Human Origins: Did We Begin in Africa?

The story of human origins is often imagined as a simple journey from Africa, but is the truth actually much messier? Tristan Hughes and leading palaeoanthropologist Prof. Chris Stringer dismantle the traditional narrative, discussing how recent breakthroughs in fossils and ancient DNA reveal a complex, shifting history of multiple migrations and cross-breeding to uncover where we truly come from. MORE The First Britons with Prof. Chris Stringer Listen on Apple https://podcasts.apple.com/us/podcast/the-first-britons/id1520403988?i=1000590938176 Listen on Spotify https://open.spotify.com/episode/5cKCCdeptxhxOMRD8HGavq Rise of Humans Listen on Apple https://podcasts.apple.com/gb/podcast/rise-of-humans/id1520403988?i=1000702067254 LIsten on Spotify https://open.spotify.com/episode/1vXxIXCruQh4w90EuawE6E Presented by Tristan Hughes. Edited by Aidan Lonergan. The studio manager is Hanif Hussain. The producers are Joseph Knight and McKenna Fernandez. The senior producer is Anne-Marie Luff. All music courtesy of Epidemic Sounds The Ancients is a History Hit podcast. History Hit is part of Little Dot Studios, a Certified B Corp™ The Ancients is now on YouTube! Watch HERE https://www.youtube.com/@TheAncientsPodcast Want even MORE Ancients? Sign up to History Hit for early access ad-free, plus exclusive subscriber-only episodes. PLUS with a History Hit subscription you can watch hundreds of hours of original documentaries, with a new release every week. Sign up at https://www.historyhit.com/subscribe. Hosted on Acast. See acast.com/privacy https://acast.com/privacy for more information.

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• 0:00Tristan Hughes?

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• 2:39Speaker 03

  I'm Connor Tomlinson from Love on the Spectrum. History is my thing, and I've been waiting my whole life for a show like this one. And I'm Carter Roy, and this is What the Fact? Three facts a week, each with the whole story behind it. The history class you actually wished you had in school. New episodes every Wednesday. Follow What the Fact wherever you listen or subscribe on YouTube at What the Fact Pod.

• 3:09Tristan Hughes?

  The story of modern human origins is often imagined as a simple journey out of Africa. Homo sapiens emerging somewhere on that continent before spreading across the world and replacing other forms of human life. But how is that story still evolving? Is the fall of truth of our beginnings actually much more complex? Over recent decades, evidence in the form of fossils, improved dating, and ancient DNA have transformed the traditional picture, revealing a deeper, much messier tale of shifting African populations, multiple migrations, and sister species like Neanderthals. I'm Tristan Hughes. This is The Ancients.

• 3:52Tristan Hughes?

  And today I'm joined once again by leading paleoanthropologist Professor Chris Stringer to explore what the out-of-Africa theory really means today, why it still matters, and what exciting new discoveries could still be revealed about where we come from.

• 4:22Tristan Hughes?

  Chris, it is such a pleasure to see you again. Welcome to our new studio.

• 4:26Speaker 04

  Yeah, it's great to be here. Looks great. Yeah.

• 4:29Tristan Hughes?

  And well, we couldn't think of anyone better to come on the show to talk about human evolution and our story and the fact that Africa was, and still is, I guess, the mothership for our species.

• 4:40Speaker 04

  Yes, it still is the main place. But obviously, the more we learn about some of these other places, particularly places like China, we realize that they're an important part of the story, too.

• 4:51Tristan Hughes?

  And I guess it's, as we'll delve into, there's going to be quite a science-y chat and how the out-of-Africa theory, it has developed a lot over the decades, hasn't it?

• 5:00Speaker 04

  Yes. I mean, since even the 1970s and early 1980s, when I and a few others were proposing this, very much a minority view then, it was a very simple version that we had, based on really slender evidence. And it's developed so much now, particularly obviously with the DNA evidence, but also new fossil discoveries and new methods of dating things.

• 5:22Tristan Hughes?

  And so for how long then has this idea, this proposal that Homo sapiens originated from Africa, how long has that been around?

• 5:32Speaker 04

  Well, I and a few others started to tentatively propose it in the early 1980s.

• 5:38Tristan Hughes?

  1980s, okay.

• 5:39Speaker 04

  And it was based then just on the fossil evidence. But there was so much we didn't know, there was so much uncertainty, that it was put forward very cautiously. And then in 1987, of course, we had the story of mitochondrial Eve appearing, which argued purely from recent DNA evidence, mitochondria, mitochondrial DNA inherited only through women. It argued that everyone in the world today could trace back their ancestry to a woman who lived in Africa maybe 200,000 years ago. And this was based purely on data from present-day humans. But it matched obviously very well with what some of us were saying.

• 6:20Speaker 04

  It gave an even clearer and apparently more confident picture that we had a recent African origin.

• 6:26Tristan Hughes?

  I just wanted to ask that because I was wondering if anyone had potentially put forwards that theory before the 1970s and the 1980s, but it does sound like that was actually where it really...

• 6:35Speaker 04

  Yeah, that was the beginning. I mean, people like Bill Howes, the anthropologist, he had argued for quite some time before that, that Homo sapiens was so different to the other things, the Neanderthals and so on, that we probably had a different origin and a single origin somewhere. But when he was proposing that, even in the 60s and 70s, he couldn't say where that place was. And it turned out later, of course, that it was Africa.

• 7:01Tristan Hughes?

  And when talking about a recent African origin, what time period should we be thinking of roughly?

• 7:07Speaker 04

  Yes, well, the main exit that leads to the diversity of people today outside of Africa happened, geneticists estimate, around 60,000 years ago. So Homo sapiens, having evolved for a long time in Africa, a small group got out of Africa and then founded the populations of the rest of the world. So that's the kind of recent out-of-Africa bit of the story. And we now know that it's more complicated than that, that there were some earlier exits of Homo sapiens out of Africa that didn't end up giving rise to the populations today. And also, we know that it wasn't a pure out-of-Africa. You know, some of us argue that it's virtually 100% recent African origin.

• 7:52Speaker 04

  But now we know that other humans contributed to our ancestry. People like Neanderthals, Denisovans, which we'll come on hopefully to talk about, they contributed a bit to our ancestry as well. So now I use the term, which I think was first used by Sfanti Parbo, mostly out of Africa. I think that's the best way of describing it for Homo sapiens origins.

• 8:14Tristan Hughes?

  And I guess also, is it, this is also something I find fascinating, the fact that actually our story, our Homo sapiens story, the majority of it is before 60,000 years ago. So there is a lot of archaeology still to be found in Africa itself, do we think, to kind of trace that earlier story of Homo sapiens?

• 8:31Speaker 04

  That's right, yes. The main part of the story earlier on is certainly an African story. And probably a lot of our behavior originated in Africa as well as our anatomy. And certainly, most of our DNA comes from that African ancestral population.

• 8:48Tristan Hughes?

  One other big question, first of all. We say things like anatomically modern humans and archaic humans. What do we mean by that?

• 8:56Speaker 04

  Yes, those terms, I've used them a lot in the past. I'm not sure they're very good terms, but they're certainly widely used. And so we better sort of go into what they mean for most people. So yes, our own species, Homo sapiens, if we look at people around the world today, yeah, we come in many different sizes and shapes and colors. But if we strip away the superficial features of the skin and hair and so on, get down to the bones and the teeth, the things that preserve in fossils, there are certain shared characteristics that we can call anatomically modern human characteristics. And so I've got an example of a, that's a replica here.

• 9:34Tristan Hughes?

  Fantastic.

• 9:34Speaker 04

  Of a fossil from Romania that's over 40,000 years old. But here it is with a lower jaw actually from a separate individual. But they show the features of anatomically modern humans. So in the brain case, it's high and rounded, small brow ridge at the front, or maybe no brow ridge at all, quite a small face tucked under the brain case. Um. It's quite narrow at the base and expanded higher up. So the whole brain shape is different. Um. And when we look at the lower jaw, we can see there's a nice chin on the front. And if we had the whole skeleton, we would see that that too is distinct, that there is a narrow pelvis in Homo sapiens.

• 10:19Speaker 04

  A narrow shoulder girdle, um, we're much heavily, much less heavily muscled. So anatomically, you know, we've got more gracile skeleton, if you like, we're slenderer than those earlier species. Which mainly seem to be built for strength and power in their skeletons. So those are the shared features that we can look for, and there are many more of them. If we take C T scans, even inside the ear bones. Um. We can see that the ear bones of Homo sapiens are distinct from those of Neanderthals. So even these tiny little bones. That we can't even physically get to except with C T scans, they're even distinct in Homo sapiens than from people like the Neanderthals. So that's the anatomically modern.

• 11:00Speaker 04

  And archaic is used as the the flip side of that. So the things that don't show those features are called archaic humans. Uh. And that would cover the Neanderthals and Homo hydeobegensis and Homo mantecessa, Homo erectus. They're all called archaic humans. I don't think it's a good term because of course it's a big lumping term covering a huge amount of diversity. And actually, the Neanderthals are not, in some ways, they're not really archaic. They're they're very evolved as we are. So if we look at Neanderthal evolution, we can see that they evolved bigger brains as we did, their teeth got smaller as ours did. Um. So they underwent changes too, and they're actually derived i- in their own direction and as we are derived in our.

• 11:43Speaker 04

  And our direction. So I prefer to talk about derived Neanderthals and derived Homo sapiens.

• 11:48Tristan Hughes?

  Interesting.

• 11:49Speaker 04

  Um. But, you know, the terms archaic and anthropomorph modern are still around and, yes. As a shorthand, I talk about modern humans, by which I mean things that in the skeleton show these sorts of features.

• 12:02Tristan Hughes?

  Yes, because I have other terms here like derived humans and basal humans as well.

• 12:06Speaker 04

  Yes, and so in terms of archaic, I I've tended to try and use the term basal. So these are things which are, you know, if you like, if we had an evolutionary tree, they'd be closer to the base of that evolutionary tree. They show, they show more primitive features. So we've got an example here of a skull from Jebel Ihood in Morocco, we've got a replica. But this one is about three hundred thousand years old. And um I call it a basal Homo sapiens. So it doesn't show all the features of anatomically modern humans, it shows some of them. So for example, here, the brain case is still quite long and low, and there's still a strong brow ridge. But the face, and if we had the teeth and the lower jaw, you can see there, there are some Homo sapiens features.

• 12:49Speaker 04

  But they're not fully developed. So this for me will be a basal Homo sapiens.

• 12:53Tristan Hughes?

  And this is, this is the key point, isn't it? A human skull from, and we'll explore Jebel Ihood a bit more in in time. A Homo sapien skull from three hundred thousand years ago, years ago, can look very different to one four hundred thousand years ago. And the same in Neanderthals, early Neanderthal compared with late and so on.

• 13:07Speaker 04

  That's right, yes. If we had an Atapuerca fossil here from four hundred thousand years ago, uh, from Europe, from Spain. That would show, it's what I call a basal Neanderthal. It shows um some Neanderthal features, but it lacks some of the features of the late Neanderthals. For example, the brain's smaller, the teeth are a bit larger. Um. And also, there's even D N A from the Atapuerca fossils at four hundred thousand, showing that they are early members of the Neanderthal line. Sadly for Jebel Ihood, we don't have D N A, uh, D N A, of course, in an African environment, doesn't survive so well. So. Whereas we've got quite good early Neanderthal D N A, we don't have really any D N A of early Homo sapiens in Africa, unfortunately.

• 13:50Tristan Hughes?

  And all this evidence that is coming to light now, I'm guessing the uh more, I mean. The previous view, the theory that we descended from Neanderthals or Neanderthals came before Homo sapiens. That's now been very much pushed aside.

• 14:07Speaker 04

  Yeah, so the idea that we evolved directly from Neanderthals, that was something I was testing in my P H D back in nineteen, I finished it in nineteen seventy four. And one of the views I was testing was this view, which was a very common view then, maybe the dominant view. Was that, yes, we evolved directly from the Neanderthals and people like them around the world. And so if we had a complete fossil record in Afri- in in Europe. We would see Neanderthals gradually changing into Europeans of today. So the brow ridges would get smaller, uh, the teeth would get smaller, the skeleton would get more lightly built. They'd gradually develop a chin on the lower jaw. So we'd have this sequence from Neanderthal to Homo sapiens. I was testing that in my P H D and I could see no evidence for it.

• 14:51Speaker 04

  The Neanderthals seem to be going in their own evolutionary direction as we were. So. In that P H D, I could conclude that we didn't evolve from European Neanderthals, but. At that stage, I couldn't say where we did evolve from. That that came later.

• 15:05Tristan Hughes?

  That came later and that's where we get out of Africa and we're going to that now. Um. We will delve more into, we'll delve into the nerdy details of the particular theories around uh out of Africa. But can you give us uh a bit of an overview right now as to what kind of the key developments in this? Theory, this hypothesis, what these key developments have been over the past few decades?

• 15:30Speaker 04

  Yeah, so um if we go back to the nineteen eighties, when the ideas really started to take off of recent African origin. Um. There already were a few fossils from Africa that seemed to look quite modern at an early date. So there's one in particular from Omo Kibish in Ethiopia. And I worked on that with uh Michael Day and and we did a reconstruction of the skull. And it showed for us modern human features. It had a small brow ridge, it was high and rounded. Uh. There was a chin on the lower jaw. There was also a skeleton, part of a skeleton to go with it, that also seemed to show recent Homo sapiens features. Now, back in the nineteen eighties.

• 16:11Speaker 04

  It was argued by some people that it was at least a hundred thousand years old, and Myrtle and I accepted that dating. And therefore, this was evidence of a Homo sapiens existing, you know, at the same time as the Neanderthals were alive, and it was in Africa. So this pointed to an African origin, but at that time, we didn't have an ancestor for it, we didn't know where that. It it was kind of isolated in a sense in in Ethiopia. It certainly pointed to a recent African origin, but there were people saying, well, it's wrongly dated, or you're overinterpreting the anatomy. Um. There are fossils in China and elsewhere that look like Homo sapiens too and are just as old. So there was just.

• 16:52Speaker 04

  No clear framework to really say that was the story. Um. There was conflicting data. And it took a while for more fossils from Africa to emerge, better dating to emerge. Um. And for some of those other, what seemed to be anomalies in other parts of the world. Got clearer with their dating. So some of those supposed ancient Homo sapiens in China were not actually Homo sapiens fossils. Or they were wrongly dated and were much more recent. So we got clarification of some of the more confusing bits of the story. But it really started to come together, yes, at the end of the nineteen eighties with the arrival of the first bits of D N A.

• 17:28Tristan Hughes?

  D N A.

• 17:29Speaker 04

  Um. From recent humans that started to point to it. Um. And then as the evidence accumulated in the nineteen nineties and the early two thousands, we got this picture building up that. We were pretty certainly, you know, at least in my view, we looked looked like we were, you know, virtually a hundred percent recent African origin. So I was interpreting the fossil data, the behavioral data, the genetic data as all pointing. To a recent African origin with Homo sapiens and one where if there had been any interbreeding with those other forms of humans, it was minimal. So, and I was aware that closely related species can interbreed and I regarded the Neanderthals as a different species.

• 18:10Speaker 04

  That was a view that kind of I started to pick up on with a few other people in the nineteen eighties, that we went back to using. The name Homo Neandertholensis for the Neanderthals, which they'd been given way back in eighteen sixty four. Then for a long time, um, you know, certainly when I was doing my P H D. It was common to call the Neanderthals Homo sapiens. They were regarded as a form of Homo sapiens. So I started with a few other people to argue in the nineteen eighties that actually we should go back to having a separate species name for Neanderthals. And a separate species name for what became Homo hydeobegensis, reviving that name. But I was aware that in modern mammals, for example, you can get into breeding between closely related species.

• 18:55Speaker 04

  So for example, jackals and wolves, brown bears and polar bears. Um. A number of species of monkeys in Africa can hybridize, even though we regard them as different species. So. I thought it could have happened um between us and Neanderthals. We could have interbred. But I thought that it wouldn't have been a normal event, it would be a rare event, and then it happened forty thousand years ago. We're never going to find evidence of it today. Of course, I was wrong about that, because in two thousand and ten. We got the first reconstruction of a good quality Neanderthal genome. That was published in the Journal of Science, and it showed that indeed people outside of Africa. Have around two percent Neanderthal D N A in their genomes, and that's because there was an interbreeding event.

• 19:41Speaker 04

  Maybe fifty thousand years ago, so Homo sapiens came out of Africa in this exit, maybe sixty thousand years ago. Soon after that, they met some Neanderthals, they did some interbreeding with them. And then as they spread around the rest of the world, they took that bit of Neanderthal with them. So. Not only is there around two percent Neanderthal in people in Europe, but it's there in China, it's there in Australia, it's there in Native Americans. So everyone outside of Africa has this Neanderthal component. So. We have this kind of paradoxical situation that we did not evolve from Neanderthals. Um. Which is what I was testing in my P H D, but they're partly our ancestors because we've got Neanderthal D N A. So.

• 20:23Speaker 04

  So it's kind of, you know, they're, they're a distinct lineage, evolving for a very long period of time, hundreds of thousands of years. But not evolving to such an extent, there couldn't still be a bit of interbreeding.

• 20:35Tristan Hughes?

  And not evolving in Africa alongside ourselves until we got, so it's also further evidence for the African origin. So i- it sounds like it's. It's this combination of improved dating over time, the discovery of some really remarkable new fossils.

• 20:49Tristan Hughes?

  And of course, the introduction of DNA and the building up of this incredible DNA database. All of that combined, as we'll explore, helps make it, you know, why in academic circles especially, this recent African origin is so persuasive today.

• 21:05Speaker 04

  Yes, I mean, for me, it's persuasive. Of course, there are still people who argue that it's still an over interpretation of the data, that actually the picture is much more complicated, that we should acknowledge these contributions from populations in the rest of the world as being more significant. So we have models like the braided stream model, which says that the evolution of our species is more like a river, which has many different tributaries that separate off, but then they come together and merge. And this pattern's been going on for the whole of the evolution of Homo sapiens. Probably been going on for one and a half million years. And that really, there's no point in having these separate species names.

• 21:48Speaker 04

  Because there was a bit of interbreeding going on between many of these different branches, that we should call everything Homo sapiens. So it kind of goes back to that view that was around in the seventies and eighties, that actually, let's call everything Homo sapiens, that's essentially genus Homo. So even to Homo erectus back that far, to one and a half, even close to two million years, people argue that we, we really shouldn't call that a separate species, even that should be called Homo sapiens. Now for me, you know, I come out of a paleontological background, I'm in a department with people who work on fossil fishes and fossil reptiles and so on. And the methods they use to establish species in the fossil record are similar to the ones I use to establish fossils

• 22:32Speaker 04

  in the fossil human record. And the level of difference between us and Neanderthals, certainly in my view, and the view of many of them, is at the level which in any other animal would be called distinct species. So I still regard them as distinct species, even though we know there was a bit of interbreeding. But, you know, we, you know, I'm not sort of wedded absolutely to the idea. But it seems to me that if you call all of those things Homo sapiens, you really lose any meaning to the term. Because, you know, how do we describe what is a Homo sapiens? Well, has it got a big brain? Well, not really, because the erectus ones are very small brained, uh, small teeth? Well, not really, because the early ones have got big teeth and

• 23:13Speaker 04

  Denisovans have got big teeth, um, uh, lack of brow ridges? Well, no, there's brow ridges in most of them. Um, so even to say, what is the brain size? What is the brain size of Homo sapiens? Well, it's everything from down virtually the size of a gorilla, up to the huge size of a Neanderthal us. So the term Homo sapiens become meaningless morphologically, I think, if you have this very wide definition.

• 23:38Tristan Hughes?

  Gosh, all the, we're getting deep into those, those theories already, aren't we, Chris? And we won't go into the weeds of what is a species today, because I know that is also, that's another episode in its own right.

• 23:51Tristan Hughes?

  If I, if you may allow me to ask a superlative question, because we have all this different evidence today. But have there been any landmark discoveries that we can say is the strongest evidence that we have today for evidence of an African origin for our species?

• 24:08Speaker 04

  Well, I think it has to be the genetic data, you know, which is not a single thing. Of course, it's a massive data that keeps building up, you know, tens and tens of thousands of genomes, and all of them show that, first of all, if we partition variation in Homo sapiens today, by far, the greatest part of it is in Africa. And there are deep lineages there. And if we look at the variation of people outside of Africa, it's, it's a tiny subset of that whole variation that we find. So just the pure fact of this, you know, huge diversity in Africa and all of the rest of us being a tiny sub-sample out of that diversity really does point to a recent African origin.

• 24:53Speaker 04

  And that's true for the Y chromosome, male inherited, for the mitochondria, female inherited, and for the whole genome. So overall, I think genetic data are the strongest, but we now have a number of other fossils, not just Homo kibish, but there's other fossils in Ethiopia, such as from Herto. Uh, we've got evidence from Southern Africa, from sites like Clas's Rivermouth. So, and we've got the stuff, as we mentioned, from Jebel Ighud in Morocco, and later Moroccan fossils, that all point to the existence of Homo sapiens features at a much earlier date in Africa than we find them anywhere else.

• 25:27Tristan Hughes?

  So Chris, let's explore some of these, these fossil discoveries. And let's touch on the one for which you have a replica and you brought it up just a bit earlier, which is Jebel Ighud. So can you set the scene of where this is what we should be thinking with Jebel Ighud?

• 25:44Speaker 04

  Hmm. Yeah. So, yeah, this is a replica of, of the first fossil that was found. So, you know, this was found, you know, before I'd done my PhD, it was called an African Neanderthal when it was discovered around nineteen sixty. So it's from a, a quarry, a working quarry, uh, in northeast Africa and Morocco.

• 26:05Tristan Hughes?

  And northwest Africa.

• 26:06Speaker 04

  And north, yes, northwest Africa. Um, so there's a quarry there, and in that quarry were sort of cave deposits within the quarry. And a number of fossils were found there, and this is one of the most complete ones that's been found.

• 26:19Tristan Hughes?

  Was it an accidental discovery whilst they were working there?

• 26:21Speaker 04

  It was an accidental discovery. So this was a commercial quarry, and these bones were being found. We don't know if any were found before that that were lost, but there were. So Moroccan scientists did conduct some excavations there when bones were showing up. And this turned up, and as I say, it was regarded by many people as being an African Neanderthal, and originally dated only about forty thousand years old. So when I did my PhD, I was lucky enough to be able to measure this when it was, uh, in, in Paris, uh, before it went back to Morocco. And I could see straight away that it wasn't a Neanderthal, because by then I'd seen a number of Neanderthal fossils in my trip around Europe in nineteen seventy-one. And the face on its own was unlike any Neanderthal face.

• 27:03Speaker 04

  It was like a, a slightly bigger version of our own face. So for me, this certainly didn't look like a Neanderthal. But at forty thousand years old, you know, it, it was also too primitive to be an ancestor for Homo sapiens. So at that time, it didn't seem to be particularly relevant for our origins. It maybe was a a relic persisting from an earlier stage over in a remote area, peripheral area like Morocco. But, um, a team, uh, went back to the site in, you know, from, from about two thousand and fifteen onwards, and did new excavations, and they recovered more material, more fossils, more stone tools, more animal bones, and they did much improved dating work.

• 27:47Speaker 04

  And that showed that these Jebel Ighud fossils, and by then there were a number of different skulls and teeth and jawbones, these were actually about three hundred thousand years old. And the stone tools were very nice examples of, uh, early middle Stone Age tools. So at three hundred thousand years, suddenly this was back in the scene as an important fossil, because it did show, although primitive, it did show some sapiens features.

• 28:11Tristan Hughes?

  And so what do you mean by early middle Stone Age tool?

• 28:14Speaker 04

  Yeah. So, um, yes, we've got these stages of the Stone Age, which archaeologists have set up. And in Africa, we've got the early Stone Age, the middle Stone Age, and the later Stone Age. So the middle Stone Age in Africa is equivalent to also the middle Paleolithic, that's another term, lower Paleolithic, middle Paleolithic, upper Paleolithic, Paleolithic being old Stone Age. So we've got these stages of the Stone Age, and in Africa, the middle Stone Age is the stage that's associated with the beginnings of Homo sapiens, things like Jebel Ighud. And the equivalent stage in Europe and Asia is associated with the Neanderthals.

• 28:55Tristan Hughes?

  Okay.

• 28:56Speaker 04

  And then it's called the middle Paleolithic. Yeah. So yeah, sorry about those technical terms. But yes, the fact that Ighud was associated with middle Stone Age tools also showed complex behaviour. These are very nicely made tools. So it suggested that, you know, again, this was not a backward population in, in a peripheral area of Africa. It showed that Morocco was important in the story of our origins.

• 29:20Tristan Hughes?

  And more work is being done there down to the present day. I mean, all of a sudden, you know, in recent years, you know, redating that is now one of, if not the oldest evidence of Homo sapien we have from Africa, and more to come, hopefully.

• 29:34Speaker 04

  Yes. I, I mean, it's, I don't think this can be the oldest evidence of Homo sapiens, because work I've been doing with Chinese scientists on fossils from China suggests that the roots of the Chinese population that we know as Didisovans, also known as Homo longi, dragon man, that lineage seems to go back at least a million years, um, as a separate lineage. And if that's correct, that also implies that our lineage and the Neanderthal lineage had split off, and that means our lineage and the Neanderthal lineage must also go back at least a million years um, to the, to a common ancestor. So, um, if that's true, then

• 30:17Speaker 04

  Ighud, in fact, is, is actually relatively young Homo sapiens compared with ones that would be at the beginning of that evolution. So this is still very controversial. The genetic data suggests that we had a common ancestor with Neanderthals and Denisovans maybe seven hundred thousand years ago.

• 30:35Speaker 04

  We would suggest on some of the fossil data, it could be at least a million. So this is ongoing work. But it certainly pushes back the ancestry further, even on genetic data. And that means that Jebel Ighud is by no means the oldest Homo sapiens. Uh, there must be some older ones. Either we've already got them and we can't recognise them, or they haven't yet been found.

• 30:54Tristan Hughes?

  Well, that's the thing, that's the exciting thing. Could there be almost a million years of story still to learn about from Africa in the story of Homo sapiens?

• 31:04Speaker 04

  I mean, there must be a deep history then for sapiens to be uncovered in Africa. And equally exciting, really, there must be a deep history for Neanderthals to be recovered outside of Africa, probably. And a deep history for the Denisovans and the Homo longi lineage that's beginning to be uncovered in China.

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• 33:04Tristan Hughes?

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• 33:52Tristan Hughes?

  And then potentially, I guess the next question would be more evidence of earlier ventures out of Africa by earlier, by, right as you use the terminology, more basal Homo sapiens that we don't know much about as of yet.

• 34:06Speaker 04

  Yes, that's right. So of course, the implication would be that is it really only one very late exit for Homo sapiens, or could there be earlier ones? And yes, we do seem to have evidence of earlier exits. So I was involved in studying a fossil from a cave site in Greece called Epidima Cave.

• 34:25Speaker 04

  And a few years back, we published evidence that from that site, there's the back of a skull, which had been considered to be Neanderthal. But on our analyses, it actually looked like the back of a Homo sapien skull. And the dating evidence suggests that it's at least 210,000 years old. And what's intriguing is that after that fossil is in the site, we also have a proper Neanderthal fossil at the site, maybe 30,000 or 40,000 years younger, the Neanderthals were there, and whatever evidence there was of early Homo sapiens had disappeared. So the Neanderthals came back, and that early Homo sapiens population, if it was there, has disappeared now. Not everyone accepts that this is an early Homo sapiens, and we have to be cautious. It is only the back of a skull. What was the rest of it like?

• 35:11Speaker 04

  But on that evidence, it certainly looks like there could have been an early Homo sapiens dispersal. And that actually ties up with some genetic data, because there's quite an intriguing pattern when we look at Neanderthal and Homo sapiens DNA. I mentioned that we have a separation time, maybe of 700,000 years for us and the Neanderthals, based on the whole genome. But when you look at the mitochondrial DNA of us and Neanderthals, that's inherited through females. When we look at the Y chromosomes of us and Neanderthals, inherited through males, they have a younger ancestry, a younger common ancestry, maybe only half the age of what the whole genome would say, maybe 350,000. Now, that's very strange.

• 35:55Speaker 04

  And so geneticists have proposed that there must have been an early exit of Homo sapiens out of Africa, maybe 300,000, 400,000 years ago. There was some interbreeding with the Neanderthals. And yes, that put a little bit of Homo sapiens DNA into their genome, but also it replaced their own mitochondria and Y chromosome with a more Homo sapiens-like.

• 36:18Tristan Hughes?

  From a more basal Homo sapiens.

• 36:20Speaker 04

  Yes, these will be basal Homo sapiens getting out of Africa, meeting the Neanderthals, doing a bit of interbreeding, and changing, basically, they're replacing their mitochondria and Y chromosome with a more Homo sapiens-like pattern, which is why they have a younger divergence on mitochondria and Y from us than they do on the whole genome. So it's a complicated story, but the Epidima fossil might match that by showing us that there were indeed Homo sapiens in somewhere like Greece more than 200,000 years ago. And there's also evidence of earlier exits, which we can pick up in China and even Australia, because there are fossils in China that look sapiens-like, and in Southeast Asia that

• 37:04Speaker 04

  look sapiens-like, that are well over 60,000 years old. So I've mentioned, you know, the geneticists estimate the main exit was 60,000 years onwards that gave rise to populations outside of Africa today. But the fact that you've got fossils in China, in Sumatra, for example, in Laos, that are probably 70,000, 80,000 years old, means they predate that 60,000 exit. So there must have been earlier exits. And there's controversial evidence from Australia, too. So a site called Magyar Bébi II in Northern Australia, it's got a very deep sequence and, you know, beautifully stratified layers.

• 37:45Speaker 04

  And at about 65,000 years ago, on the dating from the sand deposits, there's a layer that has complex technology, a lot of use of pigments, and dated at 65,000, again, before the 60,000 exit supposedly. And we assume that's Homo sapiens because of the complexity of the behavior. Of course, some people say, well, how do we know? We don't have fossils. But that would suggest there was even an early sapiens arrival in Australia at least 65,000 years ago. So these earlier exits seem to have happened, but they didn't take hold in the same way. Either those populations died out, as seems to have happened in Europe after Epidima,

• 38:27Speaker 04

  or maybe they were swamped by the main dispersal that came out at 60,000. That ended up being in larger numbers, and it's actually overprinted any signal of those earlier populations that were there.

• 38:41Tristan Hughes?

  I love it, though, that these days are still being pushed back. Australia's a good example as well of that. Now, we've kind of explained all of that and looked at some discoveries and the importance of DNA. I hope you don't mind if we now kind of delve into the theories themselves in regards to out of Africa, because it's all well and good saying, oh, they spread out from here and went there and there and there. But what we actually mean by that, there's a lot of debate and lots of different theories, aren't there?

• 39:07Speaker 04

  Yes, I mean, you know, as I've already shown, my own views of out of Africa have changed, really, since those very early simple models. Things are more complicated. The evidence of interbreeding makes things more complicated. So yes, we could say that you've got the strict recent African origin model, and that's the model which the mitochondrial DNA seemed to suggest, that really, we can talk about almost a pure out of Africa. So Homo sapiens evolved in Africa pretty much entirely, came out of Africa and replaced completely all those other populations.

• 39:44Tristan Hughes?

  And that is just, and that is just the traditional, the plain, not simple, recent African origin.

• 39:48Speaker 04

  That's the model, if you like, the one extreme version of recent African origin.

• 39:56Speaker 04

  And I was always, I was never really wedded to that idea, although the mitochondria suggested it. I was always aware that there could have been a bit of interbreeding, but again, I thought that would be trivial in the big picture. So we were effectively 100% recent African origin, even though there might have been some interbreeding. Okay, then people like Gunther Breuer proposed a model called recent African origin and hybridization.

• 40:20Tristan Hughes?

  RAOH.

• 40:21Speaker 04

  Yeah, that's right. He proposed that from the end of the 70s into the 80s, and we worked together on publications and papers with that model as well. And so he argued that, yes, it was mostly a recent African origin, but there was some interbreeding on maybe a bigger scale than I was arguing, but we could therefore expect to find some fossils that might show evidence of Neanderthal features. But again, in the big picture, this would not be very important. And I think Gunther's model is probably closest to what we ended up with, with the interbreeding evidence. It's recent African origin and hybridization. And hybridization, because we're talking about interbreeding between, you know, what I regard as different species.

• 41:06Speaker 04

  So, you know, there will be these species coming together, even though they're evolutionary separate. And I mentioned really that this is something that we know happens quite commonly in mammals and birds. Someone estimated that 16% of bird species today have hybridization with neighboring species. So it's not as though this is a rare event. Genetic data shows it's actually a very common event. And so that seems to have happened in our ancestry. Then there was a model called the assimilation model. And this was proposed by people like Fred Smith and Eric Trinkhaus, again, in the, in the, in the late 70s and early 80s. And they were proposing that, yes, there was an African origin for Homo sapiens, but it was a much more gradual and diffuse process.

• 41:51Speaker 04

  So basically, Africa dominated the picture because of a larger population. So Africa, in a sense, was pumping out these genes of more derived Homo sapiens features, and these were then being assimilated in, by the populations outside of Africa. So Neanderthals were picking up those bits of DNA and becoming more sapiens-like. And over in the Far East, populations were picking up those sapiens-like genes that were coming out of Africa and were being picked up by populations there. So those populations outside of Africa would gradually transform with this mixing of DNA into Homo sapiens. So it's a kind of blend of an African origin and regional continuity. So you've got kind of both side by side.

• 42:36Speaker 04

  So it means Africa's important, but not as important as the recent African origin hybridization model or the real single origin model would propose.

• 42:46Tristan Hughes?

  That's, that's three.

• 42:47Speaker 04

  Third model.

• 42:47Tristan Hughes?

  That's three.

• 42:48Speaker 04

  And then we've got the classic multi-regional model, which argues that

• 42:54Speaker 04

  Basically, you've got ancestral populations for Homo sapiens all over the place. Where, where, everywhere that genus Homo lived and evolved, they evolved towards Homo sapiens. So the Neanderthals were evolving to Homo sapiens in Europe. We have populations in China evolving to Homo sapiens there. Populations in Java in Indonesia are evolving from what we would traditionally call Homo erectus into recent populations in Australasia. Um, and in Africa, of course, there's also a transition from early Homo populations towards Homo sapiens. So Homo sapiens evolves all over the world where ancient people lived.

• 43:34Speaker 04

  But there's not speciation, they're not going their separate ways because gene flow is keeping them together. So gene flow acts like a kind of glue, holding them together. Uh, populations in Africa are interbreeding with ones in Western Asia, who are then interbreeding with populations in Europe and over in the Far East. And so there's never enough genetic separation for speciation, and it's essentially the evolution of one species, Homo sapiens, over one and a half million years. Yeah.

• 44:03Tristan Hughes?

  Those are the four traditional.

• 44:04Speaker 04

  Yes, those are the four traditional models. Um, and there's also the braided stream model.

• 44:09Tristan Hughes?

  Yes, I've got this as well. So these are, these are newer models that are emerging.

• 44:12Speaker 04

  It's, yes, it's a newer name. I think essentially it's the multi-regional model really, under another name. So for me, it's very difficult to separate it from, well, probably the assimilation model and the, and the classic multi-regional model. Braided stream is really like both of those. So it's suggesting that you've got continuity over most of the inhabited world. It doesn't get in so much to those tricky issues of species, but it argues that essentially, um, there is no single place where Homo sapiens evolved. Uh, and what I've said is, well, if it is a braided stream, then it's a braided stream out of Africa. So the braided stream, the main, by far the main flow is coming from

• 44:54Speaker 04

  Africa. And yes, there are these subsidiary channels which pick up some DNA from these other populations, but Africa is still the dominant part of the story.

• 45:03Tristan Hughes?

  And lastly, the African population structure model.

• 45:08Speaker 04

  Yes. So I've been involved with people like Eleanor Sherry in developing that model. Um, and she's really developed this into, uh, what you can call a Pan-African model.

• 45:22Tristan Hughes?

  Okay.

• 45:22Speaker 04

  So the idea is that Homo sapiens did not evolve in one place. So, yeah, back in the seventies and eighties with fossils like Ommu Kibish, we were arguing, some of us, that East Africa was going to be very important in Homo sapiens origins, maybe the most important, maybe the single centre where it happened.

• 45:39Tristan Hughes?

  The birthplace.

• 45:40Speaker 04

  The birthplace of Homo sapiens would be in East Africa. Um, other people argue that it could be South Africa. So there are these different ideas about where Homo sapiens originated. Um, and the problem is that, of course, these models were built on where you had the best fossil evidence, um, which of course may not be where it was all happening. Uh, and people have compared this with, you know, the drunk guy who's looking for his car keys and, you know, it's nighttime and he's lost his car keys and he goes and looks under the street light because that's where the light is. But in fact, his car keys are somewhere else in the dark. So it could be that that's our situation, that of course, we look at the areas where there's the best evidence of Homo sapiens origins, and that

• 46:22Speaker 04

  could include Morocco now. But what Ellie argued, and some of the rest of us joined in on that, um, was that actually there were probably a number of parts of Africa that contributed to our origins. So Homo sapiens, early Homo sapiens populations were widespread in Africa. They were in Morocco, certainly. They were in Ethiopia, uh, they were in, uh, Central Africa, they were down in South Africa. And these populations, when they were separated by climate change, so for example, the spread of deserts at times may have pinned them back and separated them. And they went their own way in evolution, but at other times, uh, when climates improved and there was more rainfall, these populations spread into newly

• 47:03Speaker 04

  greened areas, met each other, exchanged genes, exchanged ideas. So we get a much more complex network, a braided stream, if you like, but just in Africa, where Homo sapiens is evolving as a composite of these different populations that finally come together, maybe a hundred thousand years ago, to become the Homo sapiens that then spreads across the whole world.

• 47:25Tristan Hughes?

  So the combining of these populations, I, I said, that seems to happen very late in the story of Homo sapiens then in their development and, uh, from what you were saying earlier.

• 47:32Speaker 04

  That's right. Yes. So this is a complex picture that goes on for hundreds of thousands of years, and we only get a kind of coalescence to, uh, a Homo sapiens pattern, both in anatomy and behaviour, that comes together, uh, maybe a hundred thousand years ago or so, uh, and then emerges from Africa and stays behind in Africa as well. Um, and there are some even more complex models which are kind of, you know, there as an undercurrent, that a number of geneticists are saying, well, even these models are too simple. And actually there is evidence that there's a very deep split in the evolution of Homo sapiens that might go back one and a half million years in Africa. Uh, and this is an astonishing

• 48:13Speaker 04

  model. It argues that there could have been, basically, there was one ancestral population, maybe one and a half million years ago in Africa. It then split into two distinct lineages, which then evolved alongside each other. One of them then gave rise to Neanderthals and Denisovans, and later on to the Homo sapiens that we find later on in, in, uh, Africa and then going out of Africa. But that second lineage is evolving alongside them for a million years. And maybe three hundred thousand years ago, it interbreeds with the Homo sapiens that are in Africa, and then produces the final push to make Homo sapiens as we know it today.

• 48:56Tristan Hughes?

  Anatomically modern.

• 48:57Speaker 04

  Anatomically modern Homo sapiens. And that population then disappears conveniently. So it's an incredible story, but there are several geneticists now arguing for these kinds of complex models. So if that's correct, it's even difficult to decide where, where Homo sapiens starts. Is it, is it one and a half million years ago? Is it when you get that interbreeding event maybe three hundred thousand years ago? Um, so this, these are newly emerging models and it's going to take a while for them to be integrated and also for the fossil evidence to be put together with them. But, you know, if they're correct, then it might bring something like, uh, our old friend Homo hydeobigensis back into the picture. So.

• 49:37Tristan Hughes?

  I mean, first of all, Chris, before we go into that, it, it sounds as if then like that, that, that theory then, us today, um, was it not basal, what's the word, um, derived or, or anatomically modern Homo sapien, we're, you know, from that converging, we're almost like a blend of different basal Homo sapien groups coming together, which I'm getting my head around now.

• 50:00Speaker 04

  Yeah. I mean, we're all having to get our head around it. And of course, these are models, they're, they're based, some of them on modern genetic data purely, some of them do incorporate ancient DNA. Um, but they're revolutionary models, of course, in the, the depth that they argue for our origins. And something like Homo hydeobigensis, so this is a replica of the skull from Cabwa, Broken Hill in Zambia.

• 50:23Tristan Hughes?

  Zambia, okay.

• 50:23Speaker 04

  And, um, we can now date it at about three hundred thousand years old. And it's, you know, uh, certainly a, not an anatomically modern human. We've got a massive brow ridge, a long, low skull, angled, angled at the back, rather like Homo erectus, quite a large brain though, there's a modern sized brain in there, but a big face. So this is part of what I've called Homo hydeobigensis. It's a species that was widespread. It was in Europe, it was in Africa, probably almost certainly in Asia as well. Um, and I used to argue that it was probably the common ancestor for us and Neanderthals. At that time, many people dated this skull at five hundred thousand years.

• 51:03Tristan Hughes?

  Right.

• 51:04Speaker 04

  And that seemed a reasonable date from which we could go to Homo sapiens and Neanderthals from something like this. That's what I used to think. But of course, as we found other fossils, as we've got younger dating for this fossil of three hundred thousand, I mean, that means it's about the same age as Jebel Houd, and it's much less sapiens like the Jebel Houd. So I then said, well, actually, I got that wrong. Hydeobigensis is not our common ancestor. It's a side branch that died out. But these basal deep split models that I'm talking about from the genetic data, um, they argue that there could have been a lineage alongside Homo sapiens in Africa for maybe a million years that then interbred with Homo sapiens about three hundred thousand years ago, and then

• 51:47Speaker 04

  disappeared. Well, Hydeobigensis might come into the picture, back into the picture as being that other lineage that coexisted with this evolving sapiens lineage, in which case even this could be part of our ancestry too.

• 52:01Tristan Hughes?

  I was about to ask, could this actually be a basal Homo sapien?

• 52:04Speaker 04

  Well, it doesn't, I mean, it doesn't look like Homo sapiens. So I would have trouble calling it a Homo sapiens. For me, it's a distinct species, but it would suggest that there was an interbreeding event which put in maybe 20% DNA.

• 52:16Tristan Hughes?

  Okay.

• 52:17Speaker 04

  Into the evolving Homo sapiens lineage. So a much higher level than has been talked about for, for the Neanderthals and Denisovans. So it would be a significant part of our ancestry. But again, in my view, we wouldn't have evolved from Hydeobigensis, but it would be part of our ancestry, an important part of our ancestry, if those models are correct. But I stress that they're newly emerging models and we're all looking at how they can work and that they need better testing, of course.

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• 54:40Tristan Hughes?

  Chris, I have to get you on every couple of years because it always seems that more complex things are coming out and more complex models.

• 54:45Speaker 04

  Yeah, I mean, of course, it's an exciting time with all these, all these different ideas coming through. But it's very difficult to give an overview, a simple overview, certainly, that, you know, the experts are confused now as much as everyone else is.

• 54:59Tristan Hughes?

  And also the fact that, like, I was getting my head around it, first of all, that there not being this idea of one birthplace, but then at the same time, is saying that there are several different birthplaces of Homo sapiens, also a bit misleading at the same time.

• 55:13Speaker 04

  Yes. I mean, Africa is still the dominant place in our, in our story. But of course, which parts of Africa? I mean, if, if this story is correct of these two deep, separate, separate lineages for a million years, we've got to ask ourselves, how could these lineages remain separate for a million years in somewhere like Africa? What was keeping them apart? Did they live in completely different areas? Or were they in some way different behaviorally that they didn't actually interbreed much until this last interbreeding phase at around 300,000?

• 55:47Tristan Hughes?

  We've covered a lot about the Homo sapiens story and how complicated it is now for, before the main exodus migration out of Africa itself. But if we focus on that, 60,000 years ago, how easy would it have been for Homo sapiens to leave Africa?

• 56:07Speaker 04

  Yeah, I mean, that's a good question, because we, we don't know the precise date of exit. We think it was a small group of people, or maybe a successive small groups of people, but close in time. And we don't know what the climatic conditions were at that time, because we don't have it precisely dated. So at times, we know that that region, northeast Africa and, and the Levant, at times it was relatively arid, at times it was, were watered with, with more rainfall. So we guess that it was probably a time when the climate improved, and that allowed Homo sapiens to move into the region. And of course, they would have been following their food. So if there was an expansion of grasslands,

• 56:51Speaker 04

  and even sort of woodlands, and an expansion of the animals that are feeding on that new, you know, expansion, then the humans are going to follow, because that's where their food is. So it may be that these people were just following their food in coming out of Africa. And, you know, of course, for them, well, Africa, you know, they didn't know they were leaving Africa, they were going into a new area. And that then was the beginning of that out-of-Africa expansion. There are some people who think that it might have been more a forced exit, that perhaps there was a deterioration of climate in northeast Africa, and these populations were pushed out.

• 57:27Tristan Hughes?

  And that would explain the larger numbers.

• 57:28Speaker 04

  Yeah, in, in trying to find a new area. So, yes, so we're not sure if it was push or pull. Were they pushed out into Western Asia? Or were they pulled out into Western Asia by improved conditions?

• 57:42Tristan Hughes?

  And in regards to the routes that they would have taken back then, should we just be thinking of Arabia, and the Levant, you know, Syria, Palestine, Israel today, that that area? Or could they potentially, those in Morocco at the Straits of Gibraltar, have made that short crossing to southern Spain? Well, Gibraltar and southern Spain today as well?

• 58:02Speaker 04

  Yeah. So in terms of the, the Western route via, you know, the Straits of Gibraltar, some people do believe that there were crossings, early crossings. So there are stone tools on an island off the coast of Morocco that look Neanderthal-like. But of course, we don't have the fossils to show Neanderthals were there. So most of the evidence, and this includes evidence of the, of the large mammals as well, suggests that there were not any early crossings across there of populations in either direction, from North Africa to Europe, or Europe to North Africa, and that those crossings came much later. You know, the waters there are actually quite dangerous. You've got very strong currents through there.

• 58:45Speaker 04

  And so, and of course, even if a small population got across, you know, it may not have survived. So the majority opinion is that we didn't have early crossings on the western side, and that, yes, it's over in northeast Africa. Some people think that there could have been crossings at the southern end of the Red Sea, where it's very narrow, and it would have been a crossing direct into Arabia.

• 59:08Tristan Hughes?

  And a more verdant Arabia.

• 59:09Speaker 04

  Yes. And, and Arabia at times has been much greener. So perhaps there were crossings down there. But again, majority opinion is that it would have been further north through the Sinai and into, you know, the main parts of Western Asia.

• 59:22Tristan Hughes?

  Okay, well, let's go to China, and let's go Peking Man, which is, I guess, this is, we can, we can use this skull a little bit for.

• 59:30Speaker 04

  Yes.

• 59:31Tristan Hughes?

  How does Peking Man, and explain what Peking Man is as well, if you don't mind. I've got a skull in front of me.

• 59:36Speaker 04

  Yes.

• 59:38Tristan Hughes?

  How this story potentially fits into the kind of, the recent African origin, or people used to think it did?

• 59:46Speaker 04

  Yeah. So this is an example, of course, of Homo erectus, one of the classic Homo erectus populations from China. So these finds began to be made at Jiugoudi En, near Beijing, in the late 1920s. And in the 1930s, there were controlled excavations there that recovered a wonderful suite of fossils that were similar to the ones known from Java, and what we now call Homo erectus. So these populations were in the Beijing area about 500,000 years ago. And for people who believed in regional continuity, the multi-regional model, these were going

• 1:00:26Speaker 04

  to be the ancestors of modern East Asian populations, for example, the modern Chinese. And people argue that you can see features in these fossils that come through to modern populations in East Asia today. For example, having a particular shape of the incisor teeth, a relative lack of wisdom teeth, third molars. These were features that were thought to be there in Peking Man, as these fossils became known, and that can be found in modern Chinese populations at a higher frequency. So that was the continuity idea. Of course, the recent Africanology would suggest that there is no continuity with erectus. There is continuity with Denisovans, who are a lineage that we think evolved alongside erectus.

• 1:01:10Speaker 04

  So in China, we had the continuation of Homo erectus down to maybe 300,000 or 400,000 years ago. So there for over a million years, but also alongside them, we've got the evolution of Homo longi, dragon man, and we've got this replica over there. That green-colored replica is, is the halving cranium, which we think is, so it's the type specimen of Homo longi, dragon man, but also pretty certainly a Denisovan. So that lineage was in China as well, evolving. And the erectus lineage died out. The Denisovans continued for much longer, interbred with Homo sapiens, and then they died out too.

• 1:01:51Tristan Hughes?

  So it's this idea that, you know, once thought that this meant that, kind of contrasted with the recent African origin theory, but more recently, with the discovery of the Denisovans and so on, actually, this has been largely debunked now, do you think then?

• 1:02:07Speaker 04

  Well, there are some people in China who are still wedded to the idea that Peking Man fossils are important in the ancestry of, of modern Chinese people. So, you know, there are some political factors in there as well, which are influencing those views. And of course, it's, it's possible there is a little bit of DNA even, because there is evidence that there was archaic intergression from a very early population into the Denisovans. So possibly erectus, well, in fact, almost certainly, there's evidence that erectus interbred with Denisovans, and then Denisovans interbred with Homo sapiens. So there could be some transmission via the Denisovans of erectus DNA into Homo sapiens today in the Far East. So there could even be a little bit.

• 1:02:52Tristan Hughes?

  Fair enough.

• 1:02:53Speaker 04

  Never say never.

• 1:02:54Tristan Hughes?

  Recent Asian origin, recent African, it's, it's, it's so interesting, I guess.

• 1:02:58Speaker 04

  But it's going to be a very small amount of DNA, but it could be there at a very small level.

• 1:03:03Tristan Hughes?

  And Chris, like, what do you think is the best one-sentence answer to Homo sapiens origins today?

• 1:03:12Speaker 04

  I would say that we are mostly out of Africa.

• 1:03:15Tristan Hughes?

  Mostly out of Africa.

• 1:03:16Speaker 04

  That summarizes it for me.

• 1:03:17Tristan Hughes?

  I think that's quite nice, isn't it as well? You brilliantly detailed all those that the complicated, how it's getting more and more complicated, the thinking about our story before we leave Africa, multiple birth places, converging of populations to form anatomically modern Homo sapiens. And new discoveries coming out, it seems like there's still so much we don't know and why it's still so exciting, but bound to get even more complicated in the years ahead.

• 1:03:44Speaker 04

  Absolutely. I mean, just think, since I did my PhD, just how much has happened. It's incredible how much our knowledge has grown. And yes, in some ways it gets more complicated and other ways it gets simpler because along the way we can dispense with the incorrect ideas, you know, as we have new dating, we can dispense with the confusion that was created by bad dating, where we get fossils that have been wrongly interpreted, we can get rid of that confusion. So yes, in some ways it's a more complicated story. I would say it's a richer story. It's a more honest story of our origins. And I think what it shows us is that actually Homo sapiens origins, in my view, is not something special.

• 1:04:25Speaker 04

  If we had this degree of information about the evolution of, let's say, lions or pandas or hyenas, they would be similarly rich if we ever have the evidence of gorilla and chimpanzee evolution, which we mostly lack. They would have their own rich stories to tell as well. So I think this is showing us the way forward, that, you know, when you get more data, yes, it's a complex story, it's a richer story. And it isn't just our story. All of these other species had their own wonderful origin stories to tell and we shouldn't forget them. And of course, that's true for the Neanderthals, for the Denisovans, for Hyderbregensis, all of them have their own rich evolutionary history that we're only beginning to tell.

• 1:05:08Tristan Hughes?

  Chris, you are one of, if not the, leading expert on human evolution and early Homo sapiens and the developing story in the Anstels. We'll have to get you back on as well in the future. It just goes to me to say thank you so much for taking the time to come back on the show.

• 1:05:21Speaker 04

  It's been a pleasure again.

• 1:05:27Tristan Hughes?

  Thanks so much for joining us on The Ancients today. I hope you enjoyed the episode. And if you are loving The Ancients, then why not become a History Hit subscriber? As a subscriber, you will have access to hundreds of hours of original documentaries with a new release every week, plus early access and ad-free podcasts. You can sign up at historyhit.com/subscribe. See you in the next episode.

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• 1:06:10Speaker 03

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• 1:06:29Speaker 03

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