New Discovery Reveals the Secret Lives of Denisovans

0:01Low energy, unfocused, foggy, you might be dehydrated. Whether it's hot yoga, over 100 degree weather, or too much sun. Gatorlite, with a specialized blend of five electrolytes, was scientifically designed to help move fluids into the body faster for rapid rehydration. Shop now at retailers nationwide. Gatorlite hydrates faster than water. Is it in you? Symptoms noted are signs of mild to moderate dehydration. Consult a healthcare professional if symptoms persist. It's an extraordinary time for discoveries about human evolution. Golden age. It really is. And over the last few years, we've had discoveries that suggest that at least four other species of human were alive as recently as only 50 ,000 years ago.

0:44Now, we've suddenly got a trove of evidence that one of these groups, the Denisovans, lived in southwest China for over 100 ,000 years. And it's the first evidence of Denisovans in that region and one of the only known sites with artifacts that can tell us how this really close relative of ours actually lived. From New Scientist, this is the world, the universe and us. I'm Dr Penny Sarchet. And I'm Dr Rowan Hooper. And now I was reading about ancient humans before we came on the show and I saw this quote from the anthropologist Claude Levi-Strauss. And this is about Neanderthals, not Denisovans, but he said Neanderthals have been good to think with.

1:21And what he meant by that was it makes us think about all this Neanderthal stuff we've had over the years. it's made us think about human identity, but also about race, about species, what they are, about gender roles, but especially about human exceptionalism. And that's the idea that we're something special. And, you know, it's only us that can make tools and have culture, have language. Yeah. And we know now that Neanderthals had art. And what does that mean about humans and art and what art is? That's just one of the reasons that all of these new discoveries we're making about ancient humans are so thrilling.

1:56so exciting. And that's what's especially cool about this latest discovery, which is telling us more about the technology that Denisovans used and how they lived. And to tell us about that, we've got science writer Mike Marshall here. Mike. Hello. Mike, tell us about this new study then. Yeah. So this is an excavation in southwest China at a place called Bianfu Cave. It is one of the best archaeological records of the Denisovans that has ever been found. there are over a thousand artifacts which compared to some of the other places where we have Nisman evidence for that is an absolute treasure trove is an enormous amount of material and so we actually have a bit of a sense of how they were living you know what kind of tools were they making what were they using them for and what were they hunting so you can actually start to get a sense of these people's lifestyle which was which we really knew very little about before.

2:47And so let's step back a bit and say a hundred thousand years ago could you tell us about the different kinds of humans that we were sharing the planet with back then? It was a busy time. So there were multiple different ancient human species, hominin species living on Earth at that time, sort of sharing the planet and sometimes meeting with each other and interbreeding. So our species, modern humans, homo sapiens, have already evolved. They're mostly still in Africa, but a few of them have started meandering out like into the eastern Mediterranean and Arabia, places like that in europe and western asia there's the neanderthals who have been you know who have been there for a couple of hundred thousand years at that point they're very well established and then in the more eastern part of asia like what we would now think of as china russia and that those that sort of general area is the denisovans and the denisovans are this really quite mysterious group because they were the first hominins to be identified through their dna rather than by like finding a convenient skeleton to sort of show us who these people were there was just like a little a single bit of like finger bone found in this place called denisova cave in the altai mountains of siberia and a genome you know there was preserved dna in there and it was they were able to read the genome of this and say oh yeah this is not a neanderthal it's not a human it's not a modern human it's something else and that's how this this group the denisova sort of came to be known and then in the 16 years since then we've been people have been basically trying to find you know actual remains what they actually look like and their culture their material culture and that this is what we're finally getting a bit of a glimpse of yeah because we had that we reconstructed their face the other day didn't we not the other day but like recently recently on the podcast we talked about this because we found the skull and they did a face reconstruction so we are getting a lot more information about them yeah it's coming together slowly but surely uh finally a proper skull was found that's in that's from northern china and then there's been a few other bits that have been sort of dredged up from like the Taiwan Strait.

4:42And there's various other fossils that were actually known from before, like in China and thereabouts, which people have since gone, oh, actually, we never quite knew what that was. We could never quite make sense of it. Maybe it's actually a Denisovan. So yeah, slowly but surely, they've been coming together. And we are getting a bit of a geographical shift, aren't we? Because, you know, they're named for this cave in Siberia, and there were some cool studies of Tibet. But increasingly, these new findings, they're centering on China. And this is the first artifact so far that we've had from southwestern China?

5:12That's right yeah this is the first evidence of the Denisovans from southwestern China which southwest China sounds like a small place it's not it's huge we're talking about a massive area and this is this is the first time they've been found there people I think the the archaeologists kind of expected that they would be there but it's just taken this long to find them the Denisovans are sort of odd because we actually kind of discovered them backwards in a way like Denisovans cave itself is quite far north it's cold it's a difficult kind of place to live and it's probably on the edge of their range and actually probably their sort of real heartland was probably china what we now call china and like the neighboring countries where you know it's a more temperate or tropical climate and you know much easier to live in it's just that it's taking yeah having discovered them at the edges of their range people have now been trying to find the uh the center of where they lived and this is a this cave so we said they've been they were there for a hundred thousand years that's a long time to be in one location.

6:07And Penny said it was a trove of, there's thousands of bits and fragments of bone and an artifact they found, haven't they? What an undertaking to go through all this stuff. Oh God, it is an enormous amount. So it's over 64 ,000 fragments of bone and over a thousand stone artifacts of one kind or another. That's a lot of PhD students on that, isn't it? There's a lot of legwork. You could not get me with wild horses to go through all of that lot. And an amazingly lucky find as well, because this whole area was being quarried. So the cave, the quarriers had already demolished the entrance to the cave.

6:46Quite a lot of it had been destroyed when some of the local workers spotted some of these animal bones and thought and reported it to the authorities. And the archaeologists basically had to do what's called a rescue excavation, where they just came in within a few months and just dug up everything that they could find. in haste before the uh the developers moved in yeah yeah basically uh so we probably there probably was even more there which unfortunately has you know by bad luck has been lost but through these people's efforts that we've managed to get still a huge amount and so this is bianfu cave in yunnan province could you tell us um what sort of time period these fragments uh are covering So the hominin remains, there's bones and teeth from the Denisovans, and those are between 134 ,000 and 167 ,000 years ago.

7:36But the actual stone artifact record is actually longer. So there's artifacts as early as 190 ,000 years ago and as recent as 70 ,000 years ago. So that put 120 ,000 years roughly in total. So they found a location they liked, and there must have been something good about it. And we can start to get an idea about it, can't we, actually, because of all the things they hunted. And so we start to learn about their subsistence culture and, well, their culture in general. Yeah, that's right. So we know from the pollen that was found in the cave that this was an area that was like lots of conifer forests, a certain amount of steppe, like grassland territory, nice temperate climate.

8:17One of the researchers at one point, I think, sort of described it as like Denisovan paradise. It would have been, I think it was quite good living. So among those animal bones in the cave, they found a lot of deer, cow-like relatives, sheep and goat relatives, and also some rhinoceroses and hyenas, which would have been a bold choice. But the deer and the cows were like the main thing that they seemed to have been hunting. And a key thing that sort of comes out is that they were hunting the animals that were in their prime of life. So they weren't reduced to sort of hunting the sort of older animals that were perhaps weaker or like the small, younger animals that were easier to catch.

8:56No, they were going for the prime, full-sized animals in excellent health and they were getting them. Yeah, these aren't people scrabbling around for a living. This feels like an empire, Mike, right? They had a 100 ,000-year empire in this region. What an incredible – and they were catching snow leopards. Maybe that was in Nepal, though, wasn't it, or Tibet? Yeah, there's another Denisovan site up on the Tibetan plateau, and there's evidence there that they were actually mostly catching blue sheep, but they sometimes seem to, of course, know that as well. Blue sheep. Blue sheep tonight, lads. But what an empire.

9:34What a 100 ,000-year stronghold. And they feasted on rhinoceros. These are a sophisticated people. yeah no they were they they clearly you know had a really good um understanding of like the you know the ecosystem that they were living in and like how these animals how the animals were moving and like how to get them because they have but you know prime age animals are not easy to bring down and they would they seem to have been doing it routinely the weird thing is that the the stone tools that are found there the the thousand dollar stone tools are actually quite sort of simple and basic it's mostly just like you know a chunk of rock that they've like knocked a sharp flake off which you can then use for cutting but it seems that they just didn't need to use any any at least any more complicated stone tools they it's quite possible they were using a lot of wooden tools like bamboo tools and other things that haven't preserved there are some bone tools in the in the in the cave that have survived so it may well be that these were sort of because they were using other kinds of tools that don't preserve we sort of we see a little bit less of their material culture than perhaps we'd like but it's it yeah you shouldn't be sort of misled by the simplicity of the stone tools that's probably more just to do with like the expedience of where they were living that they just had other things that they could use and they clearly were making good use of them low energy unfocused foggy you might be dehydrated gatorade zero powders have been scientifically designed to help improve hydration balance in the body with a clinically proven

11:19What about genomics, Mike? Because I know we've recently had the second Denise van Genome sequence, but if you go back to Neanderthals, which we've sequenced quite a lot of them now, I think they can say that Neanderthals and modern human sapiens are 99.8 % identical in terms of genetic sequence. But what do we know about Denisovans? So Denisovans seem to be kind of about as similar to us genetically as the Neanderthals were. There's a bit of a debate as to exactly what the relationship is between the three species. But the genomic evidence would suggest that there's like some ancestor at some point a long time ago.

11:58and it splits first of all into the ancestors of Denisovans and Neanderthals on one side and the ancestors of our species on the other side. Neanderthals and Denisovans are sort of sister species. And actually the researchers at this cave, they managed to extract some proteins from some of the remains. They didn't get any DNA, but they did get proteins. And the protein evidence that they have matches that evidence from the genomes that again, Neanderthals and Denisovans are more closely related to each other than they are to us. But that said, we then interbred with them, didn't we? So people of European ancestry have some Neanderthal in them.

12:36And then people of East Asian ancestry can have quite a high proportion of Denisovan. I say high, we're talking 12 % maximum, aren't we? Yeah, I think that there's sort of relatively low levels of Denisovan ancestry in mainland China and thereabouts, like on the Asian mainland. And then there are places in Ireland, Southeast Asia, where there is slightly higher levels of Denisovan ancestry. And no one is quite sure what that is. It may be the result of past migrations. Or it may be that the Denisovans actually went to some of those places. And we just haven't found the fossil evidence of them yet.

13:12But certainly, genetically, they are very similar to us. And a lot of the technology that they're doing is quite similar to what modern humans were doing at the time. Yeah. So we've been calling them different species, Neanderthals and the three species. But, you know, they were interbreeding and it does bring up that old question of, well, when do we say they are a separate species? Yeah. And honestly, I think it's just a matter of like convenience and labelling at this point. No one has ever really been able to agree on what a species means. So one definition is that two animals belong to different species if they can't interbreed anymore.

13:49but in that case there would be an awful lot of modern animals that you would have to say oh actually those aren't separate species after all there are like i think there are about a half a dozen species of baboon but they can all interbreed with each other they just don't often do it because they don't meet yeah i think in the in these cases in the case of like humans neanderthals and denisovans they they look distinct as far as we can tell you know they have differences in the skeletons genetically they're reliably distinct you can tell if you get a genome which one it is and they seem to have some behavioral differences and crucially they just live in different places but when they do meet in these sort of um junction zones uh where you know where they where they butt up against each other they do seem to uh uh do a certain amount of interbreeding and hence hence why so many people today have a bit of neanderthal dna or a bit of denisovan dna yeah i think it's just going back to this thing about human exceptionalism and and we are like we could we could interbreed um what we know so far is only only 0.12 percent difference in genes between us and neanderthals like very very little but the differences in how the genes are expressed um and that's extraordinary isn't it we may look we look different genetically very similar but the way they're expressed look at what happened like when they are expressed we we did turn out very differently and well i'm i guess how different were we really well we did have we were better at making tools right i i'm kind of am leaning towards some sort of exceptionalism because you you have to look at what what humans did and what the others couldn't do right although like they were in this place for 120 000 years have we managed that anyway yet mike that's yeah yeah Yeah, Africa and the Middle East.

15:36Yeah, sure. Right, okay. But I think that a lot of the differences in the tools and technologies that our species wind up making are more to do with having larger populations so that knowledge can spread and be built on, rather than necessarily being more creative or individually intelligent. There doesn't seem to be much, in as far as we can tell, for a long time, these different groups were all making very similar things and living in quite similar ways. But at some point, the modern human population just gets bigger and more connected. Whereas the Neanderthal population, for a long time, there seems to have been quite small groups that don't interbreed too much with some of the other groups.

16:17There are some groups that seem to have been isolated from the rest of the Neanderthal population for thousands of years. For whatever reason, they seem to have seen themselves as distinct from the rest and didn't interact with them. And if you don't have those sorts of interactions, then that's sort of less opportunity to learn, to get ideas and to have that sort of cumulative buildup. Someone innovates a bit and then somebody else builds a bit on top of that. You need groups really to do that. You need big groups and interaction. And if there was less of that in some of these other groups, that may be why their technology didn't develop in the same way that our species did.

16:51Humor me, Mike, if we were going to sort of flatten us all into stereotypes, I get the impression of Homo sapiens' very social connectedness seems to have been our success. The Denisovans were getting this picture of them as being very adaptable. You know, they ate loads of different things and lived in all different kinds of places. Well, Neanderthals have come under a complete sort of revision. You know, we used to think they were kind of big and ugly and stupid. We now know they had sophisticated culture. You know, how would you stereotype the Neanderthals now? I'd stereotype them as being very creative, but possibly a little bit unfriendly to strangers, distrustful of strangers.

17:30Interesting. In a way that our species doesn't sit. Not that we're not sometimes very distrustful of strangers, but it's perhaps a difference of degree. I think the Denisovans are slowly coming into focus, so it's harder to give a stereotype from them. But the one thing I think we can say is they were big because the few fossils that we have suggest that they were like American football player build. So unless we've got some like exceptionally large individuals and like just by sheer chance, then probably, yeah, they were big people. So, yeah, I mentioned that, you know, we now know that the Neanderthals did art like we do, like we do and also did.

18:10Do we have any idea if the Denisovans were at it as well? Is there any such thing as a Denisovan cave painting? Not that can be confirmed, but there is some tentative evidence. So at a site called Lingjing in China, there are a couple of bone fragments which have like scratches on them, like etchings, I think just parallel lines. And those are about 100 ,000 years old. So nobody quite knows who made them. There is a skull of a hominin from the same site, but it hasn't been identified properly. No one quite knows which species it is. So it's distinctly possible that it's the Denisovan and that a Denisovan was the one that carved those lines onto the bone fragments.

18:49I mean, I would not be surprised. In Denisovan cave itself, there are some quite amazing bits of prehistoric jewelry. The problem is that modern humans and Neanderthals lived there as well at different times. And so it's really hard to tell who did what. but it's at least possible that some of it is made by the Denisovans and given that the Neanderthals seem to have been doing it and there's even evidence of like an earlier species Homo erectus doing just basic scratching on shells I think about a half a million years ago it would not surprise me at all if it if it did turn out that the Denisovans made art.

19:21There was this stone that was brought into a cave by an Australopithecus so that's like maybe a million years ago and the stone's got a face on it like just naturally it occurred to have a face and the inference is that this australopithecus picked it up and thought hello and i'm going to bring that to my cave and and so that that was not made art but it was some recognition found objects and that that gives me the chills like that's a long time ago and um i mean this year i went to the um vr cave in the dordogne in france and so the there's cave art there that you can actually go right up and see it and so this is only 17 000 years old um but to see the art on the wall of there and and there's a there's a famous one there's a bison um and then there's a human sort of confronting it and raising his arms to it like a shaman or something and i just think it's it's it is amazing to see this stuff yeah it is like sort of weirdly jaw-dropping and kind of eerie yeah to be to be in some of these caves because you you sort of realize that you're somewhere that somebody else was wandering around like tens of thousands or hundreds of thousands of years ago and they were looking at the same rock formation and the same stalactites that you are now yeah uh and yeah it is it is you you slightly feel like you're walking through a graveyard yeah um and it's slightly unearthly because you know you've got this like yeah or if you to really get the effect you're meant to go in with a with a naked flame rather than a like electric torch because then you get the flickering of the light which is what it would have looked like and you You can get this odd sense of movement from some of the artwork, which is really quite amazing.

21:00Yeah. And I like the idea that maybe this person in the drawing was showing respect or some sort of awe in front of this bison. But that's what we were doing as tourists, going into the cave, also looking at their art and doing it thousands of years later, going, oh, yeah, paying our respect to these ancient artists from the distant past. at the start Mike we mentioned that there were four types of human about 50 ,000 years ago what was the fourth was it the hobbit uh yeah hobbits yeah so they they were the little meter high people that lived on Flores yeah okay in Indonesia yeah that's right and then for so long you know we had very little to go on with Denisovans there was the jawbone bit of DNA and we were waiting for more artifacts or skull what's the next big thing you hope we'll find or the the big question now for Denisovans it's a slightly sideways thing I really want someone to get uh molecular evidence like DNA or protein I don't care which from a Homo erectus fossil if at all possible because everyone is increasingly convinced that one of the things that the Denisovans did was to interbreed with Homo erectus which is an earlier species of hominin and like the first one to as far as we know the first one to come out of Africa and and who were around in East Asia for a very very long time you know until a little over a hundred thousand years ago so it's they would have met the denisovans it's it's it seems impossible that they didn't and so i'm really keen to find out what happened when the denisovans and the homo erectus met and if they actually and if they really were interbreeding because i think that would yeah that's one because that then sort of starts to extend this story even further back into deep time that these you know these human these human species have always been kind of jostling up against each other and meeting each other and having these uh wacky adventures that we're only now sort of being able to piece together fantastic thanks mike thanks to our guest mike marshall that's all for this episode and thanks to you for listening do follow and subscribe wherever you get your podcasts goodbye for now bye Bye.

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