Speaker 1: Welcome to Stuff to Blow Your Mind from how Stuff
Speaker 1: Works dot com. Hey, welcome to Stuffs to Blow your Mind.
Speaker 1: My name is Robert Lamb and I'm Julie Todd Douglas. Oh. Yes,
Speaker 1: because we're talking about autopomy today. Um as an entreat
Speaker 1: of this and really my sort of retreated the topic
Speaker 1: was to think about the story of Beowulf and Crimple.
Speaker 1: Do you remember this right? Do? Yep? This is ah,
Speaker 1: of course, from from Beowulf manuscript that has been passed
Speaker 1: down to us from Anglo Saxon poet from eight century
Speaker 1: or early eleventh century. We don't know who wrote it,
Speaker 1: written by anonymous England's oldest work of epic literature. That. Yeah,
Speaker 1: if you've ever taken any kind of a course on
Speaker 1: Western literature, anything about that the English language, then you've
Speaker 1: probably come across Baowulf. And if you haven't, then you've
Speaker 1: probably seen any number of film adaptations ranging from well,
Speaker 1: I guess most him are pretty ridiculous because it's kind
Speaker 1: of a ridiculous story. Like the basics here, it is
Speaker 1: that you have you have this Danish king roth Car.
Speaker 1: He has this hall where him and his buddies like
Speaker 1: to hang out to drink. They have to like to
Speaker 1: have a good time. But there's a monster that lives
Speaker 1: in the vicinity that does not like to listen to
Speaker 1: all of this crap, which is understandable. Yes, Grendel is
Speaker 1: the monster, and so Grendel comes and generally tears a
Speaker 1: bunch of people apart and then disappears into the night,
Speaker 1: back to the moors. And uh. And then the next
Speaker 1: morning the king is very upset about this, so finally
Speaker 1: they bring in an expert. They bring in a monster's
Speaker 1: flayer in the form of the hero Beowulf. Beowulf is
Speaker 1: an outsider, He's Scandinavian. He's coming in and he waits up.
Speaker 1: The monster comes. Grendel comes and starts to attack. Beowulf
Speaker 1: wrestles with him, and in the in bo Wolf's pretty fearsome,
Speaker 1: and then he rips the arm off, and then Grendel
Speaker 1: wales runs home and presumably dies. And I always, I
Speaker 1: always love the monster, so I was always disappointed by this.
Speaker 1: As a kid, I'm like, oh, come on, Grendel, like
Speaker 1: I really wanted more out of you in this chump
Speaker 1: just tears your arm off. I never liked Baowulf. I
Speaker 1: don't think he's a. He's a he's a likable character.
Speaker 1: I was associated more with Grendel, so I recently was thinking,
Speaker 1: what if what if this was not a situation of
Speaker 1: my my hero grendel Um being bested, Like what if
Speaker 1: his anatomy, what if his evolved responses to a threat?
Speaker 1: What if they best at Beowulf? Of course, talking about
Speaker 1: automy here where most most of us see this at
Speaker 1: a very early age. When you catch a lizard, skink
Speaker 1: or something in your hand and what happens. The tail
Speaker 1: comes off, and children just fall apart in delight because
Speaker 1: they're like, what, let's do it again? What I felt bad?
Speaker 1: I always felt bad, for sure, That's what I meant.
Speaker 1: That's what I meant. Don't Let's not do that again,
Speaker 1: is what the kids say. And then they go home
Speaker 1: and they make their beds. Autotomy is, of course, the
Speaker 1: self amputation of a body part or tissue as a
Speaker 1: means of self defense. There's no and there's no chewing
Speaker 1: involved here, there's no sign. Uh. It's more like an
Speaker 1: injection or or better yet, a shedding, and and we're
Speaker 1: talking about tail autonomy. Uh. In the case of these lizards,
Speaker 1: which again is probably the example that is most most
Speaker 1: readily available to most people's brains, because because they drop
Speaker 1: them pretty easily, we'll get more into the lizards in
Speaker 1: the tail dropping because it is very fascinating territory. I
Speaker 1: just want to mention that I love that you have
Speaker 1: this Grendel revenge tail that you've recast it as autotomy,
Speaker 1: and uh, I'm starting to think about Grendel is the
Speaker 1: Grinch of the village. Yeah right, that's that horrible noise
Speaker 1: coming from the village below, And I would love to
Speaker 1: see a Grinch tail with autotomy in it now. Yeah. Well,
Speaker 1: you know, imagine if the Grinch story had been the
Speaker 1: Grinch going down the who Ville and then the Who's
Speaker 1: beat him up and ripped his arm off. I would
Speaker 1: side with the Grinch every time. It's like he just
Speaker 1: wanted some piece of quiet, and you guys had to
Speaker 1: be jerks about it, and you're roast beast and you're
Speaker 1: singing it's just nutty. Um. So yeah. The the regenerative
Speaker 1: powers here of some species was first discovered in seventeen
Speaker 1: forty when Abraham Trembling discovered that a polyp could regenerate
Speaker 1: its tentacle crowned head if it was amputated, and he
Speaker 1: called it hydra after of course the head renewing monster
Speaker 1: from Greek mythology. You cut off one head and to
Speaker 1: grow in its place. And of course that's the other
Speaker 1: fascinating thing about autotomy is that when the lizards has
Speaker 1: its tail, a new tail grows back. And in my
Speaker 1: version of the Grendel story that's in my head alone, um,
Speaker 1: his arm would eventually grow back. It would not quite
Speaker 1: the same we'll get we'll get into that, but yet
Speaker 1: it would grow back. We see starfish doing this. By
Speaker 1: the way, some flat warrens can rebuild their entire bodies
Speaker 1: from a single cell, which is fascinating. And I wanted
Speaker 1: to mention gecks that dropped their tails. Um. They found
Speaker 1: that it shows the tail actually shows a complex pattern
Speaker 1: of repeating move mints to distract the attacker. So we're
Speaker 1: talking for up to fifty seconds dramatic flips or lunges
Speaker 1: by this tailty seconds fifty seconds, and the gecko tail
Speaker 1: that has been self amputated makes four to eight rhythmic
Speaker 1: moves per second with one of these complex movements like flipping.
Speaker 1: Because the classic scenario here outside of children picking them up,
Speaker 1: is that the lizard is threatened by a predator, say
Speaker 1: a house cat or a snake or something, and it
Speaker 1: jettison's the tail. Tail just falls off and this and
Speaker 1: the and the the lizard makes a run for it.
Speaker 1: But you know, you don't only just want to leave
Speaker 1: the gift of the tail. You also wanted to twitch.
Speaker 1: You want it to move around as a distraction, because again,
Speaker 1: anything you can do to survive, anything that this mechanism
Speaker 1: can do to push the game in favor of the
Speaker 1: lizard of the prey. Yeah, it's kind of the MacGuffin
Speaker 1: of the plot here. So you just leave this tail.
Speaker 1: You don't want it to look dead. You want it
Speaker 1: to look alive, and you want it to look like it's,
Speaker 1: you know, something that the cat or the child in
Speaker 1: this case I suppose still wants to play with. And
Speaker 1: that's why I think it's so interesting about the fact
Speaker 1: that they are these central pattern generators in the tail
Speaker 1: itself after it has ejected itself from the lizard that
Speaker 1: allow it to to sort of regenerate itself and in
Speaker 1: some cases to the coloration of the tail is different,
Speaker 1: like Skilton. Skink is a great example because it's tails
Speaker 1: also bright blue, so if it needs to jettison this tail. Bam,
Speaker 1: it's it's not only is it is it twitching and
Speaker 1: hopping all over the place for for for a little bit.
Speaker 1: It's also a bright color. It's a nice like look
Speaker 1: here not here moves. All right, Hey, well we're gonna
Speaker 1: take a quick break and we come back more on autotomy,
Speaker 1: More on the lizards dropping their tail, and another reason
Speaker 1: that lizards and and other organisms will get into will
Speaker 1: drop a limb or a tail or some of the
Speaker 1: part of their body and make a break for it.
Speaker 1: All right, we're back out. Another reason that it appears
Speaker 1: that lizards, or at least some lizards do a little
Speaker 1: bit of the tail dropping a little. The autotomy comes
Speaker 1: down to not a general population of predators, but a
Speaker 1: single predator, because that's kind of been one of the
Speaker 1: the the existing theories about how this works with the
Speaker 1: tail dropping. So they've evolved it because they live in
Speaker 1: a situation where there are a lot of predators around.
Speaker 1: So therefore they have to have a pretty drastic means
Speaker 1: of getting away. And you'll see environments where the the
Speaker 1: lizards have more predators to deal with. The predator population
Speaker 1: is greater, and so therefore their propensity for autotomy is increased. Okay,
Speaker 1: so more roving children in cats, the more there are
Speaker 1: tail droppers, yeah, at the drop it at the drop
Speaker 1: of a hat, right, especially that hat is being wielded
Speaker 1: by a toddler. Now we're looking at a two thousand
Speaker 1: and nine study from the University of Michigan, and they
Speaker 1: were looking at, uh, particularly some lizards on some offshore A,
Speaker 1: G and C islands, and they found that the situation
Speaker 1: here with the autonomy is that the lizard is dealing
Speaker 1: with one particular superprector in the form of venomous vipers.
Speaker 1: All Right, the vipers are just eating lizards left and right.
Speaker 1: This is the main concern for these for these creatures,
Speaker 1: and they're they're finding that what happens is that if
Speaker 1: the viper bites the lizard on the tail, they jettison
Speaker 1: the tail. It's like on an episode of Walking Dead,
Speaker 1: if an individual's bit on the foot by a zombie,
Speaker 1: what do you do. You grab a hack saw and
Speaker 1: you you saw off that limb to keep the zombie
Speaker 1: illness from taking hold of the individual. Okay, So in
Speaker 1: this case, they're just getting rid of the tail. So
Speaker 1: the venom doesn't get into their bloodstream and spread throughout
Speaker 1: the rest of their bodies. Yeah, they gotta cut and run.
Speaker 1: They gotta cut their losses, and their losses in this
Speaker 1: case are the tail. So the thing about this tail
Speaker 1: dropping is that it is an engineering marvel. You know,
Speaker 1: and you have always known about this right as a child,
Speaker 1: you knew that that the lizards tail would drop off,
Speaker 1: but you probably never occurred to you like, exactly how
Speaker 1: does this happen? And if you look at this closely,
Speaker 1: it is jaw dropping. Yeah, because the basic story that
Speaker 1: probably a parent or teacher told you when you said, oh,
Speaker 1: my goodness, that lizards tail came off, and they were like, oh,
Speaker 1: it's all right, it does that as a self defense
Speaker 1: to the measure, the tail will grow back and then
Speaker 1: it can drop that tail again if it's threatened. Okay,
Speaker 1: that that's that's an acceptable story. But then when you
Speaker 1: start asking why how does that work? Like like in
Speaker 1: any human, in a even a monster like Grendel, like
Speaker 1: to imagine that happening, that like an arm coming off
Speaker 1: and then not bleeding to death and then growing back
Speaker 1: even a even a partial arm in its place, like
Speaker 1: that just seems crazy. That seems magical, right, How does
Speaker 1: that affect the organism And we'll get more into that,
Speaker 1: But in terms of the actual engineering of it, it it
Speaker 1: turns out that there are horizontal fracture planes and most lizards,
Speaker 1: not all, and lizard tales will actually detach on what
Speaker 1: we could call it is like a biological dotted line.
Speaker 1: And Jan angled in colleagues from our university in Denmark.
Speaker 1: They used advanced bio imaging techniques to discover that the
Speaker 1: tokay gecko shuts its tail along these preformed score lines
Speaker 1: in specific regions of the tail, and then this is
Speaker 1: all held together by adhesive forces at these lines, and
Speaker 1: the process of separation is independent of protein cleaving enzymes.
Speaker 1: There's a lot going on here, and there's micro structures
Speaker 1: at the ends of muscle fibers that are probably involved
Speaker 1: in the release of the tail. But what's even cooler
Speaker 1: is that that the lizard actually assists in this um
Speaker 1: cleaving of the tail by contracting muscles around the fracture planes.
Speaker 1: And we know this because we've had experiments where we've
Speaker 1: put the lizards under and we found that it's harder
Speaker 1: to get the tail off of an unconscious lizard. Yeah, right,
Speaker 1: meaning that obviously when they're conscious, they are they're aiding
Speaker 1: this effort. So it's still you know, there's still score lines.
Speaker 1: The tail is still detachable, but they have to actually
Speaker 1: have some sort of conscious wheel, some sort of reaction
Speaker 1: to actually push it off and the way that it
Speaker 1: is pushed off and in this sort of fracture line,
Speaker 1: these prescord lines. It makes uh, it makes the blood
Speaker 1: loss minimal and actually helps in terms of the healing process.
Speaker 1: And there is a book called Engineered Biomimicry. In that
Speaker 1: book they're actually saying that the principles of autotomy could
Speaker 1: be used in a bunch of places. Um, they were
Speaker 1: talking about fire protection and buildings, flow control for sewer systems,
Speaker 1: and disassembly of industrial products. So if you have a
Speaker 1: car that you need to disassemble or a washing machine,
Speaker 1: you would have fracture points for disassembly. And it's really
Speaker 1: sort of brilliant when you think about it in manufacturing.
Speaker 1: So you can think of it in terms of like
Speaker 1: what happens if the name to the individual like loses
Speaker 1: a limb out in the wild, Like what are some
Speaker 1: of the first aid things you're supposed to do, Like
Speaker 1: you want to you want to close the wound, you
Speaker 1: want to apply a tourniquet. I would say, I rip
Speaker 1: off a piece of my shirt exactly, right, and so
Speaker 1: then I'm like, I'm gonna have like a half shirt
Speaker 1: on at this point, and I've got like a six pack,
Speaker 1: and I'm rambo exactly and then I used that as
Speaker 1: a tourniquet. Yeah, So similar things happen the ring of
Speaker 1: muscles around the score lines. They essentially tie off local
Speaker 1: blood vessels to prevent bleeding. And immediately after the autonomy occurs,
Speaker 1: the skin contracts around the edge of the tail step.
Speaker 1: So it's like applying a tourniquet in the bandage. Yeah,
Speaker 1: I mean, very cool stuff. And again, this is engineering
Speaker 1: at work here, and that is why some people are
Speaker 1: very interested in in in bio mimicking it. Yes, now
Speaker 1: there's a cost, of course, of course, losing a limb
Speaker 1: is just no small thing, right, because they're going to
Speaker 1: grow the tail back or a tail back, but it's
Speaker 1: not gonna be there immediately. So you have this wonderful
Speaker 1: trick to have ad a predator, but you can only
Speaker 1: do it a few times during the course of your
Speaker 1: life because it's gonna take take quite a while for
Speaker 1: it too to grow back. We're talking months or even longer. Well.
Speaker 1: And also think about the structure of your own body.
Speaker 1: And imagine if you had a tail and you had
Speaker 1: a lot of fat stored in it, if you lost it,
Speaker 1: that would be a huge source that you had lost, right,
Speaker 1: and a food source, of potential food source for your body.
Speaker 1: And not only that, your locomotion would differ because all
Speaker 1: of a sudden, your weight is distributed differently, right. I mean,
Speaker 1: when a lizard runs, the tail is very much a
Speaker 1: factor in its movements. So you take the tail away,
Speaker 1: you're gonna it's gonna it's gonna affect movement, no doubt.
Speaker 1: And again to your point, you lose the fat stores
Speaker 1: in the tail, and then you have to so you're
Speaker 1: losing the energy you had stored away, and then you've
Speaker 1: got to use more energy to grow the tail back. Ah. Yeah,
Speaker 1: and this is really interesting. Um. This is from the
Speaker 1: Journal of Zoology. The title of this study, by the
Speaker 1: way I love it, is to cut a long tail short.
Speaker 1: A review of a lizard caudal autotommy studies carried out
Speaker 1: over the last twenty years by Bateman and Fleming says
Speaker 1: that a study of four populations of and metallicust we're
Speaker 1: talking about the metallic skink lizard, demonstrated that the population
Speaker 1: with the greatest number of tail breaks was also smaller,
Speaker 1: which could be an indirect reflection of the energetic burden
Speaker 1: of repeated caudal autonomy a caudle meaning the tail falling
Speaker 1: off and tail regeneration in this population. It ends up
Speaker 1: having effect on their their reproductive abilities. It can affect
Speaker 1: an individual's ability to socialize and or mate with other
Speaker 1: lizards because yeah, you survive, but you no longer have
Speaker 1: a tail, at least for the time being. Yeah, I
Speaker 1: think about poor Grendel going back to his layer, and
Speaker 1: maybe there are other Grendel like uh ladies, maybe they're
Speaker 1: not going to be so interested to invest their time
Speaker 1: in Grendel because I don't know. First of all, he's
Speaker 1: gonna be able to regenerate that limb, and he doesn't
Speaker 1: have a lot of time also to spend with them. Well,
Speaker 1: that's why he ended up living with his mom. That's
Speaker 1: how it happens always. But yeah, I mean, he's got
Speaker 1: to take that time in the energy to try to
Speaker 1: heal himself. And we also see that in females um
Speaker 1: and female lizards who have lost their tails that they
Speaker 1: actually produce um less in terms of their clutches of eggs.
Speaker 1: And presumably again this is because they're devoting more of
Speaker 1: their energy to regenerating that tail. And also you see
Speaker 1: reduction just in reproductive fitness in general. So, as we've said,
Speaker 1: the tail grows back, but what grows back is not
Speaker 1: going to be a perfect replication of what was lost.
Speaker 1: It's more like it's not a full size spare. In
Speaker 1: other words, it's kind of like that little donut tire
Speaker 1: that you keep in the back. You can you can
Speaker 1: put it on, Yes, now that you can actually drive
Speaker 1: down the road, but you're not going to achieve the
Speaker 1: same speed you did before. The car is gonna look
Speaker 1: a little funny, and people are going to if you
Speaker 1: take it on the interstate, people are gonna like point
Speaker 1: out their window at you and say, hey, why aren't
Speaker 1: you driving with that spare? Yeah, eventually it might wear down, right,
Speaker 1: slow you down. So let's let's look at Grendel here
Speaker 1: in his lair, right, He's got the tourniquet on there,
Speaker 1: he's trying to stem the blood flow. And um, you know,
Speaker 1: if Grendel had been a lizard, perhaps muscular rings would
Speaker 1: be helping to tie off really instead of that tourniquet.
Speaker 1: But what happens immediately after autonomy is that the skin
Speaker 1: contracts around the end of the tail stuff. So you
Speaker 1: have cells from the outer most layer of skin closing
Speaker 1: over the wound and you have new cells creating what
Speaker 1: is called a wound epidermis, and this sends chemical instructions
Speaker 1: to the other cells. And this is key. Mature cells
Speaker 1: like muscle and connective tissue cells revert to an immature
Speaker 1: mass called a blastema, and this is the thing that
Speaker 1: helps to to actually create the regeneration of that limb
Speaker 1: that was lost. And we'll talk more about that blastoma
Speaker 1: later when we talk about humans and the possibility of
Speaker 1: regeneration of our own limbs. Um. But you know, you
Speaker 1: have different species with different growth rates, and then this
Speaker 1: is a slow thing happening, and as you say, you
Speaker 1: don't always get the same sort of limb that you
Speaker 1: have before. It's a little bit more like a spirit tire. Yeah, alright,
Speaker 1: we're gonna take another quick break and when we come
Speaker 1: back more on this fascinating topic more tails dropping and
Speaker 1: in some case that you're all right, we're back. We're
Speaker 1: talking about autotomy. We're talking about shedding, jettison, dropping that
Speaker 1: pail or other part of the body in order to
Speaker 1: make a break for it. And it's the fascinating thing
Speaker 1: about this is not just lizards and amphibians that experienced this.
Speaker 1: We see it in a whole host of animals. It
Speaker 1: incurs in both vertebrates and invertebrates, and it is a
Speaker 1: measure that evolved separately in each. Right, this is kind
Speaker 1: of amazing that this is a self defense system that evolved.
Speaker 1: And if you look at stone crabs, you will see
Speaker 1: that their claws they can you know, self eject and
Speaker 1: or weaving spiders. Now, we have talked about the orb
Speaker 1: weaving spiders before. We were talking about some of the
Speaker 1: things that they do doing during sexual reproduction. Sometimes, uh,
Speaker 1: the mail or spider will be decapitated for various reasons
Speaker 1: that I won't go into right now. But it also
Speaker 1: turns out that they can drop a leg if stung
Speaker 1: by wasps. So there's like a lot of dismemberment going on. Yeah,
Speaker 1: and again it's kind of like the whole zombie thing,
Speaker 1: but by a zombie drop the leg stung by a
Speaker 1: beer wasp drop the leg because especially if you're spider,
Speaker 1: you've got you've got eight of those things, so you
Speaker 1: know if you can lose one, sure exactly. Um. And
Speaker 1: then you have something called Octo Patakias delatron squid or
Speaker 1: o delatron. Yeah, it's nice, um. And this will actually
Speaker 1: deploy its limbs sometimes not only just to to scare
Speaker 1: a predator or to get them off of the trail
Speaker 1: of the squid itself, but also to wreak havoc on others.
Speaker 1: So they're sort of like independently, they can eject one
Speaker 1: of their limbs or many of them and they're just
Speaker 1: a freak. Yeah. Yeah, So that you know this limb
Speaker 1: is coming at you and it appears like it's attacking you.
Speaker 1: And actually there's some great footage of this where you
Speaker 1: can see I think it's the boom Mic being attacked
Speaker 1: by one of the limbs. You know, that would really
Speaker 1: work in the human world. You know you're getting if
Speaker 1: you're getting hassled on the subway, just start throwing hands
Speaker 1: at them, this bloody stumped hands. Multiple. You're on Martha,
Speaker 1: our train system here in Atlanta, and you have one
Speaker 1: uh one part of your body that you can use
Speaker 1: autonomy with what do you use? Well, I'm not going
Speaker 1: to drop the legs because I need this to run away.
Speaker 1: I'm probably going to go with maybe maybe my left
Speaker 1: forearm and hand, you know, just sort of can that way,
Speaker 1: can sort of sling it off at him with a
Speaker 1: punch on the end of it if need be. Wow, Okay,
Speaker 1: I think that makes sense. Originally I was thinking that
Speaker 1: I would just eject my nose into someone's eye. I
Speaker 1: don't know that would buy me much time. Yeah, Plus
Speaker 1: you'd have to have some other like you'd really have
Speaker 1: to force that thing out. But I guess there's all
Speaker 1: there's air back there, the air cavities, nasal cavities. You
Speaker 1: could somehow some sort of propulsion system evolved there. Yeah,
Speaker 1: and you've never seen anoplew in my nose before. It's
Speaker 1: pretty impressive self defense sneeze. Yeah, that's why I try
Speaker 1: to do it in the bathroom. Uh not in the
Speaker 1: break room? All right? So what else though, when we
Speaker 1: look out into the emmal world, what else could amuse us? Well?
Speaker 1: Of course, the most amazing creature really for for from
Speaker 1: our human perspective is of course when we can see
Speaker 1: this in mammals because it's one thing for a lizard
Speaker 1: to do it. It's one thing of course slugs do it.
Speaker 1: If you listen to our episode about slugs and love,
Speaker 1: and they're various reproductive measures, it should become no surprise
Speaker 1: when you learn about a slug doing anything gross. They
Speaker 1: they're the the the inventors of everything disgusting. Sing their
Speaker 1: love darts, love darts, penises coming out of the sides
Speaker 1: of their heads, you name it. So yeah, like the
Speaker 1: the idea that they also practice autotomy not a surprise,
Speaker 1: but it is surprising when you start thinking about mammals
Speaker 1: doing it because you're a little closer to the human
Speaker 1: equation here, right, And we see this when we look
Speaker 1: at a particular road and called the African spiny mouse.
Speaker 1: That's right, because al right, you human, you Robert, If
Speaker 1: you sustain a wounds your ear, what happens, well, then
Speaker 1: my ear's gonna look funny. It's like, I'm gonna get
Speaker 1: like I can bash in the ear enough times, I'm
Speaker 1: gonna get a call flower ear. If I lose a
Speaker 1: bit of it, I'm just gonna have a little less
Speaker 1: ear going on up there. You're gonna a scar tissue, yes,
Speaker 1: scar tissue is gonna build up. But if you are
Speaker 1: an African spiny mouse, it's an entirely different story here, Yeah,
Speaker 1: the crazy part here. According to a two thousand twelve
Speaker 1: studies from the University of Florida, the African spiney mouse
Speaker 1: appears to regenerate ear tissue in a very similar way
Speaker 1: to a salaman or when it regrows a limb that
Speaker 1: has been lost to a predator. That means skin, hair, follicles, cartilage,
Speaker 1: everything in the ears will grow back. It also regrows
Speaker 1: a tissue on its main body when it's injured, but
Speaker 1: not as completely as it does with the ears, so
Speaker 1: it just heals quickly elsewhere in the body, but only
Speaker 1: the ears truly regenerate. Now. Ashley W. Surfert Uh, the
Speaker 1: post doc researcher in this study punched holes in the
Speaker 1: ears of African spiney mice to figure this out. By
Speaker 1: the way, and he became with a whole punch. Uh.
Speaker 1: It doesn't say a whole. It doesn't say what the
Speaker 1: instrument was, but I would like to imagine that was
Speaker 1: the whole punch. But Cifert actually became interested in the
Speaker 1: mouse when a colleague said that it appeared to have
Speaker 1: or a waste skin that allowed it to escape a
Speaker 1: predator's grasp. And that's once ip for said U. Let's
Speaker 1: take a closer look at this and see what's going on.
Speaker 1: Hair away skin. It's very like it's like an animal
Speaker 1: designed by Clive Barker that exists, right right, um, and
Speaker 1: the researchers actually believe that it could lead to a
Speaker 1: new model system for skin wound healing and tissue regeneration
Speaker 1: and humans. And that's the thing, right, And you see
Speaker 1: this a lot. It's It's often what pops up at
Speaker 1: the very end of any study into autotomy is that
Speaker 1: the researcher will say, and hey, sometime in the future,
Speaker 1: this might help humans heal because it's a nice light.
Speaker 1: It's a nice way to end your study into lizards
Speaker 1: dropping their tails on some remote islands somewhere or in
Speaker 1: the backwoods of Georgia. We yeah, and we love that stuff.
Speaker 1: We love a little like naval gazing future gazing and uh.
Speaker 1: And if you can spin that out of a out
Speaker 1: of a study, I'm all for it. And it also
Speaker 1: works great in the headline, right, lizards may hold the
Speaker 1: key to regional ration in humans in the future, or
Speaker 1: something to that effect. But right now, as humans, when
Speaker 1: when something happens to us, we're just talking about scar
Speaker 1: tissue and and that's pretty much that um. But getting
Speaker 1: the healing process to the point of actually creating a
Speaker 1: new limb would require that blastema that we were talking about,
Speaker 1: that the muscles and the connected tissue cells. Reverting to
Speaker 1: an immature maths that is key. And that's where researchers
Speaker 1: are really looking into this and saying, you know, why
Speaker 1: don't mammals like us have this regenerative power? Well, why
Speaker 1: don't we have it? Though? The answer to that, of
Speaker 1: course is simple, it's why the same the same answer
Speaker 1: is why do we not have shells? Why do we
Speaker 1: not have uh, you know, crazy clause ripic banks apart?
Speaker 1: Because we have evolved as a species depended more upon
Speaker 1: our brain power and ingenuity as opposed to any kind
Speaker 1: of built in weapons or defense measures that we have.
Speaker 1: Show we can point to our neo cortex and go,
Speaker 1: you don't have that, do you? Yeah, Like, the closest
Speaker 1: thing we have to this really as humans is the
Speaker 1: clip on tie you and go grab me by my
Speaker 1: neck tie and uh and and and brutalize me. No,
Speaker 1: because the tie comes right off, just like a lizards tay.
Speaker 1: Hair extensions. Yeah, hair extensions another example. Oh you think
Speaker 1: you have me by the hair note, note comes right off.
Speaker 1: But what's standing in the way, what's standing in the
Speaker 1: way of us adapting this for humans, because certainly researchers
Speaker 1: are all already looking at the genetic basis for regeneration
Speaker 1: in the in lizards and then and then inevitably in
Speaker 1: African spinding lines as well, looking at what enables these
Speaker 1: limbs to regrow. And we know enough about gene tinkering
Speaker 1: at this point. I mean, it's a fairly new ability,
Speaker 1: but we know enough about it to to realize, hey,
Speaker 1: it's at some point we can start combining a little
Speaker 1: A with all it a little from from column B
Speaker 1: and potentially have some sort of human ability for regeneration.
Speaker 1: What's standing in the way, besides the fact that you
Speaker 1: know it's scar tissue and boom and nothing else happens,
Speaker 1: is really trying to understand how that process works. And
Speaker 1: to do that, you've got to have the right sort
Speaker 1: of species at your disposal. And in this case, the
Speaker 1: right sort of species is a salamander. And it takes
Speaker 1: a long time for that tail to regenerate, So it's
Speaker 1: not like you're collecting a massive data here. Yeah, it's
Speaker 1: slow to grow, and salamanders are not good laboratory animals. Also,
Speaker 1: salam energyenomes are really bloated. It turns out they have
Speaker 1: ten times the amount of DNA as humans, and no
Speaker 1: one's ever really syncus them all the way. And we
Speaker 1: only recently developed the means to hack salamander genes. And
Speaker 1: we're talking recently. There's two thousand nine that we've really
Speaker 1: come into that. Uh and uh, you know another thing
Speaker 1: here about this is that not a lot of people
Speaker 1: are looking into it. It's not necessarily on everyone's radar
Speaker 1: because we have a few other stars in the classroom
Speaker 1: when it comes to uh, potential for enormous impact on
Speaker 1: human health and repairing lost limbs, damaged organs, etcetera. Well,
Speaker 1: you're actually seeing strides and stem cell regeneration and particularly
Speaker 1: when you're talking about growing organs, So it would make
Speaker 1: sense that you would look more toward that column for
Speaker 1: hope of limb regeneration or limb growing. Really. Yeah, and
Speaker 1: also you have to consider the the the things we
Speaker 1: don't know about regeneration and these particular items were brought
Speaker 1: to our minds by ed Young, who wrote a BBC
Speaker 1: article called will we ever regenerate Limbs? He pointed out
Speaker 1: the limb won't regenerate if the nerves inside don't start growing.
Speaker 1: But what exactly do the nerves do? He he asked,
Speaker 1: when the cells in the stump rewind their fates to
Speaker 1: become that blastema, how far back does it go? And
Speaker 1: then he pointed out how do the cells of the
Speaker 1: re growing limb know where they are? And how do
Speaker 1: they take the right shape or or how do they
Speaker 1: make a working limb and not just a useless, deformed,
Speaker 1: you know limb on the end of the art. Yeah,
Speaker 1: that's pretty fascinating that so specifically it knows what to
Speaker 1: recreate the cells. So. Ed Young also said that perhaps
Speaker 1: the reason why humans don't have this um of our
Speaker 1: sleeves is that the same checkpoints this is equipped from him,
Speaker 1: the same checkpoints that stop ourselves from growing uncontrollably into
Speaker 1: tumors might also stop a blastema from forming. That kind
Speaker 1: of makes sense, right, You don't want any sort of
Speaker 1: abnormal growth happening. So perhaps and humans it's just the
Speaker 1: stop gap measure to making sure that uh, something isn't
Speaker 1: becoming a malignant form. Yeah, And you don't want to
Speaker 1: like enable humans to regenerate just so that they can, uh,
Speaker 1: you know, every time I get the flu, I start
Speaker 1: growing random arms out of my back. That would be
Speaker 1: very helpful actually, but they'd be like little baby arms.
Speaker 1: What am I gonna do with those? Um? Just hold
Speaker 1: on the notes, game, right, certain to seem better? Right?
Speaker 1: All right? So a career argument that Ciphert makes. Cypfer
Speaker 1: of the African spiny Mass says that human diseases from
Speaker 1: heart attacks to cirosis involves some sort of fibrosis where
Speaker 1: the body deals with injuries by laying down connective tissue.
Speaker 1: He says, fibrosis is the antithesis of regeneration. So if
Speaker 1: we can understand how animals avoided it could tell us
Speaker 1: how to stop scar tissue from building up on our
Speaker 1: vital organs, which can be very problematic. So you're saying
Speaker 1: that this is still something that we should study, and
Speaker 1: we should still try to figure out how it happens
Speaker 1: and why it happens. Seaford also pointed out that small
Speaker 1: salamanders took four hundred days to grow back a leg
Speaker 1: and and and that's less than four millimeters across, and
Speaker 1: the largest ones needed more than a decade to finish
Speaker 1: the job. So Seaford argued that even if a human
Speaker 1: could grow a limb back with a with a with
Speaker 1: a similar adaptive feature, it might take fifteen to twenty years. Now,
Speaker 1: if one loses a limb, that might be an acceptable
Speaker 1: wait time. That's the thing. I mean, it's not in
Speaker 1: terms of like treatment on an illness. Fifteen to twenty years,
Speaker 1: that's that's a long treatment time. But think of the
Speaker 1: things that that you would you would go on that
Speaker 1: waiting list for and someone was like, hey, you're uh,
Speaker 1: you know your your your lungs is not doing that great.
Speaker 1: Can grow your new one, uh, you know, nice fresh one,
Speaker 1: but it will take fifteen to twenty years or your game.
Speaker 1: So yes, I think, especially if the Aubrey de Gray
Speaker 1: model of life expectancy actually plays out, So if we
Speaker 1: actually do see a d four hundred year old people
Speaker 1: who are needing um different body parts, fresh ones that
Speaker 1: are that are operating in a way that actually gives
Speaker 1: them a better quality of life experience than yeah, maybe
Speaker 1: fifteen to twenty years, that sent a big deal. Yeah,
Speaker 1: you says, say you lose an arm fifteen to twenty
Speaker 1: years to regrow that arm. I think that makes sense.
Speaker 1: That the question that arises is if we get to
Speaker 1: the point where you can use some sort of gene
Speaker 1: tinkering regeneration to regrow that arm of the course of
Speaker 1: a couple of decades um is it will it? Will
Speaker 1: it be a faster option by that point just to
Speaker 1: grow it in a lab to to to use stem cells,
Speaker 1: use a tissue growing techniques to develop a new arm
Speaker 1: and simply transplant that onto the body. Well, that's the
Speaker 1: That's a great question because we already have the scaffolding
Speaker 1: in place to essentially grow the structure. So yeah, it'll
Speaker 1: be really fascinating to see in a decade from now
Speaker 1: what the answers to these questions are. I mean, I
Speaker 1: think I'm gonna go wisdom, so I'll have to say
Speaker 1: regeneration yea, or we'll we see some of the combination
Speaker 1: of the two, whereas like you grow me something in
Speaker 1: the vat and then you're also doing some sort of
Speaker 1: regeneration technique to make the like the stump meet the
Speaker 1: new arm. Okay, I'm pondering it. That was a pondering
Speaker 1: silence all right, think it over and and silence is key,
Speaker 1: especially if you live out there in the wild, perhaps
Speaker 1: near some sort of mysterious moore. Uh, you don't want
Speaker 1: to party two out. You don't want to play this
Speaker 1: podcast too loud, because there's a creature out there potentially
Speaker 1: that may want to come and tear you limb for
Speaker 1: limb and possibly leave one of his or her own
Speaker 1: limbs if things get a little too rally, right, Yes,
Speaker 1: the Grinch Grindle. I wonder if there's some connection there.
Speaker 1: I've never thought of it. There's got to be some
Speaker 1: sort of subconscious thing going on there. Uh. There was
Speaker 1: an old episode of Tales from the Dark Side in
Speaker 1: which a Grinch like creature comes and like slays the
Speaker 1: mother and father who don't believe in Christmas. That's just
Speaker 1: a long tradition there, because then you have, um, what
Speaker 1: is the anti Santa clause? Cramp Crampas is very much
Speaker 1: like the Grinch. So yeah, Crampus, yes, not eating in
Speaker 1: the first draft at least alright. Well, on that note,
Speaker 1: let's call over the robot and uh do at least
Speaker 1: one listener mail just to keep the robot happy. All right?
Speaker 1: Here here comes one from our listener in response to
Speaker 1: the Creepy Music episode the Uncanny Music episode The Science
Speaker 1: of Uncanny Music. We heard a lot from you guys
Speaker 1: on this one, and you know, sadly we're not going
Speaker 1: able to read all the responses, but receive a lot
Speaker 1: of great content. Uh. In this one, listener says, Hi,
Speaker 1: my name is Richard Brunner, and I was just writing
Speaker 1: in to say your episode about creepy music is timely,
Speaker 1: and not just because Halloween is coming up. I just
Speaker 1: finished working as an assistant on a film score for
Speaker 1: a horror film last week out in Los Angeles, so
Speaker 1: it's interesting to hear the podcast about horror music. It
Speaker 1: definitely does add a lot to the scary nature of
Speaker 1: horror films. I was working as a music production and
Speaker 1: UH and on sheet music preparation for the recording session,
Speaker 1: so I didn't have much to do with the actual
Speaker 1: writing of the music on this film, but it was
Speaker 1: certainly an interesting experience working with the composer and seeing
Speaker 1: his music come together and how much the music and
Speaker 1: sound effects enhance the horror of the horror film. Also,
Speaker 1: I want to say that I wanted to say congratulations
Speaker 1: on three years of the podcast, so far. I've been
Speaker 1: listening to many of the episodes over the past year
Speaker 1: or so, and I always enjoyed them. Hopefully there will
Speaker 1: be many more years to come. Alright, very cool. It's
Speaker 1: interesting to hear it from that firsthand account, watching the
Speaker 1: process come together. Yeah, and and of course I always
Speaker 1: love hearing from listeners and finding out what the neat
Speaker 1: and interesting hobbies, passions and jobs end up, you know,
Speaker 1: opposing the live So to his point, three years of podcasts,
Speaker 1: if you want to find those, if you want to
Speaker 1: experience all three years of Stuff to Blow Your Mind
Speaker 1: and uh in the earlier podcast that it evolved out off,
Speaker 1: then you can find them at stuff to Blow your
Speaker 1: Mind dot com. That means episodes that you cannot find
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