WEBVTT - Autotomy: Nature's Dismemberment Plan 0:00:03.080 --> 0:00:05.960 Welcome to Stuff to Blow Your Mind from how Stuff 0:00:05.960 --> 0:00:14.520 Works dot com. Hey, welcome to Stuffs to Blow your Mind. 0:00:14.560 --> 0:00:17.800 My name is Robert Lamb and I'm Julie Todd Douglas. Oh. Yes, 0:00:18.079 --> 0:00:22.040 because we're talking about autopomy today. Um as an entreat 0:00:22.079 --> 0:00:24.840 of this and really my sort of retreated the topic 0:00:25.360 --> 0:00:28.040 was to think about the story of Beowulf and Crimple. 0:00:28.160 --> 0:00:30.680 Do you remember this right? Do? Yep? This is ah, 0:00:30.840 --> 0:00:34.960 of course, from from Beowulf manuscript that has been passed 0:00:35.000 --> 0:00:38.639 down to us from Anglo Saxon poet from eight century 0:00:38.760 --> 0:00:41.360 or early eleventh century. We don't know who wrote it, 0:00:41.400 --> 0:00:45.640 written by anonymous England's oldest work of epic literature. That. Yeah, 0:00:45.640 --> 0:00:47.879 if you've ever taken any kind of a course on 0:00:48.320 --> 0:00:52.080 Western literature, anything about that the English language, then you've 0:00:52.080 --> 0:00:54.800 probably come across Baowulf. And if you haven't, then you've 0:00:54.840 --> 0:00:59.480 probably seen any number of film adaptations ranging from well, 0:00:59.520 --> 0:01:01.760 I guess most him are pretty ridiculous because it's kind 0:01:01.800 --> 0:01:04.600 of a ridiculous story. Like the basics here, it is 0:01:04.640 --> 0:01:07.600 that you have you have this Danish king roth Car. 0:01:07.959 --> 0:01:09.959 He has this hall where him and his buddies like 0:01:10.000 --> 0:01:11.600 to hang out to drink. They have to like to 0:01:11.640 --> 0:01:13.920 have a good time. But there's a monster that lives 0:01:13.959 --> 0:01:16.280 in the vicinity that does not like to listen to 0:01:16.319 --> 0:01:19.840 all of this crap, which is understandable. Yes, Grendel is 0:01:19.880 --> 0:01:23.000 the monster, and so Grendel comes and generally tears a 0:01:23.000 --> 0:01:25.880 bunch of people apart and then disappears into the night, 0:01:26.080 --> 0:01:28.360 back to the moors. And uh. And then the next 0:01:28.360 --> 0:01:30.680 morning the king is very upset about this, so finally 0:01:30.680 --> 0:01:32.840 they bring in an expert. They bring in a monster's 0:01:32.840 --> 0:01:35.920 flayer in the form of the hero Beowulf. Beowulf is 0:01:35.920 --> 0:01:39.920 an outsider, He's Scandinavian. He's coming in and he waits up. 0:01:40.120 --> 0:01:44.039 The monster comes. Grendel comes and starts to attack. Beowulf 0:01:44.080 --> 0:01:47.320 wrestles with him, and in the in bo Wolf's pretty fearsome, 0:01:47.760 --> 0:01:49.680 and then he rips the arm off, and then Grendel 0:01:50.320 --> 0:01:54.880 wales runs home and presumably dies. And I always, I 0:01:54.920 --> 0:01:57.200 always love the monster, so I was always disappointed by this. 0:01:57.240 --> 0:01:58.960 As a kid, I'm like, oh, come on, Grendel, like 0:01:59.360 --> 0:02:01.640 I really wanted more out of you in this chump 0:02:01.760 --> 0:02:04.200 just tears your arm off. I never liked Baowulf. I 0:02:04.240 --> 0:02:06.440 don't think he's a. He's a he's a likable character. 0:02:06.480 --> 0:02:10.000 I was associated more with Grendel, so I recently was thinking, 0:02:10.400 --> 0:02:13.760 what if what if this was not a situation of 0:02:13.840 --> 0:02:17.920 my my hero grendel Um being bested, Like what if 0:02:18.080 --> 0:02:22.639 his anatomy, what if his evolved responses to a threat? 0:02:22.919 --> 0:02:25.720 What if they best at Beowulf? Of course, talking about 0:02:25.720 --> 0:02:27.720 automy here where most most of us see this at 0:02:27.760 --> 0:02:30.760 a very early age. When you catch a lizard, skink 0:02:30.840 --> 0:02:34.080 or something in your hand and what happens. The tail 0:02:34.160 --> 0:02:38.480 comes off, and children just fall apart in delight because 0:02:38.520 --> 0:02:43.280 they're like, what, let's do it again? What I felt bad? 0:02:43.320 --> 0:02:45.360 I always felt bad, for sure, That's what I meant. 0:02:45.840 --> 0:02:48.680 That's what I meant. Don't Let's not do that again, 0:02:49.040 --> 0:02:51.440 is what the kids say. And then they go home 0:02:51.639 --> 0:02:54.480 and they make their beds. Autotomy is, of course, the 0:02:54.639 --> 0:02:57.720 self amputation of a body part or tissue as a 0:02:57.760 --> 0:03:00.640 means of self defense. There's no and there's no chewing 0:03:00.680 --> 0:03:03.680 involved here, there's no sign. Uh. It's more like an 0:03:03.720 --> 0:03:08.040 injection or or better yet, a shedding, and and we're 0:03:08.080 --> 0:03:11.560 talking about tail autonomy. Uh. In the case of these lizards, 0:03:11.600 --> 0:03:15.160 which again is probably the example that is most most 0:03:15.200 --> 0:03:18.480 readily available to most people's brains, because because they drop 0:03:18.560 --> 0:03:21.280 them pretty easily, we'll get more into the lizards in 0:03:21.320 --> 0:03:24.480 the tail dropping because it is very fascinating territory. I 0:03:24.560 --> 0:03:27.040 just want to mention that I love that you have 0:03:27.280 --> 0:03:32.160 this Grendel revenge tail that you've recast it as autotomy, 0:03:32.240 --> 0:03:34.639 and uh, I'm starting to think about Grendel is the 0:03:34.680 --> 0:03:39.840 Grinch of the village. Yeah right, that's that horrible noise 0:03:39.920 --> 0:03:41.840 coming from the village below, And I would love to 0:03:41.840 --> 0:03:46.080 see a Grinch tail with autotomy in it now. Yeah. Well, 0:03:46.160 --> 0:03:47.960 you know, imagine if the Grinch story had been the 0:03:48.000 --> 0:03:49.880 Grinch going down the who Ville and then the Who's 0:03:50.080 --> 0:03:52.560 beat him up and ripped his arm off. I would 0:03:52.600 --> 0:03:54.360 side with the Grinch every time. It's like he just 0:03:54.400 --> 0:03:56.640 wanted some piece of quiet, and you guys had to 0:03:56.640 --> 0:04:00.520 be jerks about it, and you're roast beast and you're 0:04:00.560 --> 0:04:04.760 singing it's just nutty. Um. So yeah. The the regenerative 0:04:04.920 --> 0:04:10.000 powers here of some species was first discovered in seventeen 0:04:10.040 --> 0:04:14.000 forty when Abraham Trembling discovered that a polyp could regenerate 0:04:14.040 --> 0:04:17.000 its tentacle crowned head if it was amputated, and he 0:04:17.120 --> 0:04:20.120 called it hydra after of course the head renewing monster 0:04:20.200 --> 0:04:22.760 from Greek mythology. You cut off one head and to 0:04:22.920 --> 0:04:24.920 grow in its place. And of course that's the other 0:04:25.200 --> 0:04:28.560 fascinating thing about autotomy is that when the lizards has 0:04:28.600 --> 0:04:31.000 its tail, a new tail grows back. And in my 0:04:31.160 --> 0:04:34.120 version of the Grendel story that's in my head alone, um, 0:04:34.320 --> 0:04:37.920 his arm would eventually grow back. It would not quite 0:04:38.000 --> 0:04:41.479 the same we'll get we'll get into that, but yet 0:04:41.560 --> 0:04:44.080 it would grow back. We see starfish doing this. By 0:04:44.080 --> 0:04:47.000 the way, some flat warrens can rebuild their entire bodies 0:04:47.000 --> 0:04:50.159 from a single cell, which is fascinating. And I wanted 0:04:50.200 --> 0:04:55.440 to mention gecks that dropped their tails. Um. They found 0:04:55.920 --> 0:04:59.000 that it shows the tail actually shows a complex pattern 0:04:59.040 --> 0:05:02.159 of repeating move mints to distract the attacker. So we're 0:05:02.200 --> 0:05:06.839 talking for up to fifty seconds dramatic flips or lunges 0:05:06.880 --> 0:05:11.599 by this tailty seconds fifty seconds, and the gecko tail 0:05:11.800 --> 0:05:14.800 that has been self amputated makes four to eight rhythmic 0:05:14.920 --> 0:05:18.640 moves per second with one of these complex movements like flipping. 0:05:18.960 --> 0:05:22.880 Because the classic scenario here outside of children picking them up, 0:05:23.240 --> 0:05:25.560 is that the lizard is threatened by a predator, say 0:05:25.720 --> 0:05:28.600 a house cat or a snake or something, and it 0:05:28.960 --> 0:05:33.000 jettison's the tail. Tail just falls off and this and 0:05:33.040 --> 0:05:35.440 the and the the lizard makes a run for it. 0:05:35.480 --> 0:05:37.200 But you know, you don't only just want to leave 0:05:37.240 --> 0:05:40.000 the gift of the tail. You also wanted to twitch. 0:05:40.040 --> 0:05:42.640 You want it to move around as a distraction, because again, 0:05:42.680 --> 0:05:45.560 anything you can do to survive, anything that this mechanism 0:05:45.600 --> 0:05:48.280 can do to push the game in favor of the 0:05:48.520 --> 0:05:50.520 lizard of the prey. Yeah, it's kind of the MacGuffin 0:05:50.520 --> 0:05:52.159 of the plot here. So you just leave this tail. 0:05:52.200 --> 0:05:53.360 You don't want it to look dead. You want it 0:05:53.400 --> 0:05:55.080 to look alive, and you want it to look like it's, 0:05:55.200 --> 0:05:58.320 you know, something that the cat or the child in 0:05:58.360 --> 0:06:01.880 this case I suppose still wants to play with. And 0:06:02.200 --> 0:06:04.880 that's why I think it's so interesting about the fact 0:06:04.920 --> 0:06:07.760 that they are these central pattern generators in the tail 0:06:07.800 --> 0:06:12.120 itself after it has ejected itself from the lizard that 0:06:12.240 --> 0:06:15.440 allow it to to sort of regenerate itself and in 0:06:15.440 --> 0:06:18.680 some cases to the coloration of the tail is different, 0:06:18.760 --> 0:06:21.839 like Skilton. Skink is a great example because it's tails 0:06:21.880 --> 0:06:25.679 also bright blue, so if it needs to jettison this tail. Bam, 0:06:25.680 --> 0:06:27.440 it's it's not only is it is it twitching and 0:06:27.480 --> 0:06:29.640 hopping all over the place for for for a little bit. 0:06:29.640 --> 0:06:32.960 It's also a bright color. It's a nice like look 0:06:32.960 --> 0:06:36.000 here not here moves. All right, Hey, well we're gonna 0:06:36.000 --> 0:06:40.000 take a quick break and we come back more on autotomy, 0:06:40.120 --> 0:06:42.679 More on the lizards dropping their tail, and another reason 0:06:42.960 --> 0:06:46.039 that lizards and and other organisms will get into will 0:06:46.120 --> 0:06:47.760 drop a limb or a tail or some of the 0:06:47.839 --> 0:06:50.120 part of their body and make a break for it. 0:06:58.520 --> 0:07:03.000 All right, we're back out. Another reason that it appears 0:07:03.320 --> 0:07:06.000 that lizards, or at least some lizards do a little 0:07:06.000 --> 0:07:09.040 bit of the tail dropping a little. The autotomy comes 0:07:09.080 --> 0:07:13.560 down to not a general population of predators, but a 0:07:13.560 --> 0:07:16.440 single predator, because that's kind of been one of the 0:07:16.440 --> 0:07:21.120 the the existing theories about how this works with the 0:07:21.120 --> 0:07:23.560 tail dropping. So they've evolved it because they live in 0:07:23.600 --> 0:07:26.160 a situation where there are a lot of predators around. 0:07:26.160 --> 0:07:29.000 So therefore they have to have a pretty drastic means 0:07:29.000 --> 0:07:32.440 of getting away. And you'll see environments where the the 0:07:32.480 --> 0:07:35.280 lizards have more predators to deal with. The predator population 0:07:35.360 --> 0:07:40.720 is greater, and so therefore their propensity for autotomy is increased. Okay, 0:07:40.720 --> 0:07:43.280 so more roving children in cats, the more there are 0:07:43.320 --> 0:07:46.679 tail droppers, yeah, at the drop it at the drop 0:07:46.680 --> 0:07:50.320 of a hat, right, especially that hat is being wielded 0:07:50.320 --> 0:07:52.679 by a toddler. Now we're looking at a two thousand 0:07:52.760 --> 0:07:55.040 and nine study from the University of Michigan, and they 0:07:55.040 --> 0:07:58.520 were looking at, uh, particularly some lizards on some offshore A, 0:07:58.640 --> 0:08:02.720 G and C islands, and they found that the situation 0:08:02.760 --> 0:08:04.640 here with the autonomy is that the lizard is dealing 0:08:04.720 --> 0:08:08.560 with one particular superprector in the form of venomous vipers. 0:08:08.760 --> 0:08:11.280 All Right, the vipers are just eating lizards left and right. 0:08:11.360 --> 0:08:14.440 This is the main concern for these for these creatures, 0:08:14.680 --> 0:08:17.200 and they're they're finding that what happens is that if 0:08:17.200 --> 0:08:20.640 the viper bites the lizard on the tail, they jettison 0:08:20.680 --> 0:08:23.000 the tail. It's like on an episode of Walking Dead, 0:08:23.320 --> 0:08:26.040 if an individual's bit on the foot by a zombie, 0:08:26.040 --> 0:08:27.640 what do you do. You grab a hack saw and 0:08:27.680 --> 0:08:31.800 you you saw off that limb to keep the zombie 0:08:31.880 --> 0:08:34.560 illness from taking hold of the individual. Okay, So in 0:08:34.600 --> 0:08:37.120 this case, they're just getting rid of the tail. So 0:08:37.480 --> 0:08:40.120 the venom doesn't get into their bloodstream and spread throughout 0:08:40.160 --> 0:08:42.400 the rest of their bodies. Yeah, they gotta cut and run. 0:08:42.440 --> 0:08:44.640 They gotta cut their losses, and their losses in this 0:08:44.679 --> 0:08:47.920 case are the tail. So the thing about this tail 0:08:48.000 --> 0:08:52.040 dropping is that it is an engineering marvel. You know, 0:08:52.120 --> 0:08:55.320 and you have always known about this right as a child, 0:08:55.360 --> 0:08:57.720 you knew that that the lizards tail would drop off, 0:08:57.760 --> 0:09:00.280 but you probably never occurred to you like, exactly how 0:09:00.320 --> 0:09:03.120 does this happen? And if you look at this closely, 0:09:03.240 --> 0:09:06.080 it is jaw dropping. Yeah, because the basic story that 0:09:06.360 --> 0:09:08.960 probably a parent or teacher told you when you said, oh, 0:09:09.040 --> 0:09:10.760 my goodness, that lizards tail came off, and they were like, oh, 0:09:10.760 --> 0:09:12.520 it's all right, it does that as a self defense 0:09:12.559 --> 0:09:15.079 to the measure, the tail will grow back and then 0:09:15.120 --> 0:09:18.600 it can drop that tail again if it's threatened. Okay, 0:09:18.679 --> 0:09:21.079 that that's that's an acceptable story. But then when you 0:09:21.120 --> 0:09:23.360 start asking why how does that work? Like like in 0:09:23.480 --> 0:09:25.920 any human, in a even a monster like Grendel, like 0:09:26.080 --> 0:09:29.200 to imagine that happening, that like an arm coming off 0:09:29.520 --> 0:09:32.440 and then not bleeding to death and then growing back 0:09:33.160 --> 0:09:35.880 even a even a partial arm in its place, like 0:09:35.960 --> 0:09:38.440 that just seems crazy. That seems magical, right, How does 0:09:38.480 --> 0:09:40.640 that affect the organism And we'll get more into that, 0:09:40.760 --> 0:09:43.520 But in terms of the actual engineering of it, it it 0:09:43.640 --> 0:09:47.280 turns out that there are horizontal fracture planes and most lizards, 0:09:47.280 --> 0:09:50.680 not all, and lizard tales will actually detach on what 0:09:50.720 --> 0:09:53.640 we could call it is like a biological dotted line. 0:09:54.360 --> 0:09:58.480 And Jan angled in colleagues from our university in Denmark. 0:09:58.520 --> 0:10:01.439 They used advanced bio imaging techniques to discover that the 0:10:01.520 --> 0:10:05.720 tokay gecko shuts its tail along these preformed score lines 0:10:06.080 --> 0:10:08.599 in specific regions of the tail, and then this is 0:10:08.640 --> 0:10:11.800 all held together by adhesive forces at these lines, and 0:10:11.840 --> 0:10:15.840 the process of separation is independent of protein cleaving enzymes. 0:10:15.840 --> 0:10:18.560 There's a lot going on here, and there's micro structures 0:10:18.600 --> 0:10:22.840 at the ends of muscle fibers that are probably involved 0:10:22.840 --> 0:10:26.320 in the release of the tail. But what's even cooler 0:10:26.400 --> 0:10:30.080 is that that the lizard actually assists in this um 0:10:30.320 --> 0:10:34.120 cleaving of the tail by contracting muscles around the fracture planes. 0:10:34.800 --> 0:10:36.600 And we know this because we've had experiments where we've 0:10:36.600 --> 0:10:39.439 put the lizards under and we found that it's harder 0:10:39.480 --> 0:10:42.720 to get the tail off of an unconscious lizard. Yeah, right, 0:10:42.760 --> 0:10:46.200 meaning that obviously when they're conscious, they are they're aiding 0:10:46.240 --> 0:10:50.640 this effort. So it's still you know, there's still score lines. 0:10:50.840 --> 0:10:54.520 The tail is still detachable, but they have to actually 0:10:54.520 --> 0:10:57.240 have some sort of conscious wheel, some sort of reaction 0:10:57.320 --> 0:10:59.600 to actually push it off and the way that it 0:10:59.679 --> 0:11:01.760 is pushed off and in this sort of fracture line, 0:11:01.760 --> 0:11:05.040 these prescord lines. It makes uh, it makes the blood 0:11:05.120 --> 0:11:09.280 loss minimal and actually helps in terms of the healing process. 0:11:09.840 --> 0:11:13.000 And there is a book called Engineered Biomimicry. In that 0:11:13.040 --> 0:11:15.920 book they're actually saying that the principles of autotomy could 0:11:15.920 --> 0:11:19.400 be used in a bunch of places. Um, they were 0:11:19.400 --> 0:11:23.240 talking about fire protection and buildings, flow control for sewer systems, 0:11:23.320 --> 0:11:26.200 and disassembly of industrial products. So if you have a 0:11:26.240 --> 0:11:28.640 car that you need to disassemble or a washing machine, 0:11:28.920 --> 0:11:31.800 you would have fracture points for disassembly. And it's really 0:11:31.800 --> 0:11:34.160 sort of brilliant when you think about it in manufacturing. 0:11:34.640 --> 0:11:36.080 So you can think of it in terms of like 0:11:36.080 --> 0:11:38.440 what happens if the name to the individual like loses 0:11:38.600 --> 0:11:40.160 a limb out in the wild, Like what are some 0:11:40.160 --> 0:11:42.120 of the first aid things you're supposed to do, Like 0:11:42.200 --> 0:11:44.000 you want to you want to close the wound, you 0:11:44.040 --> 0:11:46.520 want to apply a tourniquet. I would say, I rip 0:11:46.559 --> 0:11:48.800 off a piece of my shirt exactly, right, and so 0:11:48.880 --> 0:11:50.760 then I'm like, I'm gonna have like a half shirt 0:11:50.800 --> 0:11:52.760 on at this point, and I've got like a six pack, 0:11:53.480 --> 0:11:56.520 and I'm rambo exactly and then I used that as 0:11:56.559 --> 0:12:00.439 a tourniquet. Yeah, So similar things happen the ring of 0:12:00.520 --> 0:12:04.360 muscles around the score lines. They essentially tie off local 0:12:04.360 --> 0:12:09.040 blood vessels to prevent bleeding. And immediately after the autonomy occurs, 0:12:09.280 --> 0:12:11.600 the skin contracts around the edge of the tail step. 0:12:11.640 --> 0:12:14.200 So it's like applying a tourniquet in the bandage. Yeah, 0:12:14.240 --> 0:12:16.800 I mean, very cool stuff. And again, this is engineering 0:12:16.880 --> 0:12:19.720 at work here, and that is why some people are 0:12:19.840 --> 0:12:23.760 very interested in in in bio mimicking it. Yes, now 0:12:24.360 --> 0:12:27.640 there's a cost, of course, of course, losing a limb 0:12:27.760 --> 0:12:30.320 is just no small thing, right, because they're going to 0:12:30.760 --> 0:12:34.040 grow the tail back or a tail back, but it's 0:12:34.040 --> 0:12:36.960 not gonna be there immediately. So you have this wonderful 0:12:37.000 --> 0:12:39.600 trick to have ad a predator, but you can only 0:12:39.679 --> 0:12:41.839 do it a few times during the course of your 0:12:41.880 --> 0:12:44.720 life because it's gonna take take quite a while for 0:12:44.760 --> 0:12:49.160 it too to grow back. We're talking months or even longer. Well. 0:12:49.200 --> 0:12:51.360 And also think about the structure of your own body. 0:12:51.360 --> 0:12:53.320 And imagine if you had a tail and you had 0:12:53.360 --> 0:12:55.240 a lot of fat stored in it, if you lost it, 0:12:55.280 --> 0:12:58.480 that would be a huge source that you had lost, right, 0:12:59.040 --> 0:13:02.120 and a food source, of potential food source for your body. 0:13:02.360 --> 0:13:05.800 And not only that, your locomotion would differ because all 0:13:05.840 --> 0:13:08.480 of a sudden, your weight is distributed differently, right. I mean, 0:13:08.640 --> 0:13:10.520 when a lizard runs, the tail is very much a 0:13:10.520 --> 0:13:12.960 factor in its movements. So you take the tail away, 0:13:13.200 --> 0:13:16.040 you're gonna it's gonna it's gonna affect movement, no doubt. 0:13:16.160 --> 0:13:18.360 And again to your point, you lose the fat stores 0:13:18.400 --> 0:13:19.760 in the tail, and then you have to so you're 0:13:19.800 --> 0:13:21.959 losing the energy you had stored away, and then you've 0:13:21.960 --> 0:13:25.640 got to use more energy to grow the tail back. Ah. Yeah, 0:13:25.640 --> 0:13:29.080 and this is really interesting. Um. This is from the 0:13:29.160 --> 0:13:32.679 Journal of Zoology. The title of this study, by the 0:13:32.720 --> 0:13:35.079 way I love it, is to cut a long tail short. 0:13:35.280 --> 0:13:39.480 A review of a lizard caudal autotommy studies carried out 0:13:39.520 --> 0:13:42.000 over the last twenty years by Bateman and Fleming says 0:13:42.040 --> 0:13:45.080 that a study of four populations of and metallicust we're 0:13:45.080 --> 0:13:48.520 talking about the metallic skink lizard, demonstrated that the population 0:13:48.600 --> 0:13:51.719 with the greatest number of tail breaks was also smaller, 0:13:51.960 --> 0:13:55.000 which could be an indirect reflection of the energetic burden 0:13:55.160 --> 0:13:58.520 of repeated caudal autonomy a caudle meaning the tail falling 0:13:58.559 --> 0:14:02.280 off and tail regeneration in this population. It ends up 0:14:02.280 --> 0:14:05.400 having effect on their their reproductive abilities. It can affect 0:14:05.480 --> 0:14:09.920 an individual's ability to socialize and or mate with other 0:14:10.000 --> 0:14:12.760 lizards because yeah, you survive, but you no longer have 0:14:12.760 --> 0:14:15.199 a tail, at least for the time being. Yeah, I 0:14:15.200 --> 0:14:18.280 think about poor Grendel going back to his layer, and 0:14:18.320 --> 0:14:23.080 maybe there are other Grendel like uh ladies, maybe they're 0:14:23.080 --> 0:14:25.480 not going to be so interested to invest their time 0:14:25.520 --> 0:14:27.400 in Grendel because I don't know. First of all, he's 0:14:27.400 --> 0:14:30.560 gonna be able to regenerate that limb, and he doesn't 0:14:30.560 --> 0:14:33.120 have a lot of time also to spend with them. Well, 0:14:33.120 --> 0:14:35.560 that's why he ended up living with his mom. That's 0:14:35.560 --> 0:14:38.240 how it happens always. But yeah, I mean, he's got 0:14:38.240 --> 0:14:40.400 to take that time in the energy to try to 0:14:40.480 --> 0:14:45.080 heal himself. And we also see that in females um 0:14:45.120 --> 0:14:47.440 and female lizards who have lost their tails that they 0:14:47.480 --> 0:14:52.360 actually produce um less in terms of their clutches of eggs. 0:14:53.080 --> 0:14:56.040 And presumably again this is because they're devoting more of 0:14:56.040 --> 0:14:59.080 their energy to regenerating that tail. And also you see 0:14:59.160 --> 0:15:03.920 reduction just in reproductive fitness in general. So, as we've said, 0:15:03.920 --> 0:15:06.360 the tail grows back, but what grows back is not 0:15:06.440 --> 0:15:09.760 going to be a perfect replication of what was lost. 0:15:10.200 --> 0:15:12.440 It's more like it's not a full size spare. In 0:15:12.480 --> 0:15:14.960 other words, it's kind of like that little donut tire 0:15:15.000 --> 0:15:16.920 that you keep in the back. You can you can 0:15:16.920 --> 0:15:19.440 put it on, Yes, now that you can actually drive 0:15:19.440 --> 0:15:21.360 down the road, but you're not going to achieve the 0:15:21.360 --> 0:15:23.720 same speed you did before. The car is gonna look 0:15:23.720 --> 0:15:25.920 a little funny, and people are going to if you 0:15:26.000 --> 0:15:27.880 take it on the interstate, people are gonna like point 0:15:27.880 --> 0:15:29.760 out their window at you and say, hey, why aren't 0:15:29.760 --> 0:15:33.640 you driving with that spare? Yeah, eventually it might wear down, right, 0:15:33.920 --> 0:15:37.600 slow you down. So let's let's look at Grendel here 0:15:37.600 --> 0:15:40.040 in his lair, right, He's got the tourniquet on there, 0:15:40.280 --> 0:15:45.040 he's trying to stem the blood flow. And um, you know, 0:15:45.320 --> 0:15:49.800 if Grendel had been a lizard, perhaps muscular rings would 0:15:49.800 --> 0:15:52.240 be helping to tie off really instead of that tourniquet. 0:15:52.960 --> 0:15:55.720 But what happens immediately after autonomy is that the skin 0:15:55.840 --> 0:15:58.440 contracts around the end of the tail stuff. So you 0:15:58.520 --> 0:16:01.480 have cells from the outer most layer of skin closing 0:16:01.560 --> 0:16:04.840 over the wound and you have new cells creating what 0:16:05.000 --> 0:16:09.320 is called a wound epidermis, and this sends chemical instructions 0:16:09.400 --> 0:16:12.840 to the other cells. And this is key. Mature cells 0:16:13.200 --> 0:16:16.200 like muscle and connective tissue cells revert to an immature 0:16:16.280 --> 0:16:20.200 mass called a blastema, and this is the thing that 0:16:20.280 --> 0:16:23.040 helps to to actually create the regeneration of that limb 0:16:23.080 --> 0:16:25.560 that was lost. And we'll talk more about that blastoma 0:16:25.680 --> 0:16:27.760 later when we talk about humans and the possibility of 0:16:27.800 --> 0:16:31.000 regeneration of our own limbs. Um. But you know, you 0:16:31.040 --> 0:16:34.160 have different species with different growth rates, and then this 0:16:34.240 --> 0:16:36.080 is a slow thing happening, and as you say, you 0:16:36.120 --> 0:16:38.400 don't always get the same sort of limb that you 0:16:38.440 --> 0:16:41.520 have before. It's a little bit more like a spirit tire. Yeah, alright, 0:16:41.520 --> 0:16:43.360 we're gonna take another quick break and when we come 0:16:43.400 --> 0:16:47.360 back more on this fascinating topic more tails dropping and 0:16:47.360 --> 0:16:55.760 in some case that you're all right, we're back. We're 0:16:55.760 --> 0:17:01.480 talking about autotomy. We're talking about shedding, jettison, dropping that 0:17:01.600 --> 0:17:03.800 pail or other part of the body in order to 0:17:03.840 --> 0:17:06.600 make a break for it. And it's the fascinating thing 0:17:06.600 --> 0:17:09.919 about this is not just lizards and amphibians that experienced this. 0:17:10.160 --> 0:17:12.119 We see it in a whole host of animals. It 0:17:12.119 --> 0:17:16.119 incurs in both vertebrates and invertebrates, and it is a 0:17:16.160 --> 0:17:19.239 measure that evolved separately in each. Right, this is kind 0:17:19.240 --> 0:17:23.159 of amazing that this is a self defense system that evolved. 0:17:23.480 --> 0:17:25.359 And if you look at stone crabs, you will see 0:17:25.359 --> 0:17:28.680 that their claws they can you know, self eject and 0:17:29.119 --> 0:17:32.160 or weaving spiders. Now, we have talked about the orb 0:17:32.280 --> 0:17:35.199 weaving spiders before. We were talking about some of the 0:17:35.240 --> 0:17:39.639 things that they do doing during sexual reproduction. Sometimes, uh, 0:17:39.720 --> 0:17:44.760 the mail or spider will be decapitated for various reasons 0:17:44.760 --> 0:17:47.200 that I won't go into right now. But it also 0:17:47.240 --> 0:17:49.720 turns out that they can drop a leg if stung 0:17:49.760 --> 0:17:52.560 by wasps. So there's like a lot of dismemberment going on. Yeah, 0:17:52.600 --> 0:17:54.239 and again it's kind of like the whole zombie thing, 0:17:54.280 --> 0:17:56.840 but by a zombie drop the leg stung by a 0:17:56.880 --> 0:17:59.560 beer wasp drop the leg because especially if you're spider, 0:17:59.560 --> 0:18:01.359 you've got you've got eight of those things, so you 0:18:01.400 --> 0:18:04.560 know if you can lose one, sure exactly. Um. And 0:18:04.600 --> 0:18:09.199 then you have something called Octo Patakias delatron squid or 0:18:09.240 --> 0:18:14.280 o delatron. Yeah, it's nice, um. And this will actually 0:18:14.400 --> 0:18:18.480 deploy its limbs sometimes not only just to to scare 0:18:18.560 --> 0:18:21.639 a predator or to get them off of the trail 0:18:21.760 --> 0:18:25.600 of the squid itself, but also to wreak havoc on others. 0:18:25.480 --> 0:18:28.520 So they're sort of like independently, they can eject one 0:18:28.560 --> 0:18:31.160 of their limbs or many of them and they're just 0:18:31.200 --> 0:18:34.640 a freak. Yeah. Yeah, So that you know this limb 0:18:34.680 --> 0:18:37.879 is coming at you and it appears like it's attacking you. 0:18:37.920 --> 0:18:41.199 And actually there's some great footage of this where you 0:18:41.240 --> 0:18:43.920 can see I think it's the boom Mic being attacked 0:18:43.960 --> 0:18:47.400 by one of the limbs. You know, that would really 0:18:47.440 --> 0:18:49.159 work in the human world. You know you're getting if 0:18:49.160 --> 0:18:52.000 you're getting hassled on the subway, just start throwing hands 0:18:52.000 --> 0:18:57.680 at them, this bloody stumped hands. Multiple. You're on Martha, 0:18:57.800 --> 0:19:01.600 our train system here in Atlanta, and you have one 0:19:02.600 --> 0:19:05.760 uh one part of your body that you can use 0:19:05.840 --> 0:19:08.840 autonomy with what do you use? Well, I'm not going 0:19:08.880 --> 0:19:10.720 to drop the legs because I need this to run away. 0:19:11.359 --> 0:19:16.440 I'm probably going to go with maybe maybe my left 0:19:16.480 --> 0:19:20.400 forearm and hand, you know, just sort of can that way, 0:19:20.400 --> 0:19:22.159 can sort of sling it off at him with a 0:19:22.200 --> 0:19:24.679 punch on the end of it if need be. Wow, Okay, 0:19:24.880 --> 0:19:28.240 I think that makes sense. Originally I was thinking that 0:19:28.280 --> 0:19:31.080 I would just eject my nose into someone's eye. I 0:19:31.119 --> 0:19:34.120 don't know that would buy me much time. Yeah, Plus 0:19:34.119 --> 0:19:35.639 you'd have to have some other like you'd really have 0:19:35.720 --> 0:19:37.800 to force that thing out. But I guess there's all 0:19:37.920 --> 0:19:41.040 there's air back there, the air cavities, nasal cavities. You 0:19:41.040 --> 0:19:44.200 could somehow some sort of propulsion system evolved there. Yeah, 0:19:44.200 --> 0:19:46.959 and you've never seen anoplew in my nose before. It's 0:19:46.960 --> 0:19:51.200 pretty impressive self defense sneeze. Yeah, that's why I try 0:19:51.240 --> 0:19:52.760 to do it in the bathroom. Uh not in the 0:19:52.800 --> 0:19:56.080 break room? All right? So what else though, when we 0:19:56.119 --> 0:19:59.560 look out into the emmal world, what else could amuse us? Well? 0:19:59.560 --> 0:20:02.920 Of course, the most amazing creature really for for from 0:20:02.920 --> 0:20:05.640 our human perspective is of course when we can see 0:20:05.680 --> 0:20:08.480 this in mammals because it's one thing for a lizard 0:20:08.560 --> 0:20:11.320 to do it. It's one thing of course slugs do it. 0:20:11.480 --> 0:20:14.000 If you listen to our episode about slugs and love, 0:20:14.040 --> 0:20:17.080 and they're various reproductive measures, it should become no surprise 0:20:17.119 --> 0:20:20.160 when you learn about a slug doing anything gross. They 0:20:20.520 --> 0:20:24.560 they're the the the inventors of everything disgusting. Sing their 0:20:24.640 --> 0:20:27.880 love darts, love darts, penises coming out of the sides 0:20:27.920 --> 0:20:30.240 of their heads, you name it. So yeah, like the 0:20:30.240 --> 0:20:33.160 the idea that they also practice autotomy not a surprise, 0:20:34.160 --> 0:20:37.280 but it is surprising when you start thinking about mammals 0:20:37.280 --> 0:20:39.000 doing it because you're a little closer to the human 0:20:39.040 --> 0:20:41.280 equation here, right, And we see this when we look 0:20:41.320 --> 0:20:43.760 at a particular road and called the African spiny mouse. 0:20:44.160 --> 0:20:47.240 That's right, because al right, you human, you Robert, If 0:20:47.240 --> 0:20:50.560 you sustain a wounds your ear, what happens, well, then 0:20:50.560 --> 0:20:52.439 my ear's gonna look funny. It's like, I'm gonna get 0:20:52.520 --> 0:20:54.400 like I can bash in the ear enough times, I'm 0:20:54.400 --> 0:20:56.679 gonna get a call flower ear. If I lose a 0:20:56.680 --> 0:20:58.320 bit of it, I'm just gonna have a little less 0:20:58.359 --> 0:21:01.000