't seem to bleed out. They seem actually really

surprisingly stoic. They don't seem to show a huge pain response at least visually, and they can heal back with minimal changes to their body contour. So that means like there's not a big like crater in their body. Like if you've ever had like a nasty injury or something, you know that sometimes your skin doesn't heel back all the way to where it used to be. You can actually have little craters or or bumps or something like that.

That that's normal because like scar tissue doesn't necessarily it's not the same as the tissue was beforehand, So it's really surprising to be able to heal from a grievous like a shark bite that takes a chunk out of you and have minimal dimpling like that. Yeah, I lost some skin from like getting cut with some glass ring finger,

left ring finger, and it's healed. Did healed fine, But it's always going to be kind of dented and kind of wrinkly looking, like it's never gonna go back to how it was because it's not the same tissue, like you said, yeah, yeah, and that's you know, that's that's normal. And when you think in terms of our survival, it makes sense because you know, you don't need necessarily your tissue to look exactly the same if you're healing fast enough.

But like if you're dealing with a big, like a big chunky bite from a shark, you don't Losing all of that tissue mass would be harmful in terms of like your mobility. Especially as a dolphin. It makes sense that they would want to heal back from this relatively well. And I have shared an image with you I was. I did put a warning on it that it is

dolphin um dolphin stuff. I think I might put this in the show notes, but I will put a lot of warnings on it so people know, because it shows pretty nasty, unpleasant looking, uh, injury on a dolphin from a shark bite. And each picture is sequential. So the last picture is the healed dolphin in the first pictures, it's initial injury. And looking at this it should It doesn't look like a surve livable wound. It looks you know, this looks like a dolphin. That is, it's days are numbered.

It's horrific. Yes, if you're wondering if you want to look at it, because it's in the show notes, Uh, don't like. I feel like Katie's uh suggested a lot of truly horrible things for you after this podcast is over and I have to be the voice of reason and this dolphin Okay, okay, So don't eat chicken bones and don't look at the bad dolphin pictures. Yes, don't look at the dolphin picture. Please google dolphin injuries. No, don't do that. So you put you on a watch list.

If you do that, well I'm probably already want on one then. Oh um. But yeah, So the reason I'm showing you this is not just to you know, gross you out, although that I gotta admit maybe that's part of it, but it is to show you how incredibly good the dolphins healing is like it does. It's not that it doesn't have scar tissue. It does, definitely can see that in the last thing, but it it's healed over and not only has it healed, but it's filled

in a lot of them missing tissue. So it looks basically like like the the heel site looks like it should have been just from a few scratches, not from a shark literally taking a huge chunk out of it. Yeah, it looks like I don't know, you know, the underside of rug. You know, it's got the like the material so it doesn't slide the inside of a dolphin looks like And it's interesting you'd say that because yeah, it's

not like this super bloody tissue. And that seems to be that they're able to constrict the blood flow so they don't bleed out due to these wounds. In terms of how they're able to do this, obviously it's it's

hard to know through pure observation. There are some theories that I read in terms of like being able to prevent blood loss, it may be through similar mechanisms that help them actually dive really deep, so they can decrease their heart rate and constrict blood from their peripheral tissues into the center of their bodies for deep dives, which helps them cope with the pressures of diving without risking

the bins as they surface. But the blood constriction may also help them like not not bleed too heavily if they if it's shark takes a little nibble on them. Um, the stoke pain response is more of a mystery. It's just through observation. I don't know how they can possibly know that the dolphins not in pain. I bet it is like I don't really know, you know. It's like you can't ask a dolphin like on a scale of zero to ten, like how bad is your shark bite?

And the dolphins going like like, we don't know. Is there a way to on ter like their brain activity? Um, possibly we would have to first like figure out what their brain does while they're in pain, which brings us back to the evil scientist thing again, Right, you'd have

to torture the dolphin to But I don't know. I mean, like there's probably something more elegant, like, um, if you measure there are probably certain neurotransmitters associated with pain, like cortisol and production and stuff that's like that is a response to feeling pain is and is the body's way of trying to cope with the pain. So maybe if you like take a blood sample and measure the level of cortisol, maybe that would tell you something. I don't know.

I'm not a pain scientist, because as much as it sounds like I'm an evil scientist on the show, I'm actually not because I'm not a scientist. But um, in terms of preventing infection, that's actually maybe an easier thing to answer. Dolphin blubber which is the layer of fatty tissues and dolphins blubbers also found in whales and other aquatic mammals like deals and walruses. So blubber contains antimicrobial

and antibiotic compounds. These compounds are called organo halogens, and they contain chlorine molecules, which actually works as a disinfectant again or organo halogens. That one, No, that's a hair that's a hair band, Yeah, organo halogens. I can also see that being like a crowd rock, uh, like a craftwork kind of thing. Yeah. Yeah, like everyone's stressed as

a name punk. Yeah. And in terms of how they heal so well without excess scar tissue or dimpling, researchers suspect it may be due to better regeneration of the tissue that they may have some of that salamander esque quality of being able to have their tissue revert back to that embryonic state and then heal um and so yeah, it's I think it's really interesting that, especially to see this in such a large animal, because I feel like it's usually the smaller animals that are able to do

these amazing feats of regeneration. So having a big, highly intelligent animal being able to do this, it's like, it kind of makes me question why we're not better at it. There's a lot of things I feel like humans should be better at compared to dolphins. I'm just jealous of dolphins. They've got a lot to offer. I mean, they're cuter than us. They again care free living, don't have to pay taxes to go to the gym to stay in shape.

They're constantly exercising. They're never not exercising, they're swimming all day. Maybe we should make them pay taxes though, like why is how is that fair? This is the platform of the Republican Party. I think going forward is tax the dolphins, don't tax me, tax and have the dolphins pick up the We're gonna make the dophints pay for it. We're gonna build a wall around the ocean and make the dolphins pay for it. Before we go, I want to read a really nice listener email. Um, so this is

from Evan, and he writes, my name is Evan. He him his and I want to say I love your podcast. Thank you, Evan. I spent many years working as a Phish biologist for us FWS, working on e s A projects involved with fish. Some of the work I did for them required me reading up on some of the first written accounts on what people were finding in rivers in the Southwest. These were great biological writings that often gave us insight into a healthier stage of the river.

And it was very interesting because many of the oldest biological descriptions for fish in the Southwest also contained a portion of the writing that described how they tasted and the best way to cook them. For a group of people trying to help save endangered species, we found it very funny that the original descriptions of these often involved how they tasted. So that was a long roundabout way of letting your gifts from this episode. No, so I

think this was back. We did an episode and we speculated around, like is it okay to wonder how animals taste? Extinct animals or or other animals like tasted like dinosaurs. I think we're wondering how dinosaurs tasted. Anyways, Evan writes, so that that was a long roundabout way of letting your gifts from this episode. Know that it's okay to be thinking about how these species would taste. Uh. These days,

I have more time to listen to podcasts. The business I started drinking horn metery has me driving a lot. In your podcast is a great way to get through the miles and learn a bit while I'm at it. If Stitcher let me put up reviews, you would have a five star review from me. Keep up the good work from Evan. Thank you, Evan, really sweet, Yeah, and thank you. That is interesting to me that, Like, I mean, it's unsurprising. I guess that early biologists are like, oh wow,

a new animal, Let me put it in my mouth. Yeah, I've never once thought like what is this animal taste? Like what is a dog tast? I don't want to find out. Well, not dogs, but if if you're like if you've got like a new type of fish, it's like pink and green, it's got weird spikes and like saw blades for eyeballs, Like I don't want to know. I'd want to know, like what's it hiding? What are you hiding? What kind of delicious flavors are you hiding? Right?

Like I think Darwin ate a lot of the animals he discovered to well, you know, look, some people are afraid of research and knowledge, like me specifically. You're just you're just upset that I want to eat a bunch of undiscovered animals. I don't get what's there? What's there not to love? Keeps are normal, These are normal behaviors. These are feelings that everyone has, and it's balid. My wanting to eat iguanas is valid. I'm gonna stop king shaming and I'm gonna allow you to I know, I'm

kidding again. Oh that's what someone says when it's definitely not a king. It's not a king. Oh, it's it's not sexual in anyway when sexual. Yeah, I think that's a good way. I think that's a good place in the podcast, don't I agree. I feel like we've gotten just to the point where this is still classy. We've just we've got We've come to the line of it and like if we cross it, no, Anyways, thank you

so much for joining me today. I'm sorry for you know, um, eating chicken bones while we're recording, and for the pictures of all the weird things like self decapitation. But I hope you learned. Yeah. Absolutely, And I think in the show notes for this episode you should put time codes for every single moment when you made me sick to my stomach, just so the audience can skip ahead to the fund parties. Yeah, exactly, exactly. We will mark those down.

Day've learned never to come on, Dave learned, Katie sucks, marrilettic chicken bones. Well, where can people find you? Oh? At my house? Uh, but you mean on the internet, right, Okay, So at Dave Underscore shilling is me on Twitter? You can find out all the things that I'm thinking about at three in the morning, or just you know, jokes or promotion for all the things that I'm doing uh, please please just seek me out, find me, follow me and interact with me, because I want to be your

friend very much. That sounded that's nice, that's lovely. Um. But so people can just show up at your house, no, please don't. Uh yeah, And you can find us on the internet at Creature Feature Pod on Instagram, at Creature feet Pot on Twitter. That's f E a T, not f et. That is something very different. And if you want to write in your very own email to the show, you can write me at Creature Feature Product gmail dot com. Right in your complaints about all the chicken bone business.

That's fine, Um, don't eat them. Don't eat them? Uh, disclaimer because I don't want people writing in I try to eat chicken bone now it's lodged in my brain, all right. And then also, yeah, thank you so much for listening. If you enjoyed what you heard, please leave a rating and over review. That really helps. I read them all. It warms my heart and it helps out with the algorithm. If you didn't enjoy it, you know, you don't have to say nothing. You can't say nothing.

I won't stop you, but you you're it's Look, it's America. You can do whatever you want. Thank you to this Based Classics for the super awesome song Exo Alumina. Creature features a production of I heart Radio. For more podcasts like the one you just heard, visit the I Heart Radio appop podcast or Hey guess what wherever I'm not gonna judge you. See you next Wednesday.