Lucy and The Nutcracker - EWTS #003

Joe: Hello, welcome to Enough with the Science, I'm Joe.

Senan: And I'm Senan, and this is the podcast where we take some completely obscure and boring science topic and we make sure that you will never have any interest in it ever again.

Joe: Yes you will end up screaming 'enough with the science' before the end of this podcast, and we're making no bones about this week's topic.

Senan: Joe, that is the worst pun I've heard in a long time.

Joe: Nobody gave me that responsibility, you're making a mistake. Anyway, this week our topic is extinct human species, which is a little bit of a clickbaity title, unfortunately.

Senan: Now for anybody who's living in a cave, see what I did there, caves are also relevant to this week's topic, yes go on.

Joe: Clickbait, go on, what does clickbait mean?

Senan: You know those overly enthusiastic headlines that have certain buzzwords or buzz phrases in them that attract people's attention, they're just trying to get their eyeballs into, your eyeballs rather, into their news page because they have it plastered with adverts.

Joe: Essentially a lie, what you're saying is it's essentially not true.

Senan: Well to quote our Prime Minister who recently was accused of telling a lie in the Dáil, he said actually no it was an untruth, not a lie.

Joe: Yes, there is a very subtle difference.

Senan: I'm not quite sure what it is. Anyway, on with the show. The reason why it's a bit clickbaity is of course there's not really any extinct human species, we're talking about human-like species that are gone extinct.

Joe: So human-like, it's sort of like the way you feel after like a night out, the next morning, you're kind of not quite human but human-like.

Senan: No actually I think probably you feel a little bit too human the next morning.

Joe: Yes, possibly. So well I think we might need to define human-like in this context then.

Senan: Yeah, so we are talking about, as you probably know, our closest living other species are chimps and bonobos, you know they're...

Joe: You speak for yourself.

Senan: And we've analyzed, when I say we I mean scientists who know about these things, have analyzed the DNA of those creatures plus ours and they can see that there's an enormous amount of commonality, there's only like one or two percent of a difference. But they've also known from that analysis that there is a common ancestor that chimps, bonobos and ourselves all descended from a common ancestor who is now extinct. We don't know exactly what that common ancestor looked like, but these human-like species I'm talking about all also would have descended from that common ancestor that was common to chimps, bonobos and us.

Joe: So okay, so there's the three, there's the chimps and bonobos, poor old gorillas and stuff we're leaving them out, they're like kind of...

Senan: They're further out on the tree, they're not as closely related to us.

Joe: But they could still be human-like? No, they're not, they're away, different branch completely. And so then from this one species approximately sixteen or seventeen years ago...

Senan: Sixteen or seventeen years ago?

Joe: Yeah, like with this one, this overarching species, how long ago are we talking, are we talking...

Senan: Oh we are probably talking five to eight million years, something like that.

Joe: Okay, so a long time ago.

Senan: Sounds like an awfully long time. Do you remember the planet is like four billion years old, so that's four thousand million years old.

Joe: It's still a long time if you were, I don't know, waiting for a bus or...

Senan: Well if anecdotes in Dublin are true some people do indeed wait that length of time for a bus and then it doesn't come even though the sign says there should be one. Anyway I digress.

Joe: Yes, that's what we're here for, that's what we are here to digress.

Senan: So this week, our topic is extinct human species. For me I suppose one of the most mind-boggling aspects of all of this is the fact that, you know, there's actually about twenty of these species that have been discovered from fossils. I mean everybody's probably heard of Neanderthals and for a long time I would have assumed that was the only pre-human, you know, species that was around, but actually based on the fossils that have been found, there's about twenty of them, which is mind-boggling. Imagine if they were all still around, what the world would be like now.

Joe: Oh, I don't really want to imagine that.

Senan: Well considering the amount of bigotry and, you know, abuse we give other members of our own species who look a little bit different from us maybe because of skin color or whatever, I'd hate to think what would go on if there was all these other species around, you know.

Senan: Maybe that's an overly pessimistic view of the world.

Joe: Yes it is. Yes it is Senan.

Senan: But I guess we should probably talk about fossils and what they are.

Joe: Why?

Senan: Because fossils are how we know these things exist. If it wasn't for fossils we wouldn't know any of these things exist, or did exist once upon a time, none of them exist now as far as we know unless they're very good at hiding.

Joe: So before the fossils there was no idea, like so before the fossil hunters nobody knew that there were other species than us before us?

Senan: So one or two of the more recent ones, the more advanced ones we'll call them, have left things like art and jewelry and stuff behind, and tools and things. But probably it was assumed that was all human sourced, before we understood that some of these other creatures existed, you know.

Joe: Right. So I can imagine that the first person who discovered a new species of human-like creature probably met with some pushback.

Senan: I would think so yeah. I mean, you know, in times gone past obviously certain school of thought that was popular amongst the establishment was that, you know, humans were special, were, there was nothing else on the earth with the same prowess as humans and the same abilities and so on. So yeah, I mean it took an awful long time for scientific mainstream I think to accept that we are just evolved animals that we've evolved from the same stock as...

Joe: We're essentially really, really smart monkeys.

Senan: Well yeah, we are essentially monkeys who think they're smart.

Joe: Yes. I've taught myself smart.

Senan: So yeah, the fossils are basically, so I mean most creatures that die, they don't end up becoming fossils because, you know, their remains are scavenged.

Joe: Some animals that are alive are a bit fossils, fossil-like. Not looking at anybody in particular across the table.

Senan: I have no idea who you're speaking about because I don't own any mirrors. But yeah, so in order for something to become a fossil, they're rare enough because in order for something to become a fossil it has to be covered up with mud or silt or sand or something very quickly after it dies so that the remains lay undisturbed. And then later on that mud or silt or whatever, it's encased in has to become waterlogged, and what happens then is typically the softer parts of the creature do decompose but the harder parts like bones and teeth, the minerals that are in the water that's submerged in kind of gradually make their way into the bones and into the teeth and solidify them.

Joe: Into?

Senan: So you've got bones and teeth or whatever left over from the creature and then that's submerged in a mixture of mud and water and what have you. And that water contains minerals that it has leached out of rocks at some point in the past. And those minerals later on leach into the bones and teeth of the creature and kind of solidify them into the fossil.

Joe: And so the fossil is not bone anymore?

Senan: There would be some organic material in it, yeah. But generally speaking in order for it to survive down through millions of years it's got to be predominantly rock. But they have managed to extract bits of DNA from fossils so not all of the organic material is destroyed, you know.

Joe: And so will they be able to bring these back to life if they have them in the lab?

Senan: Well that was the Jurassic Park premise.

Joe: Don't destroy it for people. Don't destroy it for people.

Senan: Anything's possible. I mean we may reach a stage where we can actually create any DNA that we want, you know, we may, we think we can't really do it now, we can edit existing DNA but we can't wholesale create a brand new genome but it's probably not a million miles away that we might be able to do that at some point. Whether it's advisable or not is another matter.

Joe: Since when has that ever stopped us?

Senan: Indeed.

Joe: So, tell us about a few of these people.

Senan: Well, I suppose the first thing you've got to ask yourself when you realize there was twenty species is, you know, how come we're still around and they aren't, have we outlasted them all? And that's not entirely true. So we've been around, humans have been around for about three hundred thousand years. And some of these other creatures were around for over a million, in fact in the case of one particular species probably about a million and a half years. So some of them were around a lot longer than us and they appeared a lot earlier, like the earliest ones go back to about four million years ago. So, you know, they were around a lot sooner than we were. So it's not so much that we have outlasted them as, you know, we are in terms of the age of the earth we are a relatively young species, we're only three hundred thousand years old.

Joe: And how likely is it that we're going to make it to a million years? That's a long way away.

Senan: That's three times, more than three times our current age. Yeah you'd have to wonder, wouldn't you, with the development of powerful weaponry and God knows climate change and you name it.

Joe: But if these were, so if they were here for a million years, and we've been here for three hundred thousand years, and look at the damage we're doing to ourselves, so theoretically they should have come up with interesting technology stuff.

Senan: Yeah, I mean like, well we've only had anything you might call a civilization like cities or societies or whatever for less than ten thousand years. So we were around for an awful long time before we got did any of that stuff. But, you know, for the ones that are around for a million years you've got to think that there's at least a possibility that they came up with some kind of organized civilization, some kind of technology be it very rudimentary, you know, some kind of buildings.

Joe: Even language, you would imagine that they've got some form of...

Senan: Language, agriculture, fishing maybe, you know, that kind of stuff.

Joe: Playing the drums.

Senan: Playing drums, yeah.

Joe: I bet you they got that far.

Senan: But we have found no evidence of it, but that doesn't mean it didn't happen. I mean it was a long time ago so it could have happened, the evidence might just have disappeared over time.

Joe: Yeah. So a few of these characters.

Senan: Yeah. And we did, we did just to go back on something, I don't want to create the impression that they were all gone before we arrived. We humans did coexist with some of the later more advanced ones, which we'll talk about in a minute. But let's go back a little bit further. One of the most famous ones was called Lucy, she was found in Ethiopia. Her official Latin name Australopithecus afarensis.

Joe: I prefer Lucy.

Senan: And her species existed between three to four million years ago. So they lasted about a million years. Any idea how she got her name?

Joe: Because she wasn't tightly packed into a whatever she was, whatever sort of receptacle.

Senan: That would be L-O-O-S-E-Y.

Senan: No, she's L-U-C-Y and it's I'm afraid the simplest explanation.

Joe: She was juicy, Juicy Lucy? No.

Senan: I think somebody on the archaeology team was a big Beatles fan. So Lucy was in the sky.

Joe: Aha.

Senan: Anyway, the reason she's so famous is because they found about forty percent of a complete skeleton, which in fossil terms that's like a huge amount. Normally they find like one jaw bone or a hand or something. So to find like forty percent of a complete skeleton was a huge find. And as and since then they have found other examples of that species in other places.

Joe: And did they find Lucy, was Lucy like a skeleton like together that the rest had sort of disintegrated or was there was a bit of her over here and there was a bit of her over there or that kind of she was scattered round the place in some sort of ritualistic horrific...

Senan: Although I was a member of that archaeology team I was on a day off that particular day so...

Joe: I thought so. I thought so.

Senan: So like I you know who knows where exactly they found Lucy, but I'm sure our listeners there's a little bit of homework for our listeners now, fire up Chat GPT and ask it where was Lucy and was she all in one piece.

Joe: Yeah, maybe maybe want to be more specific than that.

Senan: (laughter) In fact that question could be asked about me after a night on the tiles.

Joe: Anyway, interesting thing about Lucy's people is they were one of the earliest examples that we know were able to walk on two legs. Now based on their bone structure looks more like a kind of a waddle instead of a walk, but they also could climb trees so they were a kind of a dual purpose body plan and that adaptability probably helped them to survive as long as they did because, you know, they could live in forests or they could live in places that required them to walk like out on the plains or whatever.

Senan: It is it's kind of a pity though isn't it that we humans have kind of lost our ability to tree climb.

Joe: It's kind of kids still do it.

Senan: The kids still do it yeah and everybody just goes stop, stop doing that, stop climbing trees.

Senan: And then when we become adults we become just more interested in social climbing, it's we lose that interest in tree climbing.

Joe: Speak for yourself again, social climbing. Right we're going to move on to somebody else. Another another interesting name I like the ones that have the weird names, they're probably the least interesting scientifically but the names are kind of notable. Next guy is Nutcracker Man from Tanzania. So Paranthropus boisei is the official name.

Joe: I think you should call him that, I think you should give him his official moniker whenever you refer to him from now on, Paranthropus boisei.

Senan: It's a pity the Beatles didn't somehow manage to come up with a chorus that that rhymed with.

Joe: Paranthropus boisei in the sky.

Senan: Anyway those guys also lasted about a million but they were more recent, about a million years. They were between one and two million years ago is when they existed. And the reason our friend got named Nutcracker Man is because they did ballet.

Joe: Did they really?

Senan: They were really good at ballet, they went straight from the trees to walking to ballet, they just jumped. They did consider Mikado Man briefly. No, he had he had pretty large tough teeth and huge jaw muscles. So they they kind of imagined that maybe he was cracking nuts with his teeth. I mean, you know, maybe when he went down to the pub on a Friday evening with his mates he liked an old bag of KP nuts you wouldn't know. But probably he was eating raw plants, roots, grasses, that kind of thing that required a lot of chewing. Now I have my own kind of theory, completely unfounded, no evidence about why Nutcracker Man and his people are have departed from from this earth. I say, you know, they had a relatively small brain, we know that from the fossil of the skull. So probably no challenge to Einstein really and I'd say once they realized they had teeth capable of chewing hard things they started chewing granite because it tasted a little bit spicy due to the, you know the radioactivity that's in granite. And of course no nutrition in granite so you know they died away in the end.

Joe: I would imagine their teeth wouldn't have lasted very long.

Senan: Yeah that didn't help either I'd say because it was going to be hard then to suck the grass. Right that's Nutcracker Man, we'll move on to Handy Man.

Joe: Okay.

Senan: Handy Man was one of the smarter ones. His brain was a bit bigger than Nutcracker Man and his official moniker is Homo habilis.

Joe: Yes. This the first well one of we've moved from Paranthropus boisei to Homo.

Senan: I'm impressed you remembered that.

Joe: Writing is a fantastic thing. Writing is amazing when you write down something you can read it. But okay so now we're on to Homos of which we have quite the collection.

Senan: Yeah obviously we're Homo sapiens and um there are about ten of these pre-human species that have the name Homo something or other. So that's they're closer related genetically closer to us in the evolutionary tree than the other guys I was speaking about earlier on. This guy Homo habilis, first use of simple tools. So the first creature we know that actually...

Joe: A leaf blower. It would have been very useful I I think like kind of on the plains to have a leaf blower, you would have been out your head like just even in attracting a mate I think if you saw a Homo habilis with a leaf blower you'd be like mmm I like the cut of his jib.

Senan: Yeah and you know that that wireless sander came in very handy when you were trying to smooth down the trunks of trees. No we're talking about like he might have picked up a nice oblong shaped stone and chipped it in half so that he'd have a sharp edge at one side of it. What they tend to call a fancy name a hand axe, just a stone with a bit of a sharp stone. That kind of thing, basic tools but still he at least I mean tool use is considered by scientists to be or was at least to be a an indicator of intelligence. There was a long time up until maybe forty or fifty years ago that we thought that humans were the only creatures that used tools. Now we know that lots of other creatures, chimpanzees, crows even use tools.

Joe: I realize this is depressing me like I'm just useless at using tools. Like just to a horrific level. Like I have there's I don't know how many drills I've bought and they're all still sitting there gathering dust.

Senan: But lucky for you there's dozens of crows on the roof of your house so just you just need to speak nice to them, they'll come down and they'll do all the tool work for you.

Joe: That's how we get done.

Senan: So yeah he first user of tools, he also kind of partially walked upright.

Joe: He sounded more and more like me.

Senan: Yeah yeah on Friday evening on the way home from the pub partially upright is about as close as I can get to it. So next one, we moving rapidly along. The next one Homo erectus, a really interesting bloke.

Joe: No jokes, we're not making any obvious jokes about this.

Senan: No we're going to we're going to leave the juvenile jokes outside the room. Anyway one particular example of Homo erectus was called Java Man. And he was called that because he liked a skinny latte first thing in the morning in the cave before he could...

Joe: That is such an obvious joke. That's such an obvious joke.

Senan: And and it's completely unrelated to the fact that he was actually found on the island of Java you know. Anyway this guy had an even bigger brain than Handy Man and more much more advanced tools. But also a lot of other interesting attributes that makes him more like a modern human. They used fire, first one known to use fire you know for cooking or heat or whatever. They were fairly sure they built boats because they traveled all over the world, they like a lot of these species most of them originated in Africa and these guys traveled and spread around the world and moved including several islands in Asia that they couldn't have got to without using boats. So this is a big species, a big jump forward. They walked fully upright unlike the previous guy who kind of might have been a bit stooped over. They also were the longest lasting that we know of these pre-human species, they were around for one we reckon about one and a half million years. So these these are real important guys and it's like only about a hundred thousand years ago that they went extinct so humanity, our ancestors human beings, would have known these guys.

Joe: So we're not directly descended from these dudes? We're sort of we existed...

Senan: Oh no I mean just to clarify what I'm describing here all these different species, I'm not saying that you know each one is the parent of another one that's the parent of another one. What we're saying is that all of these species arose from a common ancestor that we have with chimps and bonobos.

Joe: Okay so distant distant cousins.

Senan: We're not certain but some of them might be forbears of ours but they they could also be more regarded as siblings or cousins you know.

Joe: Next thing we come onto of course everybody's favorite pre and indeed famous pre human species and that of course is the Neanderthals. Homo neanderthalensis as they're known as officially.

Senan: We know probably the most about these ones such I suppose is why most people are aware of their existence because we have found so many fossils from these guys. Again they're a recent enough species so humanity would have known them, our early human beings would have known them. They've only been gone for about forty thousand years which is not very long ago at all.

Joe: And is that is that why there's so many fossils? Is that because the time?

Senan: Yeah probably, also they were fairly widely distributed, they were over a wide area. But also yeah the fossils do degrade so you know more recent species were more likely to find fossils than than older ones. But the interesting facts about them, they had bigger brains than us and may well have been smarter than us.

Joe: Doesn't surprise me.

Senan: Yeah so it's a bit of a mystery like they only went extinct forty thousand years ago, what happened to them? There's a dark theory that maybe we did them in.

Joe: I'd say you just didn't like the neighbors, they were just like look at these guys look at what these guys are up to.

Senan: Oh they liked the neighbors all right.

Joe: Oh really? Oh no this is like one of those Housewives of Beverly Hills or something is it? Neanderthals of Beverly Hills.

Senan: Because there are a certain number of humans, modern humans in the world today who have snippets of Neanderthal DNA.

Joe: I think I know a few of them. Am I allowed use real names? Maybe not.

Senan: Well I just don't know if we have the legal fees, we could be both bankrupted. But yeah clearly in the past some human beings were especially friendly with their hairy Neanderthal neighbors because they were they were sharing DNA.

Joe: But were like originally like three hundred thousand years ago would humans, Homo sapiens, be remarkably different than Neanderthals? Like would they be would they look like us now and the Neanderthals look kind of I don't know more like an orangutan?

Senan: Well the humans should have looked like us now you know minus the the tummy tuck and the Botox fillers and what have you.

Joe: Right so basically humans look like they were at a festival.

Senan: Like the Neanderthals their skull shape is a little different, I mean they they would be recognizable immediately as as not human.

Joe: Right so it's not like you were at a party and it was dark and you kind of made a mistake.

Senan: Well I'm sure there was a bit of that. Remember they didn't really have electricity or candles or anything like that so you know anything was possible in the long winter nights. Any port in a storm as they say. But yeah they were they were pretty sophisticated creatures like they had very very advanced tools you know proper axes with handles that they fashioned themselves and what have you. They made their own jewelry, they left behind art, there's Neanderthal cave paintings. They used fire for heating and cooking. So yeah it they're pretty advanced the Neanderthals. But the funny thing is this inter species shenanigans was not all that rare because there is another pre-human species called Denisovans who also have some of their DNA in modern humans. So there was there was obviously a bit of how's your father going on with them as well.

Joe: It was fun times back then. And the Denisovans were from how long ago are they?

Senan: They're pretty recent too, they would have been contemporaries of the Neanderthals. And we there hasn't been that many fossils of that crowd of the Denisovans found. It's such a recent find that they haven't even been given a proper Latin classification so they probably will end up being Homo denisova or something like that but right now they're just known as the Denisovans. So finally we come to the one species that actually makes the name of this episode the truth or more or less the truth.

Joe: What's the name of the episode again?

Senan: (laughter) Extinct human species. So in East Africa it's believed that a hundred and sixty thousand years ago there was a species of human only slightly different from us. Effectively a sub-species of our own species. And so they're called Homo sapiens idaltu. So you're talking about really minor differences there like they're almost exactly the same as modern humans just small differences in the nose and the back of the head, that kind of thing. Just tiny like small changes in the structure of the bones.

Joe: An extra arm.

Senan: It's enough that the differences are enough that they're outside the range of what you might call the normal range of differences in humans. But there's only they've only been discovered in a small area a couple one or two fossils so we don't know a lot about them or even how long they they were on earth for but one would assume they were around for a decent amount of time as well.

Joe: They could have been aliens. They could have been aliens, they could have just visited.

Senan: We might all be aliens.

Joe: Yes absolutely. I just want to throw it in there so we get another hour for Senan, off we go.

Senan: You've just you just mentioned a concept that is known as panspermia.

Joe: Oh god. You just wanted to get that word in there.

Senan: And it's the theory that the the building blocks of life might have come to earth on an asteroid that was driven off another planet. So the basic idea is that some large lump of rock flying around in space crashed into we'll say Mars or some other planet and it drove a lump of Martian rock, the impact drove a lump of Martian rock off the surface, living on that rock maybe was some Martian microbes and then it eventually flew through space for years and years and eventually landed on earth and seeded earth with life. There's no proof whatsoever, it's it's it's a theory about the possibility of life spreading from one planet to another.

Joe: So if you join us for episode thirty eight we might come back to this.

Senan: Panspermia yeah it's an interesting it's an interesting idea. So we should briefly talk about walking because walking of course is going to be very difficult sometimes.

Joe: Walking can be extremely difficult as some of our ancestors found out.

Senan: You might be tempted to assume that walking is something that arose hand in hand with intelligence. And there's a grain of truth to that but only a grain. By walking I mean walking on two legs. The so once we developed hands that could grip things and the intelligence to use tools with those hands it was of course convenient to be able to move around the place, walk around the place and still carry or use those tools. So that was that was kind of one of the things that made it a good idea for us to walk. But aside from that there was climate change going on about six million years ago. So before that period the earth was extensively covered in forest and so you were talking about monkey-like creatures using their four legs four arms and legs...

Joe: Eight. Six million years ago there's monkeys with eight arms and eight legs.

Senan: Anyway they used those to climb around the trees. They might occasionally come down on the ground and crawl around on all fours but they needed all four to crawl around the trees. Then the climate change happened and the forests started to shrink and grasslands, flat plains covered in very tall grass started spreading to replace the forests. And suddenly you needed to be able to see over the grass.

Joe: To wave at the neighbors.

Senan: To wave at the neighbors, see what the neighbors are up to. Make sure the neighbors are not coming to steal everything you have and and murder you and your family.

Joe: I don't want these neighbors.

Senan: You want to be able to see if predators are coming, you want to be able to see where your prey is, all of that stuff you need to be able to look over the grass.

Joe: Amazing though like because you would imagine that looking over the grass then the predators could see you too.

Senan: Yeah but I mean it's a two way street, if they can see you presumably you can see them and you run away. And that brings raises to an interesting point actually one of the one of the downsides of walking on two legs is that four legged creatures can sprint a lot faster than two legged ones can. So you know your average lion or tiger is is going to catch up with you pretty quick even a four legged saltwater crocodile like the ones they have in Australia can run faster than people. So it's we're talking about sprinting, I mean the the two legged crowd ourselves and any other creatures walking around two legs they're able to go long distances quite efficiently very efficient use of energy. So our our ancestors out on the plains they were kind of hunter gatherers who might have walked thirty kilometers in a day every day and that was no problem, it was very energy efficient to do that.

Joe: Wow. Should we be doing that? Should we be doing that? Would that be good for us now?

Senan: It's interesting you know this ten thousand steps thing that some of the some of the step counter watches have, that that started as a marketing wheeze by one of the watch companies there was wasn't based in science at all. But some scientists anyway decided to test out the theory and they found amazing coincidence sure enough ten thousand steps was kind of the magic number that doing say fifteen thousand versus ten thousand in a day there wasn't much additional health benefits but doing less than ten thousand there was fewer health benefits than doing ten thousand so it's interesting that something that started out as some marketing guys wheeze actually turned out to be true.

Joe: Somebody guessed the right answer. That's all it is, somebody guessed the right answer.

Senan: Yeah yeah. So should we be attempting I imagine so ten thousand steps right great, fifteen thousand steps not much of a difference. But if you're doing thirty K that's a bit more. That's slightly more than ten thousand steps so like would thirty K be good for us as hunter gatherers of old. Well the the wear and tear on our joints and on our back and stuff probably wouldn't have become apparent until we were over normal childbearing age.

Joe: Childbearing, where did that come into it?

Senan: Well it we're talking about evolutionary pressure here right. So after you're gone past the age where you're normally having children evolution doesn't care about you. So if you're back...

Joe: That is a terrible thing to say. And also very depressing.

Senan: Evolution is quite happy to see you die out in a ditch if the environment if you can't adapt to the environment.

Joe: Would you hit like fifty or...

Senan: You're not doing any good. So so you know if if your hips and your knees and your back all can put up with walking on two legs thirty kilometers a day until such time as you've delivered children into the world evolution is perfectly happy. You can you can then fall over for all it cares. So it doesn't it doesn't bode well for like are we living too long is what you're saying then as far as in evolutionary terms. Some people probably shouldn't have lived longer than a few days but we're stuck with them. But anyway like my my I had some back trouble myself and my doctor my back doctor had a a funny turn of phrase I asked him why the hell was he so busy with so many patients and he said well he said God gave us a clothesline and we are using it as a flag pole.

Joe: So I think you're going to need to explain that.

Senan: So his point was that our our back bone our vertebrae and our back bone evolved when we were walking on all four legs so it was normally horizontal to the ground and the weight of our body was hanging off it horizontally. But now since we started walking on two legs we've it's now vertical, we hold it vertical and all the weight goes down through it from from you know so it's putting pressure on the bones putting pressure on the discs that are in between the bones and so on. So although we have evolved a lot of adaptations to allow us walk properly on two legs walk efficiently on two legs our back design still needs to evolve a bit further to cope with with that and as do our hips and our knees and things.

Joe: But evolution has absolutely no desire to help us do that.

Senan: No none whatsoever no.

Joe: So the likelihood of it happening is...

Senan: No. We will just have to rely on a robo skeleton being applied.

Joe: Robo skeletons, I like where this is going.

Senan: So yeah so that's all about pre-human species and the the wonderful world of things that were alive once upon a time but are no longer around.

Joe: And now we've come to a then just before we finish we've come to a new section I'm going to surprise Senan with called Limerick of the Day. So whatever our topic is we have to try and write a limerick about.

Senan: That'd be a good name for a movie actually, The Day of the Limerick. I can imagine it being a Marvel blockbuster.

Joe: Or a really really a black and white kind of artsy kind of film with like children running down barefoot streets while people read limericks.

Senan: Barefoot streets I have yet to see a street wearing a pair of shoes.

Joe: So the winner in our prize for our Limerick of the Day was there once was a Homo Erectus who prepared a detailed prospectus. He told all his peers that in one million years scientists may dig us up and inspect us. And I think that brings us to the end.

Senan: That deserves a round of applause.

Joe: So that brings us to the end of this episode of Enough with the Science, I'm Joe.

Senan: And it's enough with the Joe, I'm Senan.

Joe: Okay thanks for listening, hope you'll join us next time.