it's always hope it's an embarrassment to give a talk with the Wellcome Trust because I actually have virtually no biology qualifications whatsoever having started life as a historian and and I think that's that you know that's an important journey because in the end we are trying to reconstruct history in this what has happened and I have had to learn the hard way is that the way in which we try and learn that history has been transformed completely by the genomic data that now I think it's fair to say and I say it with some regret drives the subject in which we work and I think every paleoanthropologist has to respond to that and it drives it very fast and it's very slightly daunting to give the first talk of a session on the other hand it gets it out of the way however what I'm pretty sure of that by the end of the first day something like 20% of what I say will be wrong by the end of the second day something like 50% to be wrong and I'll end the conference hoping that's something I've said at the beginning still holds true but we'll wait and see whether that is actually going to be the case now what I want to do in this is to talk about really a take on the question of how much the models with which we work on modern human evolution have changed and for that we have to go back to deep prehistory 1987 the annus mirabilis of human evolutionary genetics when can it al we all know can a tell and the Christmas tree publication came out and introduced us to the idea that humans evolved in Africa with a relatively recent origin and a pointer a pointer oh you stole it thank you and the idea of a recent origin and the beginnings of this thing we all call the Out of Africa model I know there are some other names for it but we'll stick with the Out of Africa model as a paleoanthropologist I feel duty-bound to say that actually Out of Africa was there before and we can go back this paper this this book by WW Howells one of the great figures of anthropology and this book the origins of modern humans both of which never quite as directly obviously intimated that we should be looking in Africa for the evolution of modern humans and so the idea was around to some extent as in so often in science when Wilson natal published their paper it fell on receptive ears people who were keen to grasp this as a new way of thinking about things and I just say in passing but not say too many things in passing I'll run out of time but in passing just that the Revolution was not just the Out of Africa but also the focus on modern human evolution because the 60s and 70s were dominated by early human or hominid evolution of Pliocene Pleistocene of Africa so it really was a sea change in how we thought about things now the mitochondrial DNA when it came out was just one part of the story what it showed was the low level of human diversity or mitochondrial diversity but it was much higher in Africa and the inference of an African origin and that with remember here entirely sub-saharan Africans on this branch suggesting that modern humans evolved in Africa relatively recently from a small population and then dispersed around the world and this became the Out of Africa package and of course it's not just a package in terms of mitochondrial genetic diversity what came with it was the idea of a single and one major dispersal across Eurasia the spread of humans out that that involved when they came out when modern humans came out there was no admixture they replaced the replaced the archaic hominins and to try not to say there are two models of hominid human evolution but that's the other one of course the mighty regional one it was suggesting complete replacement and of course therefore extinction of archaic hominins such of Neanderthals and in addition it suggested there was a correlation between anatomical and hey modernity this is where the idea of modern humans really came on to be discussed widely and the idea that somewhere after that mitochondrial Eve dispersed out this new species had all the traits anatomical brain size brain organization technology culture anything else you want to throw in there and this this this was an abrupt change in behavior and what this became of course was the human Revolution very very popular in the the 1987 CA of course the the Bellas and stringer vol the human evolution and the idea that this package produced humans in a sense with one with one event origins dispersals replacement and a sort of cultural revolution modern humans evolved and it's getting a very abrupt model and so with that in mind we all know we're all working in this field we know that there have been major changes in in in the evidence for this over the past thirty years doesn't it since since then and we need to try and think a little bit about it so I want to say oh we should we now be thinking of a completely different model should we be abandoning Out of Africa or jazz it just a matter of tinkering in case you're wondering what this symbol is you can work out that the spanner is to do with tinkering the axes is an old philosophical problem this is my grandfather's axe he my father changed the handle and I changed the head to which philosophers you can think about this instead of my talk now is it still my grandfather's axe and so the question is has so much changed in the model that we should really start to think in different ways about it and that's the the journey I want to take us on in the course of the next 50 minutes or so now of course I'm not the first person to start to think that maybe there's more to the Out of Africa model than the human Revolution and I put here just some of the the papers that there have been over the last few years in fact going back right to the beginning I found I forgot that we matter and I published this paper here 1992 so that's just a few years out of Africa or be calling it beyond out of Africa a reassessment reassessing the origins of Homo sapiens so I think we were first on the blocks they hang on there's more to this and I should at that point we talked about martyrs say that you see my name here on that on the on the lecture however many many of the ideas that I'll be talking about are things that as you probably all know we've worked on together over many years so what are we going to do I'm going to do three things in the first instance or for most of this talk firstly I want to talk about the deeper age for the last common ancestor of modern humans and archaic hominins and what this means I want to talk about the increasing evidence what I shall call demographic complexity the admixture and dispersals and thirdly the the increasing evidence that we're dealing with a synchronic and mosaic evolution and the way in which this evolves so I want to run through some ideas about those three topics so now I'll finish up talking a little bit about some aspects to do with the evolutionary processes underlying it you might even get a bit of climate in there just to sort of make the title make sense so if we go back just to think back to 87 the Out of Africa model predicted a relatively recent common ancestor and although the numbers were vague people talked in terms of one hundred and fifty thousand three hundred thousand for the branching of Neanderthals and modern humans and this was a very recent origin of the paleontologists at the time tended to think if they thought at all about this as the divergence as a single divergence tended to see a rather older date so people like Kunta Brauer were talking here about dates of six seven eight hundred thousand there's quite a revolutionary change in terms of the recency of human evolution and since that time there have been a large number of new estimates of the age of the last common ancestor with modern humans and just sort of picked on a little bit ago this is one that Martha and I did back in 1997 based on archaeological evidence and we thought somewhere up to 350,000 years was the sort of age this was the neanderthal genome paper sort of range from 700 thousand three hundred and seven thousand I won't go through all of these it's an archaeological one georgette who bland on the paleontological evidence thinking in terms of about six hundred thousand and recent work by Mooney O'Meara's on la using a virtual ancestor construction against against seven hundred thousand so some are younger some are older but broadly speaking they're all well beyond the original estimates that came out in the human Revolution model so the first thing we have to take onboard is that human evolution modern human evolution takes longer than we thought it did now that could just be well you know just longer time but we can also think about what that means in in terms of the processes in the event however in doing so we also have to think a little bit about what exactly do we mean by the last common ancestor and I've and and you know I'm not going to talk about last common ancestors with chimpanzees but the last common ancestor in the discussions with modern humans of course originally really meant modern humans and Neanderthals as that as the divergence from trying to estimate that age now we know following the discovery of the Denisovan genome that Neanderthals and Denisovans represents this two clades so there was never a last common ancestor with the and atolls there was the last common ancestor with the common ancestor of that archaic lineage the eurasian lineage of archaic hominids and so we would be thinking here of that ancestral point however the one that people forget about is this one which i think is the important one so we've got some divergence here of modern humans of the the african leading to modern humans and the one leading to Neanderthals and Denisovans here but of course this when this lineage parted company these lineages parted company in africa presumably it was not a modern human there were archaic africans and those archaic africans are likely to share many characteristics here and so this is perhaps the divergence date that we should really be thinking about in terms of the shift from modern humans and when when does this occur well it's very hard to say and this is the point at which I make the usual paleontological plea that the fossil record is very sparse and it's very sparse in terms of the the Middle Pleistocene the late Middle Pleistocene of Africa and that there are very few however Georgia who blames recent republication of the Java Leah home with new dates and new morphologies has a creature which is very nearly a modern human anatomically and of course we can compare that with the modern humans that we pick up that's not actually over cubish but anyway the omo kibish specimens 190 190,000 maybe it is over kiddush it is couldn't see from this angle 190,000 years ago so we can sort of put this in this last common ancestor here in the three hundred to two hundred thousand year sort of range anatomically speaking oh and we can think a little bit about what does that mean genomic at all cause the sad answer is we can say very little about it the now why does this why does this matter why do we really care well the care we care because when we have to confess I'm not terribly interested in the genes I'm interested in what in what the genes do to produce a phenotype and it's the phenotype that goes out there and adapts to the environment Michael referred to my ecological interest it's phenotypes that adapt that live that survive that undergo natural selection so what is the phenotype like so of course we want to know what was the phenotype like of humans and as I said there are relatively few fossils and what the genetics can do is they can by giving us last common ancestral dates they can rule out certain possible ancestral States they can say well you know the split is so early it cannot be anything it's all that split is so late it can't be something else so we can use the relationship there to try and tell us something and this is where the now the the where we need better resolution is of course if we have different estimates for differently last common ancestors that I've just put three random ones in here at 400 300 and 600 this would be the sort of early splits here then amongst these fossils here we have a whole diversity and different last common ancestor dates would provide us with different ancestral possible ancestral states and we would reconstruct the past differently now that's true of both of the phenotype there are developments it's not so I think this is a challenge for the geneticists to come up with more precise dates of what exactly mean particularly within the African lineages because that's where the action is taking place that's where modern humans are evolving in the last half million years but also the new technologies that are appearing that allow us to allow us to and I don't do any of this sort of stuff but matheran and irelia in their paper this year showing you could you can start to reconstruct using scanning technologies using virtual reconstructions to be able to reconstruct them the potential ancestors so that we can create new fossils we can create models of what these phenotypes should be and then start to compare them with the fossil record this is not saying what they're like but they give us hypotheses I won't read through all this you read them all you've gone through you've read all through already but it gives us some idea of where and when and what to look for and I think it's critical and again I emphasize this is an African problem now I've talked about the phenotype and the morphology in all this but of course it's not just the morphology you know I used to try and persuade my students that you know they had to know every lump and bump on the skull of it on a human skull because that's what the essence of being human was and they quite rightly loved sort of went to sleep and said know what being human about is our behavior its language its culture it's symbolic behaviors these things that are critical so if we move away from thinking anatomical modernity and think just about the evolution of human behavior we can say we also want to be able to reconstruct that the ancestral states of that at the time of the last common ancestor be it with the Eurasian lineage or being with this hypothetical African one so here I've just plotted very crudely what we do know about some of these things that have markers of modernity and I'm going to Park the question of what exactly modernity is so this is modern humans and back here at 300,000 years ago they're hafting technology of hafting technology becomes important they're making blades mode 3 technologies of present use of oka presumably for some sort of decoration of people's skins shells there's some functional uses are too but we'll ignore that for the moment ritual behaviors are dead the hatter skull 160,000 year old very early modern human there's a baby skull which has polish on it on the skull and that polish probably came from it being carried around for quite a long time after the creature died so here we've got you know some but i now learned it's called thanatology you can look it up on google while i'm talking the the the the processing of the dead in a particular way we see the marine exploitation and so on i'm not going to go through all these as as being clear markers of modern human behavior then we can also do the same and look across at the poor benighted Neanderthals and watch them doing absolutely nothing while we evolve our modern behavior and so i've plotted the same things here and they have hafting they use ok that's ok there's this amazing site in france where their cave and remember the name that big be care Bruni quelle Bruna quelle where there's a this circle of clearly ritually placed things deep inside a cave and of course they've got marine exploitation some of it's a bit later in terms of date but it really doesn't matter there's a this is being argued about to death these cave to cave art stuff but anyway and we'll take it for granted so suddenly we've got a very different pattern so if we then say well let's put the two together tell me the difference between the eurasian lineage of Neanderthals and the modern human lineage of africans and and we can say well that's important and it's important it's important for a couple of reasons one reason the one the one empirically we have to think about is i come back to ancestral states if we want to reconstruct the ancestral state if it turns out all these things here are shared across as a good playtest we immediately the simplest explanation is that they were present in the last common ancestor and that puts them into that sort of framework and the second is is this is more to do with the Anatol extinction so when modern humans come into europe and these guys go extinct than the and ourselves the Denisovans okay we'll talk about admixture in a minute they go extinct we've tended to assume they go extinct because they were so different from us and I think a much more interesting and ecologically sound model is to say they went extinct because they were so similar to us it doesn't mean there were no differences but we have to think much more comparatively about this whole problem so I think one of the challenges that should is to here's a table which I haven't filled in so I'm the slightest idea how to fill it in but lots of you can start to think how you do it is this in a sense is our problem we've got modern humans and their African rkx here as the key down here and Denisovans Neanderthals and we're trying to construct in fact four separate and ancestral States hang on one two three four five six well we have five the ancestral States and the thing is we want to be able to fill in here what are these conditions and then we can start to work out about the evolution of humans across this longer chronology much longer chronology than Wilson had in mind when he published Wilson and Rebecca cannon marks don't we published the 87 paper and Chris and Paul were talking about the human Revolution so it's a bit of a game-changer in my view and of course it raises the whole question I've assumed that if things are shared their shared because their ancestral okay it's a pleasee amorphic trait it's a simple easier more thing that these features are the common answers because that isn't necessarily the case you know bats and birds fly but it's not there's never an ancestral trait and and so we have to think how something like mode 3 technologies and indeed brain size might have evolved convergently in these two lineages which produces you with an entirely different modeling saying two lineages separated have become more and more similar over time well I'm not I have my preference which I'm not going to disclose today as to which of those models is correct but we have to take that on as an empirical challenge and think of ways in which we can resolve as in any evolutionary issue where convergence is a stake and work out ways of resolving it so what are the evolutionary implications of this there are just two I want to emphasize of this deeper as deep African roots that I think are important the first one is here what I've done is just to plot here the longevity of all the hominin taxa such as how a first appearance date and last appearance data for all the you know Australopithecus this and Australopithecus that from the early period and this is just a fairly typical curve curve you'd find if you plotted any lineage and I just put on here where modern humans as a as an anatomical species appears and we're back bang in the middle in terms of the length in which that lineage you take the African lineage this sort of six hundred thousand year date then we come one of the longer lineages that persist so again I emphasize the importance of bringing in a comparative approach they well what's happening is it this is typical evolutionary processes going on so that's my brief consideration of deep deep African roots and how we have to think about that the the this extended chronology retreat which we didn't think I've just put this up here for you to read I won't go through all of them other than emphasizing the nature of the common ancestor is important we just have to work out which common ancestor we're talking about we have to raise the questions of what it is what is the significance of so many shared features with between African and Eurasian hominins and what is derived what is what is convergent and and and I would ask people the geneticists to go out and find us this creature here the African last common ancestor the archaic so of course it's not going to be simple and it's not going to be simple for the reason that I'll come to in a minute so coming to that how is this a change of you know is this a grandfather's axle change the handle or is this just tinkering I again I think I'll leave it to you to think it's - the chronology is the actual length of time takes place does make us think very differently about the processes by which modern humans evolved the revolutionary model I don't think is appropriate in this stage at this stage now the the question about exactly what the last common ancestor is like he's made a bit more complicated but the next little section that I want to talk about this demographic complexity when can it L published the glorious mitochondrial DNA it emerged out of it that there was no admixture we did not share any mitochondria with Neanderthals when the ancient DNA material came out and so the suggestion was no admixture replacement extinction and that of course is something that has been eroded extensively in in the last I went the first admixture stuff just 5-10 years it's been suddenly you know it's all the rage to find and I'm not going to go through many many models in our arrows joining up branches as an evolutionary biologist I hate arrows joining up branches reticulation because it complicates life but quite clearly it's all going on there here's a very beautiful example guy Jacobs at AU published earlier this year and it's beautiful because it shows two things one is that the admixture is there are three add mixtures here the Denisovans and pap ones but there are three add mixtures not just with three different platform populations or different elements in the platform population but three different Denisovan populations so the dynamics of what is going on across this time it's not you know I'd draw trees with these lot big branches these big trunks of Eurasians and of course it wasn't like that they clearly were themselves diverging and changing over time so that that becomes so this complexity here and I'm not good you know we can spend a lot of time trying to work out how many admixture events the events there are but in the end this is as good a model of human evolution as possible this is thanks to Luca Pagani at allied I've modified their diagram I think it's such a beautiful way of presenting you know this is the London underground map of the human human evolutionary history and you take the wrong branch and you're all over the place but it just stresses that the you know various points admixture is taking place and of course this is only part of it because of course the closer you come to the present the more this is going on within our species and it becomes a critical and important part so what does this admixture mean for the Out of Africa model and the way we're thinking about it so it's the first days is what I passed very briefly on this scale my I mean someone can correct me if I'm wrong I mean the way I read this is that there are a number of events which suggests to me that the in the admixture was not a continuously Asian thing it was a patchy happened here happened there happened at this time not at that time with this population with that population so if we were sampling that let us say of a mythical period I was 35,000 years ago or something we'd find a very patchy distribution of genetics and then over time because everybody moves around and modern humans add makes even more it smoothes out that distribution so the scale of our understanding again make sure it's going to vary where you're looking in that quilt the patchwork quilt of these admixture events I'm not even say anything about this because I don't have time but just to point out there are there are adaptive consequences and there are many things to do with the there are there are many things to do with the the actual phenotypes you know now that we can identify things there are some areas where it's quite clear there are major differences between the avatars and modern humans where where we know things have been selected against and disappeared from the human genome particularly associated with with reproduction and some suggestion with neural things too so maybe we weren't that identical but there are also been some suggestions of a more positive selection for Neanderthal features maintaining them in the population at higher levels than you'd expect given the initial sort of founder effect nature of the admixture that went on so there are consequences of admixture to do with the actual phenotype defined broadly and the patient's just to bear in mind but as I am totally incompetent to talk about them I don't know now the other thing of course important is admixture and species boundaries I mean I you know I was brought up in the days of homo sapiens covered pretty much everything from erectus to today you know this glorious archaic sapiens and and so on and I I was with great relief Homo sapiens became anatomically modern humans it was clear hominid and the tolerances with all the admixture one can perhaps say it's time to abandon that go back to the very generalized Homo sapiens because that mixture but I would just caution against this so you can turn your eyes away at some of these things if you want but this is this is this shouldn't happen in biology the tiger and a lion they produce ocular muscle remind me I can't remember like isn't tiger on what they call ligers and Tai grens and things and their admixture and there's two things I want to make a so here's lions and here's Tigers Tigers are not the sister species of lions leopards are okay so in other words lions and tigers are hybridizing outside their own family outside their own lineage which is probably pretty weird and and and so this I think this is about a five six million year split something like that that's a very that's much much greater than anything we have doing the end cells and they produce really weird phenotypes I mean look at the size of this creature here and they're unpredictable so and different ones and their sex related whether the lion is the father or the tiger is the father and so on and it's highly variable so there are impacts now I'm not going to go and suggest because this is happening these are these are these are further these are these hybrids can be fertile I'm not going to suggest that lions and tigers and leopards are all one species I will carry on treating in a separate species I think we should just use it as a recognition that species boundaries are not necessarily usefully defined in terms of process by ernst mares definition of what a species is a biological species concept it's too static it's too much at the end of the process for us to worry about so the second aspect of demographic complexity if there's so much complexity in is is that it's it's dispersals it's the fact that different populations are moving around there's dispersed was going on so remember the the Out of Africa one out for the model originally suggested one one big dispersal Kim you know swept the world kind of a major change and this paper by BAE at our camera you know nepeta in particular and multiple dispersal model perhaps the beginning at the advent of the late Pliocene needs to be examined more closely I had to say I not sure I treated this with a bit of caution because we wrote a paper in 1994 called multiple dispersals and modern human origins and another one in 98 really emphasizing that there was more and more evidence for multiple dispersals now the genetic evidence has gone backwards and forwards on this and depending on what day of the week it is you know either it's one dispersal or two or three or four and they think it is now clearly settling down to being a slightly more complex one of course it depends at what scale if you're just talking out of africa or versus dispersals within Africa within Eurasia once they come out I think the evidence now is quite clear that if you take this whole lineage here this evidence across the hub this is 600,000 years if you can't see it and this is the climatic wobble warm to the right coal to the left and we can see a whole series of ones for the African lineage coming into Eurasia this is this ancient DNA suggestion there was the input of African genome genes into the early Neanderthals around about 300,000 from the llena group app edema catarina Hvar tease discovery of a fossil modern human in in greece two hundred and ten thousand years ago and they should it shouldn't be there according to all the models we've got miss lyre in in israel 150,000 ish time all the the van tine expansions in very nice at upstage 520,000 dish the new evidence from east asia of possibly eighty thousand plus for further expansions and wool Asya I think Kris Clarkson's here he can he can decide that I got the arrow in the right place for Australia oh yeah and I was early and then of course the big one you know the one we all know about the big Eurasian expansions taking place across this time so multiple dispersals I think there is clear evidence now of course that provides us with a much better basis for understanding the complex pattern that underground map the London Underground map of all those interactions because each one would have had had brought a different genotype and phenotype and behaviour to this pattern now that's just the tip of the iceberg because once you get into the late pleistocene some we're talking after 30,000 and into the Holocene people are just on the move I mean it's just one great big merry-go-round of populations moving moving in response to the onset of the last places glacial maximum as it gets colder and nasty movements prompted by lowered sea levels allowing greater access to certain areas movements prompted just because somebody's got a better way of killing a mammoth and such as the expansion of the gravettian populations around about 30,000 bit older than 30,000 years ago and and causing replacements within the Upper Paleolithic or partial replacements so these dispersals are are multiple and they're very significant in terms of this this this complexity we should perhaps think something about and make certain just think about dispersals and their outcomes from an ecological point of view and I just want to suggest we you know we this little matrix will help to to think think about these multiple dispersals and the multiple outcomes so if you just think there's an indigenous taxon which in our case is if we talk about Eurasia is going to be Africans and there's a dispersing one so as I say Africans this is going to be Europeans erosions and this will be dispersing on so they can be anything you want doesn't matter and then the indigenous one can survive be admixed or go extinct okay we can be more sophisticated about that but remember I'm a paleontologist the and we can say the same here then we can just think about the outcomes so fully admixed is full hybridization you know you have two populations they come together they have a party and and everything is full hybridization you can get unsuccessful dispersals taking place in extinction and I think we should be thinking about all our dispersals in terms of where do they fit into this range of possibilities this range of of models so we can start I think the the big ones the Eurasian expansions in this sort of time range there is admixture but it's basically the assimilation of the native population into the expanding one because we don't see major it's not as if the and atolls dominate the genome and so it's they're absorbing and then it's not a wipe out it's not quite out here anymore the replacement but we come to other ones did anything happen no okay we can have other ones and perhaps epidemia here 210,000 well maybe the modern humans came in and they died out you know it doesn't mean they're there it was just an early early my supervisor graduate supervisor who's been in the war always used to talk about early modern humans as sending out reconnaissance parties as we're a military metaphor so there was a reconnaissance party in his term for modern humans in Eurasia but anyway it's an early dispersal which perhaps became extinct and then on the other hand there could be other other situations where a simulation of dispersing population so the presence of these genes African genes in the early Neanderthals might be that the modern humans came in Africans came in but then they just got absorbed into that population in some way or other no this is just the genes you can play this game with phenotypes and behaviors as well so this demographic complexity combined with the extra time we now have on our hands is a transformation in the model we don't know whether it's kind of this is just Leakey gene flow or genuine dispersals and that's a major problem because I think it should estes use dispersals of migration in a very different way from ecologist it's multiple dispersals but there are multiple types of dispersals and there are different outcomes and these are going to be the the challenge to try and work out what is going on is this uh is this now the you know we now changed the handle and the head in in this model well I think certainly it's a bit of a push when the emphasis is on replacement it it's quite clear that's no longer enough of a model that we've got so many things going on so we might be moving more in that direction because I'm a bit of a gradualist at heart I still keep the spanner going I like to tinker around with things so let the third segment of this is is this question of what I'm calling a sick a synchronic and mosaic evolution the Out of Africa package you remember was a was revolutionary human revolution with everything being transformed in one time and many people I mean I don't if Chris is here Christian is here but you know he would now I think have moved very much away from that revolutionary model ii think there's a much more continuous process a longer one so the chronology is longer chronology and this comes out of all the things I've been talking about so far the dispersals the admixture there's just so much going on over such a long period of time and I think that rules out that this this upper paleolithic there was this some idea of a human revolution they partly of course the human revolution was was really trying to apply a European model the middle to upper paleolithic transition to an African problem because actually what it confused the very contrast between the middle and the upper paleolithic in Europe confused an evolutionary event what was actually a replaced a replacement event and the two are very different so I think the important thing is to get away from now we know you might do you know we know that that European record itself has become much more complex and I'm not going to talk about this because I don't know enough about it the European record here that they say the appearance of the upper Palaeolithic the so-called only thing he's not a synchronous thing there's all sorts of weird things going on it's no longer just the organization moving in you've got you've got a number of different events spatially and temporally variable so that that is very different but of course the African evidence is the key and this is the sort of point I want to emphasize is if you're looking for a big framework in which to look at the evolution of modern humans it is the African little Stone Age it is the African Middle Stone Age which both the archaic hominins modern humans and indeed the in terms of technology the early eurasian lineages were all using what do I mean I realize that most people just say what do I mean by the middle Stone Age it comes between the early and the later is one thing but it also so in in the in the lower Stone Age in the early Stone Age they were making hand axes these nice beautifully shaped symmetrical objects we it's beautiful in some ways but it's relatively simple you just go around and you if you're skillful you could make this shape by just fooling around and knocking the bits off and it gets closer and closer to the shape this is really cool because what they're doing here is they're taking this core and they're shaping the core and Chris Clarkson will give a demonstration later on maybe he's really good at this they're shaping the core so that when you want the flake which is this beautiful point here you just have to do it one one hit and off comes the flake already the shape you want it's a complete transformation complete transformation in the way individuals populations are making are using technology you know we can argue about the but what's cognitively changed or ecologically changed in driving this but it's a it's a big one and and what we can say is that it's certainly now with Jabalia hood analogous ID this is happening by three hundred thousand years ago there's a slightly dubious date and it goes back nearly half a million years so but let's be conservative and say in this phase here which of course is about the time we see the modern human phenotype of hearing as well so this middle stone age is the critical it again it's part of this moment and if you think the early discussions about of Africa were focused on what was happening archaeologically forty thousand years ago we actually should be looking what was having three hundred thousand years ago so this is the kind of pulling it all together say well if we think of what we've been talking about we've got 800,000 years of time to play with we broadly speaking have an African lineage and we have a Eurasian lineage the African the Eurasian lean lineage divides into Denisovans and Neanderthals and who knows who else might be out there that we need to think of and the Denisovans and the an tells themselves divided up when I put a little variation the African lineage we've got the modern here we don't very little about we're yielding a divergence of Africans the African and our cakes and of course we have all this admixture and then plotted on to here I've just put is red is a behavioral change which I mean archaeological archaeological evidence behavioral changes Green is morphological sets of the Anatol appearance of anatomically modern humans and shifts going on in morphology blue is dispersals I would now add a lot more to this diagram probably but we can fill it in as we as we feel for it and then extinction is when things disappear nice good black so across this and this is a minimalist view of the complexity of the last half million years to a million years in terms of evolution and then the our greens are the add mixtures that are taking place so it just means that that's the framework it's a much more population-based and multiple Fastenal t faceted approach that we have to think about for this so if we look at those three things we end up with with this idea of of what I'm going to call the extended out of Africa we don't need a new name or anything but and its really emphasizes the multiple events across different domains in the phenotype the genotype and what I'm calling the extended phenotype as behavior it involves mosaic evolution not synchronic horizon a synchronic horizon have changed across these and it involves complex - not complex demography driven by dispersals and biogeography so I think that's where we should be thinking now if I have about five more minutes - 15 minutes I haven't got 15 minutes left to say okay so if I have got time which it seems I do what I want to do is to finish off by saying okay let's step a little back from this and and stop thinking this solely in terms of the evolution of modern humans that's put on our evolutionary biology hats and think well what actually is driving evolution in general and so I want to talk about two or three things here about about there starting with phenotypes genotypes and and so on so this is my little cartoon that summarizes all evolutionary potential and and you can say well evolutionary change takes place because you get a change in the genome and an isolation of populations and that you get the the Claddagh genesis the speciation taking place through a la patrie or whatever new context produces a new phenotype and that new phenotype invents an a new new new behavior however you could have a model in which you get a new phenotype evolving they think up a new tool and then that gives all sorts of opportunities they spread their allopatric li separate and the genes and the population dynamics follow-on from that or we can come down here as a lots possibly say perhaps it starts with the behavior your change in behavior and this this produces you can put this in whatever or do you want this produces either new behaviors with new geographical distributions and so a la patrie and separation and and competition between groups and a new phenotype now this this at this last of these is actually referred to generally a lot of people photos the Baldwin effect like my former colleague look like Pat Bateson called it the adaptability Drive and the idea is that actually evolutionary change is more likely to start behaviors so I always think use the example of bipedalism some ape ends up trying to be bipedal because it's got a walk between trees and those who can do it better who have that behavior rather better end up because you know those individuals who can do it slightly better because they've got the phenotype so the behavior drives the phenotype so it goes in that direction and I think when we go back we went back to that diagram I had we want to start to look at are the where what is the relationship between the behavioral changes we're seeing and the anatomical changes and can we see use the genes in any way to map out what is going on as a behavioral ecologist at heart I tend to think it's the behaviors change first and the morphologies are following on from that but I could be completely wrong we have no our primary reason for thinking it might be one rather than the other but I think that is a big challenge the other thing we need to think about is species and speciation I've talked about species in terms of species boundaries and admixture and part of the problem comes because we think of speciation has an event we've all read our books on the speciation event and what Martin and I have been working on for many years now is that is to rethink a bit the speciation process now there are numerous definitions of species numerous ways of thinking about species and and what we tried to do here is to say well actually all the different species concepts we have Simpsons evolutionary species species is just something evolving independently we have Cray Kraft and Eldridge in people's phylogenetic one a species is something that has something different about it it has Apple more fees to Patterson species mate recognition it's a different species if it has sex in a different way he didn't put it quite like that but in other words it's the it's the sexual selection of submits the reproductive selection motors leave and Valens model and ecological species it's a new species when it's doing something different and he doesn't care about what it looks like anything is it's ecologically different it's a separate species and then we have the you know the mummy and daddy are the more Ernst Mayer's biological species it's a species when it's genetically isolated when it can't interbreed and what what I think what we want to try and think about is that these are not alternatives they are just thresholds on the way of speciation to you you know a la patrie separating out geographical separation is that the basis at all as that happens you get phenotypic or behavioral differences establishment of a specific mating different mating or ecological differences come in and only at the very end of this process do you get genetic separation so part of the argument here is that actually by the time you get true this is talk about mammals here I should emphasize all sorts of other things go on with different different species different you want to get into the weird and wonderful world of insects and plants you can forget about that that they in a way the really exciting evolutionary biology is taking place prior to that and so when we think about modern human evolution you know and we've we've seen this model so I've now got rid of the big you know this idea that it's a monolithic branch and it's just lots of populations fragmenting joining up reticulating diverging becoming extinct dying out and in the process they're passing through these thresholds so you know the Simpson threshold apart you know allopatric here in the early in the Eurasian branching processes they become separated allopatric li overtime they may or may not establish the the different you know ecological differences or reproductive differences and the point is that by the time modern humans and Neanderthals meet so I have to look that hex I can't read one of them what data I got I've got the meeting after someone between 100 and 150 thousand years ago probably all these thresholds have been passed but not for genetic isolation so they you know we can they you can then you know depending on your taste you can come back and say well they're not separate species because they haven't passed the final test you know they haven't done their PhD in genetics ever in speciation process they've only got sort of GCSEs at the early stages or you can say no I think for all intents and purposes the we have watched a speciation process going on and I'll say in passing it's probably the best documented mammalian species known can we actually know the behavior that's a sideline of mine are gone about that in other contexts and and then just to sort of wrap this up it reminds us that actually something that matter I have talked about a lot evolutionary geography or biogeography that we always define evolution has changed through time but it starts geographically it's the distribution of populations in space but it's that is so critical and that's that's important and we've seen I think you know it's been a lot of focus on that and I think geneticists need to come to grips with this this problem I mean this paper came out this week you know we all evolved in the aqua bamboo swamp or northern Botswana or something based on the distribution of living populations there today well we've got 200,000 years for them to wander around Africa before we start saying things like that or we could have early scary and colleagues view that the kind of multi-regional pan-african knowledge and I think what we actually need to go back to our basic evolutionary biology the populations start in small areas and they expand they they de stay they dispersed they may or may not add mix and league and clearly the African ones were gathering in other African populations as they did so but that's the model we need to think of we need to think of it at different scales and that's what jits geographical distributions that will ultimately generate our fighters but the genetics cannot pinpoint those in the past because people move and just this isn't again I love showing this one just to remind you that saying that humans evolved in Africa doesn't mean very much at all it just saying we have what we didn't evolve in the new world because Africa can take in Europe the whole of Europe the whole of Asia whole of China can all fit into Africa you've certainly still got room for Belgium and other places it's a vast area so it is an issue where within that we evolved and I think this is my last substantive slide and just to say climate change comes in I've been talking about I chose the title really to talk about climate it's the climate of thinking that we're interested it's changing the way we think about Out of Africa about modern human origins you might be brie making it a more pluralistic and integrated with broader branches of evolutionary biology than the ones which we all specialized in we have to specialize but we have to think that and this but the second element of climate is that there's a lot of climate out there climate change across this period for all these oscillations and if we think of these events there's not going to be a simple story saying when it's warm they do this we're going to find all sorts of funny interactions different once between dispersals and climate from dispersals and behavior extinction is going to relate differently so we have to start to think how to plot those in to get the climate models and I've worked with climate models and had some sort of broad models and things I think we have to be much more specific to think about what parameters of climate are changing what parameters of the human demography and the human evolutionary change and it's just not it's not it's not national it's not in a global problem this is just an East African one there are regional patterns so it's a synchrony is likely to be a significant pattern and not just that it's scale so this is just showing the scale of the one I just showed you the big major oscillations this is just picking out what's this fifty thousand years just in South Africa this is jacobson roberts some people people have questioned these dates but it doesn't matter for the point i'm taking is that you know these are oscillations occurring over a five ten thousand year period so getting the right the scale right is absolutely critical in all this so where are we left I won't summarize this in any detail cause I've gone through most of it already what I want the case I want to make is that there's a bit of tinkering there's quite a lot of grandfather's acts about this and we have changed the handle and we have changed change the head but my philosophical conundrum that I presented you with at the beginning I'd say it's still my grandfather's axe despite that and and that we keep the Out of Africa but we have to think much more flexibly and broadly about the processes that are involved and some of the issues that we we need to look at are outlined there and just to make your life a little bit more difficult just to remind you that modern human origins and I'm a paleoanthropology and I work I probably what most of my career a lot of it much earlier period this is just the tip of the iceberg chaps we need to get the deeper back in time and deal with some of the real problems of twenty-five other taxa of hominins out there for us to understand these processes thank you very much [Applause] thanks very much so since we have time I have two very different ones the first is concerning this cultural phenotype of the Eurasian line lineage is it kind of really now generally accepted that it says symbolic burials Latin and that was had that because recently at least it sounded like there was a lot of discussion around there is discussion I mean nothing you know in my field probably yours too nothing is ever you know the way I think it is people will argue but I think I mean I think there's good I won't give very simple example the only population we have a knowledge of anything down below the neck regularly the skeletons is Neanderthals and it must be because they buried their dead no other hominin you know mostly most hominins leave are scraps of teeth and skull and the odd bone we've got so many full skeletons they must be doing something now I'm whether whether they're doing it to keep the hyenas out or you know because they love love their mother and father I have no idea he's quite interesting that there's in in comparative planetology it's clear of chimpanzees take a lot of interest in dead bodies other animals do so I I don't I personally didn't have a problem with them so I kind of the second question I guess it's less concrete really so what you said about can a phenotype first and the genotype later I think the problem what I have with this is that in evolution for evolution to happen you need to pass from generation to generation information and in fact for complex evolution lots of information so once we have the human language then cultural evolution can start for real because we pass lots of information through language but what's the mechanism before the human language to pass more than just a few bits from generation well I think I mean I think there's quite I means probably work on till cultural evolutionary models too I just go back to the chimpanzees they obviously do transmit social information they're not very good at it because things die out on the other hand our early you know if you look at something like a hand axe I mean that assuming that's not a gene for making a hand out so it's enormous continuity there my guess is they wouldn't have had language like us so I think that's to me listen that's not a problem and we know animals do pass on traditions over a period of time the replicability I mean I you know I think the in a way that I have more of a problem just saying well you know the idea of a mutation coming along at the right time I find very strange and it's much more likely that changes in behavior exposed standing variation that's already there to the to selection and therefore they become favored and then so that these these small behavioral shifts and I'm not talking about big things they're just small behavioral shifts in how you you know distribute yourself across the landscape have a knock-on effect and across the whole of the biology of the organism human language you can other molecules actually is very very few bits really yeah I might be important bits of course thank you it was a very nice talk I just have a comment about genetic divergence states and sort of the need for geneticists to provide like certain date I think genetics can also jump in I think we should start start to try to get away from these very specific divergent states because we now know the mitochondria as a specific divergent state off site 200,000 to Y chromosome goes back to 400,000 and then I think we're going to have various lives so I cross the genome that very different ancestors across the African continent go back to many different times so we're going to have like a range of dates with many different ancestors across the African continent and there won't be one specific time that we can really provide from the genetic site to say this is where our species first diverged it's a good point I mean I take the point that every gene there's going to be a different divergence date I mean some some were predate probably the hominid lineage and so I'm worried I think what what I'm as a user of this information what I really want to know is when when is there an effective demographic divergence taking place and what is the best signal of that mitochondria for example are not a good signal of that in the way we thought it was you know perhaps clearly the whole genomes approach easy in some ways but it gives us a very blurry picture so you know the challenge is to turn as they were from you know single genes giving us a or single no psyche giving us you know a billion different answers to you know having one answer we want splits that relate or split times that relate to particular questions my questions are on the whole evolutionary and geographical and demographic so I shouldn't say the actual history of a particular gene doesn't doesn't interest me as much as the signal the demographic signal is giving me I think it is because this this blurry picture then that emerges is probably close to what actually happened I mean I'm no one saying happen on you know you know October 29th yeah and then xxx whatever day we are you know 4004 years ago it's not it's not I mean on suggesting that I know there's going to be a range but I think we can still in trying to reconstruct the evolutionary history yes I see this is a goal yes yes but I also think that I think I mean what you see in paleontology and what we see in genetics is kind of overlapping because you see these various Africa this idea of the multi-regional origin and these various morphological forms evolving in different places in Africa while we see the similar kind of picture I mean different loci in people have different histories and I might trace back to different parts of Africa and I'm going to talk also more about this you know I talked on Friday but I think I mean we are kind of seeing the similar picture I mean don't we well I mean I don't I think our fossil record is so bad at the moment in Africa we just need more it's very difficult to say what is evolving we're in this period I mean we can do you know the origins of modern humans compared to heidelbergensis but we can't do the texture because the fossils on there Thanks thanks Rob following on from Karina's point I think what she wanted to say is that genetically in and given you know the second half of your talk there may not be such a demographic event to pinpoint but I think the question is is there anything in the fossil record that suggests otherwise that we cannot think of you know middle to late pleistocene Africa as the place and time for kind of human origins and in is there anything in the archaeological record that suggests that we can go more kind of narrow geographically or temporally than that well I suppose in the archaeological record I would say you know the the the evidence for the earliest Middle Stone Age is strongest in East Africa and I think that's where we kind of expect it how much we can you know so I think I you know I expect us to be able to refine it down to that sort of level at the moment I don't think we can with the fossils because we just don't really have enough of them to say you know there's these different regions and bear in mind also how and I showed the climatic how dynamic these things are so what we call East Africa we forget about as East Africa and think about it as a type of environment it goes all the way up in deep into North Africa at certain times and a lot of times it's constricted just more later so we would struggle to do that but I would you know I think we can we certainly shouldn't be aiming to pinpoint it you know more closely because I said you know saying we evolved in Africa is not it's not saying very much yeah thanks by the way just I don't know our comment so from genetics now we are all ready to embrace the concept of admixture right the idea the different lineages cannot mix but from cultural and behavioral perspective we still seem to think in a very you know cladistic way I don't know like know you you made a point of convergence versus common ancestor what about cultural admixture interaction for example we have these artists in your final slide what penultimate there was a model of maybe African sapiens neanderthalensis Aden Neanderthal behavioral change red block and certain behavior change red block well maybe it was interaction yeah crazy and thank you for the diagram good yes okay yes we do need you I would say I tend to sort of do a lot of tree building and archeological things because on the whole archeologists are very reluctant to think I mean they actually I probably do not represent the field terribly well because I think they would do much more in line saying well it's all kind of flowing together and clearly information is flowing I mean the shuttle perón ian the you know their culture ation late yeah that's what it was a paper earlier this month you know saying that actually you know none of the chronology makes any sense for that so you know we don't know I think the real problem is culturally I mean just think acculturation if we understand it as taking place it's likely to occur over a period of hundreds of thousands of years max okay if I could you know where the sort of information we have we're lucky if we put it into 10 20 30 40 50 thousand year brackets so trying to then pick up what might be cultural you know culturation versus I thought a fricative versus what might be a dispersal is gonna be very very difficult to do I mean I agree we should and then you're absolutely right the flow of traits I mean you know just to come come on the add genetic admixture side of things I mean we all emphasize it but I sorry we we forget the fact how small it is it's not a big con okay in one generation one it must have been massive however the the actual overall impact was very small on humans most of human genes that come from that African ancestry so ask the same question about cultural things it might be that a few things are dribbling across but is the bulk of cultural transmission done through phylogenetic final Genesis rather than horizontal transfer I mean linguists are you know make the same sort of discussions about things I mean I would say these are the major questions we should be addressing in the next 10 years or so well you should be addressing in the next 10 years or so [Applause]
