The Alien Biped

You have macropods, kangaroo rats in my spring hair hopping, my pangolins, and of course homing a apes um much which includes ourselves and sometimes scientists, you know, make the distinction between facultative and obligate bypeds, though this isn't a standard distinction, suffice to say they're creatures such as the human flightless birds, and to draw on a prehistoric example, the t w rex, that have no real alternative to bipedal movement. I mean, I can crab walk around, Yeah,

I wouldn't. If if you're crab walking, you're still bipedal unless you can grow some crab legs. It depends which version of the crab walk. Are you're talking, you're talking about where you're I'm talking where you know, you lean back and you go on all four your belly up in the air. Because there's also the Zoidberg walk, where you walk from side to side. That's a good one, but that's not that that would just be bi Zoidberg is a biped No no, no, no, I mean the

the Exorcist down the stairs. Well oh yes, yes, okay, well that that would count, but I fully grant you I probably wouldn't get around very quickly doing that all

the time. Other creatures, of course, are capable of bipedal locomotion, but only employed under certain circumstances, like, for instance, a lemur dancing you know, sort of prancing sideways across a clearing between two trees, a giant ground sloth in in in old and olden days, rising up to reach higher branches, or or one of my favorites, a cat standing on its hind lay eggs to better view pray or something of interest. This is always a creepy, weird side if

you're lucky enough to witness it. Oh but it also can be very cute when dogs stand on two legs to to get up there closer to the treat that they want. Oh, yeah, it's adorable. It's yeah. When dogs do it, it's adorable. When cats do it, it is it's a little unsettling, like they've suddenly become tiny people, like they've been people all along, um or that's my

read on it. Now. When it comes to the hominans, which again includes humans, the oldest evidence of bipedal movement in a hominant species was probably six million years ago. This would have been the selmthropists, and there's some dispute over this, but any rate, we were mostly bipedal by

say four million years ago. We had a curved spine by two point five million years ago, and it altered our hip support by one point nine five million years ago, and we were fully bipedal by the time of Fomo erectus, with signature pelvis and thigh bones evident in the fossil record. The legs lengthened over time, allowing for longer strides everything that would enable the ministry of silly walks to do

its thing. Yeah. Now, some of what we know about the posture and gate of our ancient ancestors and their close relatives has to be inferred indirectly. I mean, you can get a pretty good idea from like the shapes of bones and stuff that that will tell you a lot. There's other there's other evidence that's very direct. A great piece of early direct evidence for bipedality is the fossil formation known as the Late Totally Footprints. So, Robert, have

you have you seen what these look like? I think I have everybody very cool in In nineteen seventy six there was a team working with the paleontologist Mary Leaky, and they discovered a collection of fossilized animal tracks in late Totally Tanzania, which is south of the Old Duvai Gorge. And the tracks were preserved in what had been a soft bed of volcanic ash about three point six million years ago or three point three point six three point seven uh and it had hardened and been preserved for

us to discover in the twentieth century. And then so after these tracks were initially discovered, in nineteen seventy eight, Paul Able, a colleague of Leaky's, discovered that the formation also contained a twenty seven meter or about eighty eight foot long trail of ancient hominin footprints in addition to the other animal footprints, probably made by Australian Epithecus afarensis, the species to which Lucy belonged, And there were about

seventy hominin footprints at all in all in this formation. And so the thing about these footprints is they're quite clearly bipedal. You know, you're not seeing four legged movement, and somebody was just walking on two feet through this volcanic ash. The prints i've read are space close together, meaning a short stride might mean short legs. And the prints also show a big toe in line with the foot rather than opposed to the foot, as you see

in arboreal apes. So like you know, your human big toes go straight out, the arboreal apes have more kind of a toe thumb, like a big toe thumb, uh, that they used to climb trees and grab hold of stuff. And also their footfalls apparently went heel toe, just like ours tend to. So by about three point six million years ago, we we've got direct evidence that our ancestors

and their close relatives were walking on two feet. Uh. And I also can't help but mention I've read supposedly there's this story of how the prints were discovered because one of Leaky's colleagues, a paleo anthropologist named Andrew hill Uh, stumbled across the fossil formation when he and another colleague

were running around throwing elephant poop at each other. Oh well, you know you gotta keep it lighthearted on the dick, right, So, um, like you said, we we know all of this based on mostly fossil remains, and by that this, you know, we're looking at the bones of our ancestors and observing what the gradual shift to bipedalism did to us. And it certainly certainly came at a cost. Yeah, now, to be sure it was it was worth it, I guess.

I mean. It made it easier for us to pick up fruits and pick up pick from a low line branches. It gave us free hands for carrying food and also very importantly carrying tools, carrying our young as well. It allowed us to rise up and appear larger and more fearsome to our enemies. Are many enemies of the wild. This is something that I think we often don't think about.

But unless you're being instructed on how to react to a bear in the win the wild, you know, they say, make yourself as big as possible, and certainly there are other animals that do just the same thing, but that's one of the strengths of being able to at least rise up on two feet. Yeah, now you can't know this for sure, but I tend to think that bipedalism is a sort of necessary precursor to advanced tool using intelligence.

I mean, you see some use of tools in quadrupedal apes, but the fact that the fact that you're walking on two feet gives you free hands, and having free hands, it seems like suddenly you've got much more incentive to be using them for all kinds of stuff. Well, it's interesting when you think about the animals that do display some form of tool use. I mean, certainly you have the the apes, which are going to more or less

aligned with the human experience of tool use. But then of course you have like the corvids uh and uh and a few other birds that that also use tools. Now, obviously they are engaging in bipedal ground movement. Their wings are tucked away, but it's perhaps and it's a slightly different situation with birds because those wings do have a purpose. Uh, They've just specialized their their their beak functionality, and I've learned how to use tools with that. The same is

truy of dolphins. You know they're using when they engage in tool use, are using their snout um octopi slightly different situation they have they have They have a wide variety of limbs and are not necessarily gonna become bipedal anytime soon. So anyway you shake it the back to the human scenario, it helped us expand our range. It It definitely played a part in our our ascension or dominance, certainly our ability to invent things and expand, but we

also paid a price. We had to distribute all of our weights on two limbs, resulting in all sorts of painful experiences such as a lower back pain, slip discs, arthritis in the lower body, fallen arches. Our spines are ultimately just kind of weird. We evolved wider hips and stronger knees to kind of cope with it to a certain extent. But this is the reason that roughly of adult humans will experience back pain in their lives. I would say one of the biggest anatomical drawbacks is that

we can make finger guns at each other. I mean that that is a true blow to the species you mean, I mean the beneficial kind where like kids playing cowboys and Indians or whatever on the playground, know the like the like catch you later, bro Okay. So also it also affected the way that we give birth and uh and this is a I have to say, this is a topic that we could easily have devoted an entire episode.

There's a lot of scholarship and debate on exactly how the modern human birthing scenario pans out towards prehistoric examples, but the move towards the bipedal form changed our skeletons. This affected the pelvis. Most primates have a pretty straight birth canal, but hominans soon boasted a narrow, distorted, kind of fun house tube of a birth canal. The offspring had to twist and turn in order to pass through. This is true of our our ancestors. But our bodies

continued to evolve. We became taller, we grew larger brains. That means meant bigger brained babies having to make it through that twisting tunnel. Everything became tighter. Child birth became a potentially more dangerous affair, because it also means giving birth to a child an earlier stage of its development in order to actually break it free from the confines of our bipedally twisted bodies. Now, again, there's a lot

more to this. Scientists have gone back and forth on the so called obstetric dilemma, but bipedal evolution certainly changed things. All right, I think we should take a quick break. We will be right back to discuss why bipedalism evolved in humans. Thank alright, we're back. So this is a big question because certainly we can point to all of these like the pros and all the cons, but like, what is the driving force right right now? What caused

our our ancient hominin ancestors to go on two legs? Primarily, why did our ancestors become bipetle And this is an ongoing debate. We know at some point we transitioned from mostly four footed gate to a mostly two footed gate, but why did it happen and what type of pressure selected for this? So, first of all, when answering questions like this, it's often hard to be certain, right, you know,

we only have the evidence we can find. Fossil evidence helps, but it's hard to like run new experiments to test this. We you know, we only have the fossil finds we have and can only draw the conclusions we can draw from them. And there have been all kinds of answers

over the years. So for a long time, consensus seem to be that bipedalism was an adaptation to a change in our primary habitat, as our ancestors moved down out of the trees into a flat grassland, perhaps driven by changing climate, like changing climate killed off forests and left these you know, savannahs with tall grasses in their place, or these creatures just moved down into the savannahs to

follow food sources or something. In this case, uh, these hominins needed to stand up to see over the tall grass. And this explanation is not still favored. This has fallen out of favor among experts, and one reason is that climate history analysis and physical fossil evidence indicate that we were becoming bipedal at the same time that we were still adapted to climbing and living in trees. And I

think there are multiple lines of evidence supporting this. It appears that at some point our ancestors were both like living in forests and climbing trees, but also having skeletons. That's supported bipedal walking gate. Also, it's worth pointing out that plenty of other animals that occupy areas with tall grasses tall grasslands do just find staying on all fours right. They don't need to stand up to see over the grass in order to survive. Like grassland baboons today are

still quadrupedal. So that used to be what people thought, but that is not no longer the main hypothesis. So another theory that is popular with the public but not with scientists in the relevant fields is the much much beloved aquatic ape theory. Oh yes, we talked about this um last year. Yeah, and our Aquatic Humanoids episode. We concluded that there's not really any good evidence for this.

There's no direct fossil evidence for whatsoever. And the indirect reasoning that causes people to think that there's evidence for this is, uh, it's just not very good. But we should mention it because this is bound to come up whenever people address bipedality in its origins. I think it's just because it's fun to imagine, maybe, and because it's

unconventional that makes it more interesting to people. Basically, it says that the explanation for the main phenotypic variations between us and our closest ape relatives is that our direct ancestors briefly evolved to become water dwelling primates so sort of like fishmen and uh, and then moved back to dry land after that. And under this theory, bipedality evolves because we need to keep our heads above water when

we're waiting around in search of shellfish for food. All Right, it would be kind of like the idea that that we became bipedal because we didn't want to get our t shirts wet, you know, I mean, it's it's not that bad, but yeah. So this was first proposed by Alistair Hardy, and it was mainly developed by somebody named Elaine Morgan. And in short, Morgan says, look, we're the only mammal that consistently walks on two legs, but some four legged animals can occasionally stand up on two legs

and wind. Do our closest stape relatives walk on two legs? Well? She claims there's only one circumstance when they always walk on two legs, and that's when they're waiting in water. I see some pretty clear evidence running counter to this assertion, just in publicly available video like primates. You look this up. Primates sometimes stand up on two legs for all kinds of reasons while carrying objects and moving around with them

during dominance displays to reach something like they don't. And they also, on top of that, don't always stand up when waiting in water. I found video of guerrillas waiting around in water, and they tend to stay on all fours. So if the classic explanation about seeing over the grass is probably wrong and we don't put any stock in the aquatic ape, what is the real explanation? Of course, we still don't know, but there are a lot of

competing theories. Maybe there was a selection pressure on having free hands, so maybe some of our ancestors began carrying or throwing things, and for some reason this got started, and then there was a great survival or reproduction advantage for the ones that did this more and more of the time. So being able this comes back to the examples of being able to carry ones young, being able to carry food that you've gathered, or being able to carry a tool or a weapon, say a nice you

know jaw bone for smacking the other epe creatures around. Well, I mean a big one I've seen suggested actually is throwing, Like if if we evolved somehow a throwing hunting strategy where you would throw objects, that this could have spurred bipedality or some bridge to it. Another thing I was reading about in a BBC article is that recent research has suggested that perhaps partial bipedality helped these hominins adapt

to rocky, uneven terrain in geologically active areas. Essentially that our ancestors were not only tree climbers, but rock climbers, and this encouraged them to take on some traits that bridge the gap to bipedalism. Another is, I guess sort of the least the least interesting is an idea but has seems to have a lot going for it, And it's simply that a certain kind of bipedalism in tree dwelling life became useful, as it is in many orangutans today.

Like you can look at orangutans living in the trees that walk around on two feet, like they'll reach up and grab branches with their arms over their heads while walking around on other branches with two feet, it's just a great way to anchor yourself between a lower and upper branch. So there are a lot of competing theories. I mean, I know there are other ones we didn't even cover here, but this is this is an unsolved question. We still don't know the answer now anyway to shake it.

We were not the first bipeds, not even close. I already mentioned the t rex, you know that, that famous the famous Cretaceous period, the carnivore Cretaceous spirit, of course, banned hundred forty five million years ago to sixty six million years ago. And this again, it's just an animal that could scarcely be more of a biped you know,

those tiny little arms. And of course he or she is just one of the many therapods that roamed the prehistoric Earth, and in many cases not not not just roamed it, but ran after their prey, running a key advantage of their bipedal morphology. But even they, it seems we're not the first. Um there's a two hundred and ninety million year old fossil of a species that is

dubbed ood Obama's Kersaurus. This is a creature that was very lizard like it seems, and it's a probable appearance, had short fore limbs, relatively long tail and high and also relatively long hind limbs. So these are kind of the hallmarks of of a bipedal creature. But the other curious thing about it is that it seems to have been a herbivore rather than a meat eat or like

the theropods. Therefore it probably palin. I just think it probably depended on bipedal running to flee from quadrupedal danger. And on the subject of dinosaurs and quadrupedal and bipedal arrangement, I found a two thousand five article in Astrobiology magazine that brings up a species that is dubbed Masso spondulous. And this is a pro sorrow pod now Sara pods

as everyone remember that. You know, they're the giant Diplodocus Brachiosaurus style kind of creatures, you know, big, enormous quadrupeds. It just enormous, just ponderous creatures. The pro sauropods, unlike their descendants, they could rise up on their hind legs and go after food bi petally. So back in two thousand five, University of Toronto at Mississaugua thiss ut M

biology professor Robert Rice. He looked at an embryo of one of these massospondulous creatures and he found the thing was that it looked like a four legged saara pod. So he hypothesized that it would have grown into a full bipedal form as it matured. Uh this is what he told Astro Astrobiology magazine quote. Because the embryo of massospondos looks like a tiny saua pod with massive limbs

in a quadrupedal gait. We proposed in our paper that the sauropods gate probably evolved through a phenomenon called ptomorphosis, the retention of embryonic and juvenile features in the adult. So this is interesting cause we're talking about a creature that potentially adapted bipedal, the bipedal gate, but then left it behind. Uh paedomor morphosis. By the way, it's it's

something we see today in various amphibian speeches species. But for for these saua pods and for the true sauropods, it would mean that they were essentially man babies of the prehistoric world, like they simply no longer had to grow up like they were the biggest forest eating dumpsters on the planet, and therefore they really didn't have to augment their more or less larval form anymore. You know, I have often wondered something when looking at bipedal therapod

dinosaurs like the t rex. Just look at that powerful lower body and then the tiny little baby arms out front. If this dinosaur fell down or even just you know, went to have a little lie down in the meadow, how did it get back up. I'm not saying it would be impossible, it just seems very awkward. Of course, we're by peedle and we can get up from the ground, but we have long arms and strong upper bodies to help us. Try lying down on the ground and then

getting up without using your arms at all. You can probably do it, but it's not so easy, is it? And the t rex probably has an even lower relative center of mass than you. So what's going on? Like, was it this much of a struggle for the t rex every time it had to get up from the ground. That's a great question. Well, I've been wondering this for a while. I finally looked it up. There's actually a really good explainer on this in Scientific American provided by

the paleontologist Gregory M. Ericson of Florida State University. And so here's what Erickson says. First of all, there has long been a dispute over exactly what the t rex is tiny four limbs were four uh maybe you know. One idea says, maybe they're just a vestigial, meaning they're actually not good for much of anything at all, and they only existed in diminished form because the rex hadn't fully lost them yet. And then the next idea says, well,

maybe they're grasping arms used in copulation. And then the next idea says, maybe there's some sort of meat hook for feeding chunks of flesh into the mouth. Though this hypothesis was beaten down when it became clear that the arms of a t rex could not reach its mouth. Yeah, this is one of those things that when we went to the museum in Chicago, the Field Museum, that became obvious. You can when you go up to the arm, Uh, the fossil bones of the t rex's arm, they are

the size of my arm. But the t rex is the size of like a two story house. And uh, clearly this is a shrunken limb exactly. But another hypothesis is that the baby arms were useful exactly for helping the t rex get back up when it was lying on the ground. So in the year nine seventy, the British paleontologist Barney Newman speculated that maybe the arms could help the t rex do a do a thing kind

of like a push up. It would be a push up motion where the where it would help the rex keep from sliding forward along the ground as it tried to raise its body to a standing position. Just imagine trying to rise without anything to brace you, like lie flat on your stomach and then try to push yourself up to standing using your legs alone. You might be

able to do it, but it's not easy. It's a lot easier if you can use your arms right, and it requires a fair amount of sort of coiling and slithering around for for most people, I think, And it's it's easier to imagine that kind of movement in our bodies as opposed to the t rex. Yes, so Ericson says, you know, now we know more about the biomechanics of the t rex than we did back when these ideas

were hypothesized. So of course, and I'm one. As we mentioned, the arms can't reach them out the mouth, so the meat hook theory that's dead. One thing we have learned is that t rex arms were often broken during life, as opposed to in an injury that immediately caused death. And this tells us some interesting things. First of all, it tells us that the arms were probably kind of bad at whatever the rexes were using them for. And

number two, they were not absolutely necessary for survival. The fact that we could have like examples of them having healed or not immediately killed the rex means that the rex could break an arm and survive for at least a month afterward. If an animal in the wild breaks a survival essential limb, that I mean that animal is generally pretty much done for, right, like a cheetah breaking a leg, etcetera. It's it's, it's done. And this suggests

four limbs that were not survival essential. Also, though the rex arms would have been strong by our standards, like he says they could probably curl four hundred pounds, they would not have had strong enough bone structure in the wrists to lift what he calls large mechanical loads, and that would include the rex's own body. So this means Newman's push up hypothesis is probably wrong, right, that the t rex did a push up in order to get up from the ground. So how did they get up

once they were lying down? Well Ericson suggests looking to birds who get up without the aid of four limbs, and apparently what they do is they simply tuck their legs directly underneath their center of gravity and then push straight up. Actually, probably sort of the exact same thing you would do if you tried to stand up from the ground without using your arms. You try to gather your legs under you and then push up right. Yeah, exactly.

But also therapod dinosaurs with tiny arms like the t rex would have had the aid of their tails to help gain additional leverage or bracing against the ground. So the way I'm imagining this I could be wrong, but it's the same way you would brace your hands against the ground in front of you while extending your legs to stand up. Imagine a t rex may being able to brace its tail against the ground behind it while pushing up with its legs, a sort of backwards standing.

You know, all of this, I think it goes It's just another reminder that the t Rex one of the most famous dinosaurs, if not the most famous dinosaur, that was the specimen out there, and also one that we we know a fair amount about there in a number of the fossils that have been found, and yet there are there's there's so much that we do not know

about the t Rex. There are things about it that we will we will never know unless we get that time machine to go back and start hunting them, or if we somehow bring them back to life with a Jurassic Park scenario. I propose a pre emptive ban on dinosaur hunting before we have any time machines. We've got to get the regulations in place. That's right, We've got to think ahead of our technology. Alright. Well, on that note, we're going to take a quick break and we'll be

right back. Thank alright, we're back, alright. So one of the big questions I had to in all of this is, alright, we we've looked at bipeds in prehistoric times, look at the bipedal world around us, uh that the humans have built. We're always trying to figure out what's going on or what could be going on in other worlds, What other kinds of life have evolved, are evolving, or will evolve in the future. So, assuming the entire universe isn't dead

other than us, which you know, might be right. So, um, what's the deal? Would we find legged creatures on other worlds? And if we did, would we find bipedal creatures? We can certainly imagine extraterrestrial life that doesn't depend on legged locomotion, but intelligent life, life capable of achieving technology along the same lines as the human model. You know, we've we've got into this a bit in the past, discussing the notion of say a hypothetical aquatic species and what sort

of technology they might be able to develop. Uh. As technico technology entails the mina manipulation of matter, one would need some sort of limbs of manipulation. Now, terrestrial nature provides us with other forms of manipulation beyond UH. You know, our hands, in our arms, they are the arms and tentacles of cephalopods. Uh, one could maybe turned to pseudopods and UH and other organisms so they're not used for

tool use. But if we're just imagining some sort of an organism manipulating things, I think pseudopods are on the table. I just had a crazy idea, what about a magnetic organism, like it's got like a skin surface that can manipulate things by changing magnetic attraction or yeah, or it's picked up. I mean there are animals in the natural world that utilize magnetism to a certain extent, right, so maybe there's

something there. Um. But when we try and think of tool users that engage in tool use, uh without engaging in pipedal movement, well, you know, a few varieties of of octopus come to mind. Uh. We can think of dolphins, and we of course do see a lot of bipedole use in apes and birds. But then we have these animals that engage in tool use via the mouthparts or in the case of elephants, with their trunks. You know Ian M. Banks, the sci Fia writer, he actually explored

this idea, uh in his excellent novel Surface Detail. There are these creatures called the the pav Pavoolians, and they are they're like an elephant like quadrupedal species, but they have a pair of trunks that they use for tool use. In computer interface in the front, now, I was looking around for for any writings on this subject, and I ran across UH this paper Some engineering considerations on the controversial issue of humanoids by Gean Carlo Guinta from the

Department of Mechanics and UH. This is UH from the Polytechnico Deterreno and this was collected in Cellular Origin, Life and Extreme Habitats and Astrobiology and UH. Guinta actually lays out much of what I said concerning UH possible mobility methods, UH and more in a very succinct way. He writes, quote, mobility of a living being is strictly linked with how it gets its food and energy. Autotrophic beings may not need any sort of mobility, while heterotrophic ones and particularly predators,

usually need to move to obtain food. Large animals either are supported on a solid surface, float in a fluid under the effect of hydrostatic forces, or fly using aerodynamic forces. Very small beings may use other supporting mechanisms like surface tension, molecular interactions, etcetera. Since it is likely that an intelligent being has a minimum size larger than allowing to to

use these mechanisms, they will not be considered. Other solutions like magnetic levitation or jets are conceivable, but are quite hypothetical and will not be considered and uh. He goes on to point out that most animals on solid surface surfaces do have legs, and the evolution on our planet at least is characterized by a gradual reduction in the number of legs. He continues quote in general, the large is the animal and the lower is the gravity of

the planet. The easier it is to remain an equilibrium on a small number of legs, in the sense that the response of the nervous system to avoid falling down maybe less quick. From this point of view, low gravity, uh simplifies all operations related to motion. They go on to point out that the speed is important, that speed of course, is important for survival and uh and it's

an important factor in natural selection. And we can see this reflected in our dinosaur examples, right, are prehistoric creature examples, because something like the t rex is running quickly to catch prey, as are its theropod um um uh kin. And then that earlier example, the kind of weird lizard herbivore that would have conceivably been running to escape from predator. It seems another example where so much in evolution ends

up having to do with speed. Like you know, when we talked about what called the ideas behind what caused the Cambrian explosion, you know, this is another big open question in UH, in paleon oology and in the history

of biology and evolution UH. And one of the ideas there is that maybe suddenly the introduction of predation into the food chain drove an explosion in body plan adaptation because suddenly things needed to protect themselves and move quickly in order to survive or in order to well sylvia,

in order to survive, to catch or evade predation. Indeed, so again to continues and says that all of this UH means there will be quote a strong incentive to shift from walking a sequel of static equilibrium positions to running, which includes positions in which static equilibrium is not guaranteed. Large animals, possibly with a smaller number of legs may have been an advantage, and bipeds are a very good configuration for beings having an adequate controlled system. This is interesting.

So he's pointing out how one of the features of running is that that, like you, you can be off balance while you're running, because it's the same way like a bicycle works. You know, a bicycle works because you're by maintaining speed, you could do this thing that you couldn't stay balanced to the lower speed. Yeah. And if you're the t rex, ideally that that that herbivore is going to break your fall and you're gonna do it

with mouth wide open. Right. So they also touch on the fact that that tool use and manipulation amounts to a shortcut and evolution uh quote objects that increase the potentialities of its body working like prostheses. Uh Why why slowly augment your body over the course of you know, long stretches of time when you can do something like

this within a lifetime be a tool use. So they conclude that such an alien, if if we're trying to imagine an alien emerging in another world, that it would need to have some sort of of locomotion and some sort of manipulation organs quote the ladder being best derived from locomotion organs like legs, the humanoid layout with two arms and two legs seems to be optimal. This is

an interesting point. Yeah, I would I would have maybe said, okay, uh, who knows how many legs an alien we encounter might have, but if it's moving around on the land, I think this is some pretty solid reasoning. There tends to be evolution toward fewer numbers of legs over time for to increase speed, and that this can free up other limbs for tool use, which seems to be an important part

of tool using intelligence. Like you, you wouldn't need tool using intelligence if you didn't have hands to use tools with, right, Yeah, it's it's it's an interesting paper. I'm sure there's some there's some astrobiologists and biologists that might evolutionary biologist that may take issue with this, but but I think I

think the author makes an interesting argument here. And it also as much as I love multi legged aliens in my sci fi, it also gives me a little support for visions of bipedal aliens being the dominant UH form

in so many different science fiction visions. Now, this also makes me question what unexamined assumptions are we bringing on void that could be clouding our vision Right here, we're we're thinking, Okay, I'm just trying to universalize about like the physics of planets and the principles of evolution and not be you know, Earth chauvinist. But but I bet there are ways that that we're somehow being Earth chauvinists that we're not noticing. Yeah, and I we haven't even

talked about tales. I can easily imagine some sort of an alien creature with a prehensile tail um or you know, some other prehensile uh that if they're an animate that they're able to use for tool use and manipulation. Well, to bring it back to the t rex is, I think we did mention this, but despite the fact that we don't have tales, tales often form an extremely important part of bipedal locomotion. The tails are there to counter

as a counterweight for the front of the body. If you've only got two legs and you're like a t rex, you're leading forward. You know, you saw these old pictures where people used to illustrate t rex is with their tail is dragging on the ground. That doesn't make any sense that they of course had to have their tails up in the air as a counterweight to the body

so they could move. Yeah. I am also reminded of kangaroos, who have you know, engage in bipedal gates and their tails is often utilized as a is a third limb. So yeah, there's a whole bunch that we could do there. I also have to say there's a whole episode we should probably record on just bipedal robots and the attempt to create functional bipedal robots, and perhaps getting into the idea of why we want to do it as well, because they've got to be like us, gotta be like us.

We got to create a mechanical man. So we'll will inevitably come back to that topic in a future episode, but for now, there you have it. Bipedalism something we do, something other organisms do, something organisms have been doing on this planet for a very long time, and conceivably there could be other bipeds out there in the universe doing their thing as well. Now, if you want to check out more episodes of Have to Blow Your Mind, head on over to stuff to Blow your Mind dot com.

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