Before We Were The Last Human Species: When We Lived With Neanderthals

SPEAKER_00 0:00 Imagine a world where Neanderthals, Denisovans, and Hobbits walked alongside us. For many thousands of years, this world was a reality. So what was it like to share the planet with all these other humans? And would we have recognized them as different?

SPEAKER_01 0:16 If you put someone into like Neanderthal like makeup and then dress them in a suit and stick them on the London Underground.

SPEAKER_00 0:22 They don't leap out. This is what we did before. I'm Ollie, and that is Mike Marshall, the go-to man, when it comes to ancient human species.

SPEAKER_01 0:31 It's entirely possible to me that they could have just changed their behaviour in so in some key way and the whole of the last 50,000 years would look very different and the planet would look very different now.

SPEAKER_00 0:43 From Homo erectus to Homo Naledi, today we're finding out what it was like before we were the last humans left on Earth. Enjoy. Mike Marshall, welcome to what we did before. It's a pleasure having you on. Great to be here. Thanks for having me. So what what ancient human species do we currently know about? And how certain are we about where one species of human ends and another begins? Like, is it is it a bit kind of blurry? It's it is it is blurry, yeah.

SPEAKER_01 1:13 So we know about a few dozen species. Um, and that sort of spans from seven million years ago up until like really quite recently. So you know the the last species that we know of that that went extinct seems to have been the Neanderthals about 40,000 years ago. So yeah, from 7 million to 40,000 years, there's this sort of huge history of uh other humans or hominins, as they're sort of technically called. And the exact number is uncertain, undebated, part exactly because the the boundaries between these species are kind of blurry. And there are just these endless debates about, you know, sort of are these two things that we've given separate names to, are they actually just the same thing? Or is this one this thing that we've previously thought of as one thing, should we actually split it into two or into three? There are about three sort of really early ones that are sort of moderately close to sort of be to being apes, and then there's a sort of human slash ape middle ground that exists for a couple of million years, and then there's the members of our genus, which is called Homo, who are much more human-like in terms of their sort of build. You know, they've got sort of largish brains compared to the earlier ones, they've got you know short, proportionally shorter arms and longer legs, sort of you know, adaptations for walking on you know, walking on two feet all the time. And there are fair few members of Homo. Some people might possibly get it down to as little as 10 or just under that, and other people would sort of drive it up past that. It's it's woolly. Part of the reason for that, and for the uncertainty is just that a lot of the fossils that we have of these hominins are just partial. Sometimes we yeah, there are a few cases where we've got like really complete skeletons. And in other cases, you it's literally like a skull and a few other bits and bobs, and you're kind of like, well, okay, what do you what can we sort of really make of that? And the the thing to always remember is that you know species are variable, right? You know, if you look at a population, two individuals do not look exactly alike. So how different do things have to look in order for you to confidently say, oh yeah, these these are definitely like separate species that we're not interbreeding with each other, uh, and these two are some sufficiently similar, we uh we're confident they're the same kind of thing. It's not obvious. It's just not obvious because you know every species varies, you know, they vary in size, um, and there there can be all kinds of like weird and wonderful alterations to like the exact design of the skeleton, some of which is just shaped by life experience. You know, if you um meet a modern human who has trained as a ballet dancer from a very young age, their skeleton looks different to mine, uh, because I did not train as a ballet dancer from a very young age. Um I know what gave it away. And you know, so they look they will look meaningfully different. And I think you know, if you were to sort of dig those skeletons up with no context and no none of that understanding, you might be tempted to think, oh, well, you know, are they are they something different? You know, what's what is this graceile, agile, nimble, nimble creature? Um, and I but it's it's because their bodies have been shaped by an experience, by a childhood experience that most of the rest of us didn't have.

SPEAKER_00 4:22 Yeah, I do I've always wondered this whether it be you know that it would be mad one day we realize we've been digging up all these bones, assuming there's uh the Neanderthals, the Denisovans, uh you know, Homo Naledi, and oh actually, they're just all Homo sapiens, they're just all different people.

SPEAKER_01 4:39 And I and I think that that sort of like that extreme version is probably not true. Um, and there's good and in some cases there's good reason to think that's not true. So in the case of the Neanderthals, we have DNA from them, and the DNA does look meaningfully different, but that's because we've got we happen to have that genetic data. Um, and in a lot of other cases we don't have that, and so we're you know we're left with these fragmentary fossils, and so we can be less comfortable.

SPEAKER_00 5:04 And some of the ones that people uh will know the best, you've named the Neanderthals, we've got the Denisovans, we've got Homo florensis, Homo Naledi, Homo erectus, Homo heidelbergensis. I I just wonder how many different homo species were alive on the earth at the same time, potentially interacting or potentially crossing paths or just sharing the earth without even knowing it.

SPEAKER_01 5:27 I mean, there's definitely a lot of overlap in time. Um, so one of the sort of really spectacular examples is Homo erectus, which the earliest known examples of that are from Africa from two million years ago. There's one from Ethiopia and one from South Africa. So that's immediate, yeah, immediately uh very widely separated places. But then within a couple of hundred thousand years, they turn up in Georgia, I mean Eastern European Georgia, not Georgia in the United States. And then a while after that, they show up in what's now China, and then eventually in Indonesia. The ones that are in Indonesia indu are there until a little over a hundred thousand years ago, so almost a two million year span. And in that, yeah, that's the period when you know Neanderthals appear, it's the period when Denise ones appear, it's the period when our species appears. Homo hydrobogensis has its sort of brief heyday in Europe. There's reason to think that the hobbits are sort of present on flores in Indonesia sort of towards the end of that period. Yeah, so clearly these groups are overlapping in time, and then the sort of harder question is do they also overlap in space? Do they actually meet each other? And sometimes we can be confident about that, and sometimes we can't. So, for example, there are there are some fossil sites where you can literally see um two sets of fossil footprints sort of walking over each other on the same like lake shore, and one of them looks like it's a Homo erectus, and another one looks like it's a different species, for example. So you can say, Oh, okay, okay, fine. So they're literally living in the same place and they're living close enough together that they're leaving footprints on the same um lake shore. And of course, with some of the species like ours and the Neanderthals, we can be confident that they met because there's genetic traces of that, because we didn't just meet the Neanderthals. Uh, some of our ancestors uh had sex with Neanderthals, and as a result, a great many humans today carry a certain amount of Neanderthal DNA. So basically anyone whose ancestry is mainly outside of Africa will have Neanderthal DNA. So I I don't I haven't had my genome sequence, but I'm confident that if I did, there'd be about 2% of Neanderthal DNA in there as a result of that period of interbreeding. So clearly uh modern humans and Neanderthals met because there's no other way that that was going to happen.

SPEAKER_00 7:48 And Denisovans too, the same story.

SPEAKER_01 7:50 And Denisovans too, yeah. So there's uh a great many people in sort of Southeastern Asia and particularly in like island Southeast Asia, places like Indonesia and sort of going further east to Papua New Guinea, where people have, again, a few percent of their genome is inherited from Denisovans. We can sort of know rather less about that in some respects because the Denisovans are the sort of sort of this very mysterious group that were discovered from ancient DNA rather than from like substantial fossils. You know, the the first evidence of them is just from like a little tiny little sliver of fingerbone, which someone managed to read the DNA from. But and it's taken 15 years to have even a partial skeleton of them. But yeah, so at least two episodes of interbreeding there. And then we also know that Neanderthals and Denisophans themselves interbred, just to sort of confuse it further, because there's a a specimen from Denisova Cave in Siberia, which is the place that the Dinesophans were first identified, where there is a sit there is a single fossil which has which is a first generation hybrid. I can never remember which one is the mother and which one's the father, but one Neanderthal parent, one Denisovan parent, literally, yeah, and this is this is a 50 this individual was a 50-50 hybrid. The fact that we can find that is kind of astonishing, really, because it's one thing to sort of find evidence of this interbreeding sort of tens of thousands of years after the fact, it's another to actually find an individual who is literally the product of that uh of that mating. And that sort of suggests that probably there was given how incomplete the fossil record is, uh, the fact that that fossil has turned up at all is kind of telling. I think that probably there was a fair bit of meeting and mixing going on because otherwise you just wouldn't find there wouldn't be that many of examples of hybrids, and the odds that one would actually be fossilized would be ridiculous.

SPEAKER_00 9:35 Yeah, what we've been able to discover about ancient humans in just the past few decades compared to what we knew about them through most of Homo sapien history, it's quite amazing just how far we've come. Like you can only imagine the knowledge that we're gonna glean five, ten years into the future, right? Oh yeah.

SPEAKER_01 9:53 I mean the the speed of the discoveries, particularly over the last sort of 30 years, has been quite dizzying. You know, I I worked it out a few years ago that we were sort of aver we were averaging a new species about once every three years. Wow. Yeah, some of these are finds are just like sort of almost filling in odd little corners of the story, but then others have been really dramatic. So up until the the tail end of the 90s, we really only had fossils going back about four and a half million years. There was nothing older than that. And then in the very early 2000s, like 2000 to 2002, there were these big finds of like a six million-year-old species and a seven million-year-old species, which just enormously extends the story. It's sort of easy to get sort of glazed by numbers. But when you sort of, yeah, okay, well, we we were back to about four and a half million, now we're back to seven, so we've but that's that's about half as long again.

unknown 10:49 Right.

SPEAKER_01 10:50 Um just at a stroke, uh, because of this, yeah, the discovery of Sahel anthropus in in Chad. So that's a that means that the story is longer. It means that we we sort of have to push back way further into time in order to um figure out what you know where we're coming from. It means that yeah, the instead of looking for the last common ancestors that we share with chimps, sort of you know, in five million-year-old rocks, for example, you know, okay, you've got to go back probably seven or more uh in order to find that um that ancestor which which still hasn't turned which still hasn't turned up, pesky thing.

SPEAKER_00 11:25 Yeah, and and actually um I think these big numbers, you mentioned this sort of two million year span of of other homo species um as well, it kind of paints this picture. I think we often think of ourselves as humans as sort of like the winners, the ones who are like, you know, we we beat all of the other ones and we sort of wipe them out, and here we are uh 300,000 years later, still standing. But we are not the most long-lived human species, you know.

SPEAKER_01 11:50 No, not but no, not by a long shot. I mean, if we if you assume if you assume that the sort of estimate of our age of about 300,000 years or so is correct, then we are way short of that. Yeah, Homer erectus was around for longer. Most of the Australopithecus species, which are the more sort of somewhat ape-like ones that were around before, seem to have kicked around for you know many hundreds of thousands of years, some possibly over a million. Some of the early ones, there's an earlier group called Ardipithecus. We only really have two decent sets of fossils of that, but one's 4.4 million, one's 5.6. So it's immediately over it's that group went went for over a million years. I also sort of never really I don't much like the idea that we like beat the other human species, because there's really little or no evidence of that. We know from genetics that you know our species sort of expanded out of Africa about 60,000 years ago, something like that, and quite rapidly spread to all the other to all these other continents. Go into Eurasia. Some people end up all the way into um Australia, perhaps by 60,000 years ago. It seems to take a bit longer to get into Europe, uh maybe by 45, and then there's this much later expansion into the Americas, which is a really hard thing to do, because you have to basically go all the way into the far northeast corner of Asia, into like the really chilly, hostile bit of Siberia, cross the Bering Strait into what's now Alaska, and then sort of come down from there. So that that took a that took a bit longer, but quite understandably so. Because you sort of see that quite rapid expansion again, set against this sort of seven million year story. That is you know, that is fast, there's no two ways about it, and it's really tempting to read it as aggressive, but I do think that that is sort of us projecting some of our own ideas onto the past. There's no particular evidence of violence. Um, you know, you might imagine, for example, that um you know when modern humans arrive in Europe and they and they meet in the Anderthyl, so maybe we'd find like evidence of greater levels of violence. Maybe we'd find lots of Neanderthal bones where like you know the skulls have been smashed in and there's like stab marks on the ribs or whatever. No, not really. There's yeah, there is evidence of violence, but it doesn't particularly there's nothing that sort of leaps out as like, oh, suddenly something drastic is happening here. There's just no there's no particular sign of it at all. Um they seem to coexist for several thousand years. And it's sort of tempt when you say the word coexist, that seems that sounds nice as well. And again, you know it's it's sort of tempting to sort of read that, oh well, you know, they're living alongside each other for several thousand years, must have been peaceful. Um again, I think that's just sort of projecting back things that we don't quite know.

SPEAKER_00 14:36 We don't know. Do you think um it's likely I mean the populations would have been much smaller? So the ones that were coexisting, you know, obviously some bumped into each other, some populations would have just never crossed paths. Do you think they would have recognized these other human species, say they came across a Denisov and Neanderthal as like one of their own, as like them, or would they not know that there was a difference? Or you know, I I I know that's really hard, that's kind of conjecture here, but I think I think it I think it probably depends on who they met.

SPEAKER_01 15:12 So, for example, it's distinctly possible that our that modern humans met Homo Floresiansis, the the hobbits uh on the island of Flores in Indonesia. I think they must have realized that there was something different about the hobbits because the hobbits are only a meter tall. Uh, and obviously modern humans, while while they're not as like tall as the average population as the average people now, you know, they're still mean well over a metre. Uh so I think they would have sort of recognized the the hobbits as being in some way smaller and different to them. Neanderthals do sort of look subtly different to us, like they have um bigger and heavier brow ridges above their eyes. There's a few other differences, they seem to have like wider noses, slightly sort of bulkier frames than than than modern humans from the same time period. But it is quite subtle. And there have been some sort of fun experiments done more recently where people have like if you put someone into like Neanderthal like makeup, but you but you get but you know, you give them a haircut, you know you you sort of do the sort of face-shaped stuff, but you don't sort of put them into like you know, matted looking prehistoric hair and then dress them in a suit and stick them on the London Underground, they don't particularly leap out. Yeah, I think it sort of depends on how attuned you are to that kind of difference. You know, Denisovans, we kind of know less about them because we have just so little fossil evidence, but they mean they do see they do seem to have been big guys, like but people have described them to me as like American football player build, uh, and with like correspondingly quite big teeth. Can easily imagine a Homo sapiens meeting a Denisovan thinking, oh he's a he's a bit in the way.

SPEAKER_00 16:53 Yeah.

unknown 16:54 Yeah.

SPEAKER_01 16:55 But I don't but I don't but whether or not they would necessarily think, wow, like radically different from me in this in the way that you know a chimpanzee or a pig or something is radically different from me. I think is it's a question of both like perceptual ability and just how much variation you expect to see.

SPEAKER_00 17:12 Yeah, and what they're really looking out for, because you know, we're digging up fossils and running DNA tests and things like that. This just wasn't on their radar. So and they were interbreeding, so that gives you maybe some idea that they thought that they were at least fairly alike.

SPEAKER_01 17:28 Yeah, I mean that they clearly can't at least some people can't have seen the two as being radically different because you just wouldn't be willing to uh mate with something that you really don't think is you. There's enough interbreeding that's happened, you know, in multiple occasions in multiple places over sometimes over sort of several thousand years. Yeah, the the the peak of human Neanderthal interbreeding seems to go on for about 7,000 years. That doesn't mean that like everyone is doing it, but it does sort of seem to suggest that it does it's not like a a wildly ridiculous and rare thing that hardly anyone is ever going to try. It's it seems to have been relatively commonplace.

SPEAKER_00 18:05 Aaron Ross Powell So we're we're saying uh really uh Homo sapiens came into contact with about three other human species. That's probably the most important I mean, at least I think it's distinctly possible that they met some more. I love this idea of this earth populated with different humans all coming into contact with one another, that's sharing ecosystems.

SPEAKER_01 18:26 I mean I s I sometimes wonder if like all the a lot of our sort of fantasy novels where we sort of are constantly imagining like elves hiding away in the forests and all this sort of thing, uh sort of actually tapping into something that is basically part of our that was basically part of our ancestors' experience.

SPEAKER_00 18:40 I thought this a lot too, actually, yeah. And the hobbits even um and and dwarves and uh all these sort of uh races that come in fantasy in fiction. Yeah, you can imagine this.

SPEAKER_01 18:50 And you can trace this stuff back through folklore, you know, it's it's it's very common. No matter where you go in the world, it's quite easy to find myths and stories about like the other people who are who might be sort of smaller or different in some way, and who you who are maybe sort of perceived as like kind of wise and beautiful and wonderful, or maybe perceived as malign, or maybe tricks. All these kind of different weightings get put on them, but it's really common to tell these kinds of stories. And certainly, if you imagine you know, Homo sapiens arising in Africa, you know, Homo naledias around in South Africa at the same time. There isn't fossil evidence of Homo erectus in Africa that late, we're constantly up against the whole is absence of evidence also evidence of absence, um, and particularly in the case of Africa, which is a huge continent that's fairly underexplored compared, certainly compared to Europe. I would not be surprised if actually there were some erectus pattering around uh later than the fossil record would currently suggest that they are that they were. Our sort of knowledge of like the ranges of all of these species is very tentative a lot of the time. Not all not always, I think the the range of Neanderthals is fairly well understood because Europe has been so thoroughly excavated and there are so many Neanderthal sites. There really is a sort of fairly good picture of where and when they were living. Which not to say that we won't like expand it at some point, but I don't think it's going to change too drastically for what it is now. Whereas for a lot of the other species, it really is sort of still kind of hazy. You know, one or two discoveries could radically change what we think they were doing or where we think they were living and when.

SPEAKER_00 21:37 I'd love to be launched back in time to explore the world like that. Um and I do you mentioned at the uh sort of outset we have shaped the planet in unfathomable ways, you know, completely reshaped ecosystems. And there's no evidence at all that other ancient humans had this sort of inclination then.

SPEAKER_01 21:56 Well, no, I think that there actually is, but it's just on a different, it's got a it's on a lesser degree and it's in different ways. We don't see them making like huge mega structures like building bridges across like mile-wide rivers, that kind of thing. But the oldest evidence of buildings, for example, is about half a million years old from uh Colombo Falls in Africa. And there are bait where there is just incredibly good preservation of wood, which mostly mostly is a thing that gets rotted away. But there are essentially wooden beams that seem to kind of interlock or fit together as if someone was building well, a building of some kind. We have no idea what what they were using it for, but they do seem to have built something. A lot of the sort of um things like stone circles and other megaliths, most of those are associated with our species, but there are a few exceptions. So there's a cave in France called Bruniquel Cave where there is a stone circle underground in the cave, and it's about 170,000. Years old. So it's way too early for our species to have been there. So with the implication being that Neanderthals made it. Now it's not as big as Stonehenge. We're not talking about like sort of huge towering megaliths. It's sort of it is sort of relatively modest, but still they were transforming, uh transforming the you know this place where they either lived or at least spent a significant amount of time. There's evidence from one place in Germany of Neanderthals apparently having uh cleared an area of forest. Again, nobody's quite sure what for. Like maybe there's a sort of speculation that maybe it made it easier to hunt, you know, if you just have like an open space where you can that you can chase the animals into and they can't hide behind trees. There's evidence, for example, of things like fire use going way, way back. So the the the sort of earliest good evidence of people of hominins using fire is about one and a half million years ago, so well before our species. And to some extent, it yeah, if if all you're doing is having like a little sort of cooking fire, then that's probably not maybe that's not transforming your environment in a in a large-scale way, although it might certainly might be transforming the food that you're cooking. But they may have been some of them may have been using fire to again to clear, to clear forest or to clear to clear vegetation out of the way so that they could. Yeah, it would be very difficult to sort of definitively show that because that would probably just look like a normal wildfire. Wildfires happen all the time. But yeah, some degree of control of fire goes back hundreds of thousands of well over a million years. Uh so it's not important, it's it's I think distinctly within the realm of possibility that some of these other hominins were using fire in that kind of way as well as in the sort of small scale way. And then the last thing I would just mention is um extinctions. There's this sort of long tale of extinctions going back over the last few sort of tens of thousands of years. And a chunk, again, a chunk of this gets attributed to our species because we turn up in certain places and things start to and things start to go away. But the other thing, it's quite likely that you know hominins were sort of driving down the populations of other species by hunting by hunting them, uh particularly as they sort of became more sort of skilled and capable at that. That will have changed the ecosystems in which they lived. You know, if you if you sort of start take if you start sort of chipping away at the population of big herbivores, that in turn has all kinds of knock-on, of knock-on effects.

SPEAKER_00 25:34 But maybe just in still slightly more balanced of a way than how we're changing ecosystems now. Yeah.

SPEAKER_01 25:41 Although I'm always sort of hesitant to sort of there's this whole there's this idea called the noble savage of like the idea that uh people who live in quote-unquote primitive societies are sort of in like in in balance with nature and living in harmony with nature, and they have this sort of deep wisdom. And I don't want it's really easy to sort of for to like be sort of unpleasantly prejudiced in either direction in this, on this, because you you can either it's it's obviously horrible to describe people from indigenous groups, for example, as being you know, stupid and primitive and savage, and all of these sort of horrible libels that have been hurled at these people. And it's kind of equal, it's almost equally bad and reductive to sort of describe them as being as you know living in harmony with with nature. Because it certainly if you're going back deep into pre-history, there are all sorts of concepts that people may have not understood yet. Like if you're if the if the population of a of a species that you're sort of hunting is declining really, really slowly, you may not actually realize that it's happening. Because if it if it plays out over a hundred thousand years or or or longer than that, your oral traditions are going to have to be spectacularly good in order to actually capture that, unless you're actually genuinely doing unless you're systematically collecting the data. Like it was hard enough for us as a species to notice that the the average temperature of the earth was going up, or to notice that many populations of wild animals are declining. It is difficult to find that out, you know, particularly if they if they're prone to hide or run away. Uh it's not it's not easy to count them. There has been a history in sort of anthropology and paleoanthropology of sort of treating ancient human groups as if they were sometimes unbelievably stupid and kind of being astonished when they do anything vaguely clever at all. And equally, I think it it's sort of it's sometimes tempting, particularly when we're sort of going through hard times at the moment, as we all very much are, to sort of romanticize these pastimes and sort of imagine it as being this kind of Edenic thing. And it probably wasn't that either. It was people being people, yeah. And just with less and having good days and bad days, and probably some of them were very nice, and some of them were absolutely terrible. Uh and some of them were just about that sort of vaguely grey thing in the middle.

SPEAKER_00 28:02 I wonder, um, talking about their lives, do we have any clues about what daily life did look like for them, though, for these different humans? Like, did did they make art and ornaments? Did they make music? Did they do did they have hobbies?

SPEAKER_01 28:18 The main thing that I would say about what daily life was like was that it was probably very different a lot of the time. Like it the seasons will have been much more important, at least depending on where you were. If you actually if you live in the in the tropics, maybe not so much because the seasons are much weaker in the tropics. You don't have but as soon as you start to wander out of that, then things like spring and winter become really important uh and and really sort of shape what you're doing. There's a sort of endless um argument about what gender roles were like, for example. So there's that there is this stereotype that the the men went out and did the hunting of like big dangerous animals, and the women did a lot of the gathering of you know, sort of vegetable matter type food. And that seems to be, at the very least, a very bad stereotype. So there's all sorts of evidence now that women did hunt and could be just as just as skilled as the men and just as useful as so if we it's it is true that sort of male bodies tend to be um slightly bigger and uh somewhat stronger on average, but there is a tool called the atalatle which allows you to sort of throw a spear. And if a a woman uses the atalatle to throw a spear, then she can throw it with just as much force and speed as a man can. And an actalatle is not that difficult a thing to make. Art is a complicated one because it's sort of there's all sorts of evidence for prehistoric art in the last say 50,000 years or so, and then it gets gradually sketchier. Some of that is going to be to do with preservation issues, particularly if you're if you're sort of painting on um rock, it can just it can be washed away, rubbed away. The oldest thing that sort of looks like it might be some kind of art is about a half a million years old, and it's a shell from Indonesia which has a sort of zigzag engraving on it, which looks like someone has scratched something into it. Given the eight given it's half a million years ago and given it's from Indonesia, the sort of assumption is that that's a Homer erectus doing that. You can then get you can then tie yourself into all these knots as to like whether or not this is really art, or are they just sort of just mucking about? And then you sort of say, well, isn't that just what art is to some extent? Does it it doesn't have to necessarily be this formalized thing? You know, if you draw a doodle or if you sort of just draw a doodle on a beach using a stick, it's art, isn't it? It might be rubbish art, but it's art. It sounds like what my two-year-old does, and I still class that as art.

SPEAKER_00 30:46 Yeah.

SPEAKER_01 30:46 Well, this is well, this is the other thing is that there's a whenever we sort of find an artifact from prehistoric times and we're not quite sure how to re how to interpret it, if it doesn't have like an obvious practical use, like sort of cutting things or whatever, then it's really tempting to sort of attribute to sort of say, oh, ritual then. Yeah. It's got some sort of like deep symbolic significance. Um could just be toys. Like humans are really unusual. One of the ways that humans are really unusual is that we have very long childhoods. Uh so if you live to the age of about 80 today, which is relatively common, uh, you will spend a quarter of your life as a juvenile. Like your body, I mean it it's really difficult to sort of actually draw a hard line as to exactly when you become an adult anyway. Yeah, you you might become um I'll get there eventually. Same, same. Yeah, you might but you know, you you but you might become sexually mature at the age of 13 or 14, but then your brain doesn't actually sort of finish developing until you're into your twenties. Where is the line? It's it's a it's a blurry line. But compared to other apes and even earlier sort of other hominins, our childhood is long. That means that in any prehistoric population there are a lot of children, and they're probably having uh a huge impact on what's you know, what's being made and what's being done.

SPEAKER_00 32:08 Yeah.

SPEAKER_01 32:09 I can't remember where this is from. I think it's from a cave in Italy, but there's evidence of basically like a prehistoric family day out where there's just like a bunch of footprints. There's a couple, there's a couple of adults, and there's three, I think three children of varying ages, and they just seem to have like gone into the cave with like burning torches and like done some painting on the walls and just generally mucked around, played in the mud. Well, I I spoke to the one of the researchers who had sort of studied this and she she said to me, Look, I'm probably reading too much into this, but I just kind of imagined that it was a rainy day and they didn't want to go out and so just like let's just let's just muck around in the cave, let's just take some torches and go and muck around in the cave, keep the kids out of mischief.

SPEAKER_00 32:45 Yeah, I wonder if that's a bit of a Homo sapien um desire is to say, because we have ritual and spirituality and religion, that all other homo species must have had that and they must have felt that same way. It is it possible? I mean, I don't know how clear the evidence is, but is it possible that none they simply weren't concerned with um with religion in that way?

SPEAKER_01 33:06 I think if we're if we're talking about homo, like our group, I find I find it hard to believe that there wasn't at least some thinking about that and some sort of concern with that. A lot of this just sort of stems from awareness of death. And awareness of death doesn't seem to be unique to humans. You know, there's evidence of you know you can of like all kinds of different wild animals grieving you. You there's like all this astonishing footage of elephants sort of gathering around like a fallen member of the group and just falling really silent and standing around very quietly doing nothing, and you you can't look at that without just getting a shiver down your smile. Like, they they on some level get this. They may not like understand it on the same intricate way that we do, but on some level they seem to understand that there was this this was like one of the group, and they had like a personality and traits, and we kind of knew them, and now they've stopped. And that you can find that in all kinds of other, like basically so highly social animals, you know, dolphins seem to have a sense of it, uh, even like some kinds of pigs, I think. So I find it hard to imagine that um hominins weren't also experiencing some form of grief and some kind of some kind of feelings around deaths in the group, and that sort of then leads you to like funerary behaviours and sort of do it doing something to sort of say goodbye to this this person. And one of the troubles that we have with this is that funerary behaviours vary enormously, and so some of them you can when you f you can sort of find them in the fossil record on their there. So the obvious one is burials. If you find like a grave where someone has you know, someone has dug a hole and put the body in it and then like covered it over, that really screams funeral right. So that and there's ex-there's there's some evidence of Neanderthals doing that. There's a cave, there's a cave in Iraq called Shanidar where there's a this apparent flower burial where the there's you know the there seems to have been a pit in the ground, there's a c I think there's a couple of Neanderthal bodies in there, and then flowers strewn over it. There's then this gigantic row about whether the flowers are there on purpose or whether that's like just just just coincidence. But other kinds of funerary behaviours wouldn't leave the same trace. So, for example, if what you do is that you leave the dead bodies deep in caves, that could just look you know, to us, to all intents and purposes, it's just gonna look like a dead person in a cave. It's not it's not necessarily obvious that anything has been done, which is why there's a very large, a very noisy row about Homo and Ledi, which is the South African species, where some of the remains are found really deep in this cave system, and there's and in one case there's this skull seems to have been placed on a shelf, and you and so the people who have been excavating it are are interpreting that as they were burying their dead, and then there was a gigantic row about whether or not that could actually that whether or not that is actually true. It's weird it's it's surprised people because the homo no Ledi brain is quite small. So so some paleoanthropologists will just say, oh, well, yeah, they're just not bright enough to do this. Well, I'm I I I find that vaguely unconvincing, but I also I'm not entirely sure that the evidence sort of nails it either. So I just find myself sort of stuck in the middle, going, uh, it could be either way.

SPEAKER_00 36:27 And well, when we talk about um, you know, this time before we were the last humans left, um, you know, we kind of see our expansion as this you know grand event that happened. Um obviously it happened over a large period of time, and there were there were some cultures of Homo sapiens that tried and failed, right? There's so there's the LRJ culture, uh, which is one I recently found out about through you. So um and and I've just found it completely fascinating. Uh could you tell us about the LRJ people? Yeah.

SPEAKER_01 36:58 So the LRJ is it actually, it's the name comes from uh some unusual stone tools, first of all, that are fat they're they're kind of leaf-shaped, almost almost feather-shaped, actually, to my to my eyes. And they're found in a few different sites in northern Europe. So there's basically there's three sites. So there's Lincoln Hill in Torquay in southwest England. There's a place called the Ilsenhurler, which is a cave near Ranis in Germany, and then there's another cave in Poland near a village whose name I'm about to butcher horribly, which I think, but I think it's Josmanovice. Yeah, so these were so these were called eventually the the Lincomian Rhenician Josmanowician tools, and that immediately got that immediately got shortened to LRJ, because no one's saying that. So these are sort of very widely separated. And so it was always a bit of a mystery as to who was making them, but then eventually in the last few years, um, people have re-excavated the the German site and managed to get some human remains and get some DNA out of them. So that at the German site, at least they're being made by modern humans, by our species, about 45,000 years ago. And the other thing that the genetics tells us is that the population seems to be pretty small. So you when you have like a few different genomes from the same place or from a couple of sites in this case, actually, you can estimate how big the breeding population was. And in this case, there's saying around 200. And that had been sort of steady for sort of several generations. Now, if you imagine the size of area that we're talking about here, that is quite small. So that that sort of figure comes from the the a site in Germany combined with another site in the in the the Czech Republic. So 200 breeding individuals for a for an area of like hundreds of square kilometres. And then once you sort of then extend this to the UK, this seems to be a population that is very widely scattered. You know, then they they can't be living in sort of in big groups, and the neighbouring group must have it must at all times have been quite a long way away. And that probably is a big part of the reason why they don't seem to have survived. So there is no the particular genetic variance that you find at these sites is not found, they are not found in any modern human population. So they they don't seem to have left any ancestry. I think that if you're living in sort of relatively small isolated groups, that's just always a recipe for danger. I mean, that that's not just true of humans, that's true of any species. If you go and look on the the IUCN red list, which is this sort of very authoritative database of endangered species, there they have like lists of things that can pose a threat to a species, you know, like overhunting or like habitat destruction or whatever. And one of the big ones is just you know, populations that are small and isolated. Basically, one stroke of bad luck can wipe out one of those populations, or sort of, or at least leave it in a point where it's where it's essentially doomed. And if there's no neighbour on the other side of the valley, so to speak, that they can sort of go and go and mate with or join up with, they're probably doomed. Whereas if you live in a big network of communities, you know, that you know there's the people in the next valley, there's the people on the other side of there, and there's the people further down the river. You know, that there's kind of always somewhere that you can go. So if you if if your group gets caught in a rock slide and like half of the adults get killed, the rest of you can just go, okay, fine, right? Like go down the valley and um join up with like Jim and Edith or whoever, and uh and and you you've probably been trading with those people, you've probably been like exchanging gifts or whatever, and so you're liable to get that sort of that kind of help. Whereas if you're living these sort of very in these isolated groups, that's just dangerous and it's and just not and not sustainable.

SPEAKER_00 41:01 Yeah, and and I think you know, they were making these incredibly intricate tools, and I think you know, our tool use and incredible brains are uh always obviously associated with our expansion, but um, the tool use alone clearly isn't enough, you know, that ability to fashion things like that. And and it does make me wonder whether before we became the last species of human on earth, whether our survival was inevitable or whether a lot of it was luck. You know, how how differently um could the earth look had another species inherited it? I mean, could they have?

SPEAKER_01 41:37 If you go if you go back, sort of say 50 or 60,000 years ago or 100,000 years ago, and you compare the sorts of tools and other artifacts that our species were making and the artifacts and whatnot that Neanderthals were making, good luck telling the difference. Unless you're a genuine expert who can sort of really pick apart some of the details, it's not meaningfully different. And then as you come into the more recent past and you start to get this expansion of our species, we start making a greater range of things and doing a greater range of things. There's a really interesting study that came out a year or so ago which looked at where modern humans were living in Africa before that, before the great expansion. And while they were living in a wide variety of different habitat types, they weren't living in all of them until about 70,000 years ago. Take that date with a bit of a pinch of salt, but around about that time, they start to move into basically every sort of different variant. So yeah, they're not just in like the tropical rain, you know, because people sort of say, oh, rainforests. There's loads of different types of rainforests, and modern humans were living in some of them, but not yet all of them, and then after a while they were. There's not an obvious technological shift that's going on there. Um, and one of the things that again just keeps coming up is is this just to do with population size and connectivity? That if you're just if you're living in a sort of large meta population, you you've got your group of like maybe a few dozen people, and then there's another group in the next valley, and you're and you're and there's a few others that are dodged around you, and so you're you're sort of connected to this web of communities, then ideas can spread, and like yeah, if if a if a useful mutation happens to arise, obviously you're not going to be conscious of that, but it can spread through intermarriage. That seems to be just an absolute engine for um sort of development and expansion and creativity. Whereas if you if you are sort of living in these small groups, you are basically just sort of trying to get by from day to day. You don't actually know you might you may not just have that much time to do like wildly creative things, you don't and you don't have much of an opportunity to take a risk because you will just sort of think, you know, if I do that, I'll probably die. Yeah. Let's not do that. Um, but sometimes those risks are really yeah, the sometimes but sometimes risks pay off, right? Yeah, it it's it it's good to have that freedom, or to or for some members of the group to have that freedom to just go, you know what's yeah, we're gonna try and raft that river. Like maybe, maybe this is gonna go wrong.

SPEAKER_00 44:17 We are gonna be the accessors of people who took very dangerous risks.

SPEAKER_01 44:21 Yeah, sometimes. I mean, somebody had to get to Australia. Yeah. Um that was you know, there are multiple sea crossings involved in that, and some of them fairly hairy. Uh, somebody had to get to the Americas, and again, I you there was a land bridge because the um it was an ice age, and so that there was literally like it was frozen though. It was frozen, it was frozen. On the other hand, it was frozen. It was really cold and dangerous, and there were polar bears and stuff. Um, but yeah, but so somebody did that. I do sort of keep coming back to the idea that one of the reasons that our species is around and the others weren't is not. Due to any particular like innate greater intelligence, because I just you just can't see that when you compare our artifact records to the Meanderthals, you just can't see that. And I also don't see it as being to do with um aggression, uh, because that again that just doesn't show up. The thing that does seem to show up is um this larger population sizes and sociability. Yeah. And I do th and I do think that like one of the a really defining human trait that sometimes gets overlooked is just our ability to get on, at least sort of in a sort of vaguely polite way with a large number of people. You know, the fact is that you're if you you can walk down the street and probably not get into a fight, and you probably won't see one. Maybe if you go out on a Saturday night in the wrong pub, you might see a f you might you might well. Um It's more amazing than it really than you realize, isn't it? Actually, yeah, it is because when you compare you compare a chimpanzee society, they fight all the time. Um there's a lot of violence. Um humans are relatively friendly and relative and and relatively sociable. And I do think that that that's a that has been an underrated thing. God knows why. I sometimes I just blame Stanley Kubrick for this. For like open opening 2001, where like yeah, the the the first tool that the ape-man invents in the film is like is a club, right? And he and he and first of all he goes and kills the tape here so he can eat meat, and then he goes and murders the rival from the other side of the pond. Um I Stanley, I get it. You know, building new and better weapons is not necessarily progress. I get what you were saying, but I'm not actually sure that that was the first tool was that was like a weapon. I'm d I'm not convinced by that at all. There's a sort of equally compelling argument that the first tool may have been a baby sling. Oh you know, the thing is you're gonna make it out of you know some sort of soft vegetable matter that's not gonna preserve, so you you were not so we don't necessarily expect to find it. But um, but it's very logical. Yeah, it's uh yeah, they're uh they're almost universal. You go to a hunter-gatherer society or a foraging society and they're still using baby slings. Humans lost our body hair several million years ago. Exact date TBC, but yeah, we lost our body hair, which means that babies can't cling. There's nothing there's less to cling to. And also in any case, our babies come out really helpless, so they can't really grip uh and hang on. So you either have to carry them physically, which means that your hands are no longer useful to you, or you put them in a sling, uh, in which case you still have you can sort of walk around with your baby attached to you and still do stuff. We're we're sort of always slightly constrained by the things that we can find, right? And like stone tools preserve because they're because they're made of rock. And so and so hence we have this term the stone age, um, because that's what we've can find. But it's ridiculous to think that that's all that they were using as tools, or even that it was the majority of it. I'm sure that I'm not I'm not trying to sort of say that stone tools were important, of course they were, but like a a whole bunch of other stuff got made too, and we just and we're way less likely to find it.

SPEAKER_00 48:10 Um recently you you looked into the extinction of the Neanderthals, and it could have been uh after uh a sort of a cold spell decimated populations, there was a lack of genetic diversity, and it just meant that they didn't have the population sizes or the genetic diversity to keep to keep going, basically. You know, this is this whole story that maybe they weren't driven out by Homo sapiens, but were instead um, you know, just fell prey to the environment. But if that hadn't happened, you know, my final question is is there a version of history where Neanderthals are uh dressing another Neanderthal up as a Homo sapien, putting them on a putting them on a train and seeing if they get a funny reaction? Like, I don't know, but I don't think it's a ridiculous idea, right?

SPEAKER_01 48:55 Because if that story that I just told about um increased population sizes and connectivity and sociability is really the explanation, then the question just becomes, well, could Neanderthals have gone that way? How could they have developed that degree of sociability and friendliness for want of a better term? And I don't know. It's a it's a it's one of those really open questions. We know from their genetics that they did tend to live in like relatively small groups and that their effective population size was never that enormous, even though they're ranging over a really wide area, which kind of makes you think, well, maybe that's just some that you know, there's something in build uh about them that they're just they're just kind of wired that way or they're genetically that way, or whatever you want to call it. But that is in itself, I think, a kind of speculation. I and and even if that was the case, well, maybe they, you know, maybe a handy mutation could have cropped up that made that that made them less wary of one another or whatever, and or maybe they could have just had a cultural shift. Uh and so you know what, all this hanging out by ourselves, you know, it's a bit rubbish, isn't it? Let's go, let's go and spend more time with the neighbours. I think it's in yeah, it's entirely possible to me that like yeah, that that they could have just changed their behavior in so in some key way just a little bit earlier, and the whole of the whole of the last 50,000 years would look very different, and the planet would look very different now.

SPEAKER_00 50:19 Well, I I'm picturing this amazing Earth now, and and I do wish I could experience it. And there's so much more I could ask you. But Mike Marshall, it's been a pleasure talking to you. Thank you for joining me on what we did before. Oh, thank you, Ollie. A massive thank you to Mike Marshall. I really hope you enjoyed the conversation as well. This is what we did before. I'm Ollie. Please subscribe to the show, it really helps us out, and I will see you next time.