The conventional wisdom about the migration of Homo out of Africa, where the genus originated, involves the spread of Homo erectus about 2 million years ago across Eurasia, with that species appearing to have gone extinct without issue.
After that, the Neanderthals, which split from the lineage producing “modern” (i.e., living) H. sapiens about 800,000 years ago, moved to Europe some time between then and 600,000 years ago. (For convenience, I’ll call Neanderthals “Neanderthals” and “modern H. sapiens” as sapiens, though I think they’re both subspecies of H. sapiens.)
Then, it was thought, sapiens moved into Europe and then Asia beginning about 60,000 years ago, with Neanderthals becoming extinct around 40,000 years ago, though having left a genetic legacy within sapiens. (That ability to produce fertile hybrids between H. sapiens sapiens and H. sapiens neanderthalensis is why I consider both lineages to be subspecies of the same biological species).
There was, however, tantalizing evidence—as summarized in a Nature News & Views article (free with UnPaywall) about the paper discussed today—that two skulls found in Israel, dated between 500,000 and 200,000 years ago, might also been close to the “modern H. sapiens” lineage, but the evidence is fragmentary and these could actually be Neanderthals.
The figure below, from the News & Views piece, summarizes fossil finds of Homo from the Eastern hemisphere (see key at bottom of figure for species designation, and note the Neanderthals and Denisovans):
The Israeli fossil provided weak evidence that sapiens may have left Europe well before the conventional date of about 60,000 years, though these forays into Eurasia, at least judging from genetic evidence, didn’t give rise to humans living today.
Now a new article in Nature by Katerina Harvati et al. (click on screenshot below for free UnPaywall access, with pdf here and reference at bottom), suggests much more strongly that sapiens did indeed leave Africa for Eurasia much earlier than we thought: in fact, way earlier—about 210,000 years ago. That more than triples the time length of time since the first sapiens left Africa. Note, though, that the new find, even if it is sapiens (and there are doubts), is not ancestral to living modern humans; the population seems to have vanished without issue.
The paper is based on two skulls originally found in 1978 in a cave in Apidima in southern Greece, but were only now dated and thoroughly analyzed morphologically.
There were two skulls in the same place and piece of sedimentary rock, one dated at about 170,000 years ago (“Apidma 2”) and the other a bit older at 210,000 years (“Apidima 1”). Apidima 2 is represented by a pretty complete cranium, minus the jaw, while Apidima 1 is only the rear of the skull. The fossils are shown below, with Apidima 2 at top. Both are pretty badly banged up.
(All figure captions are from the Nature paper).
Because the skulls were so incomplete, their shapes had to be determined through reconstruction by computed tomography; and for Apidima 1, which has no face at all, the rear of the skull was reconstructed by making a mirror image of the better-preserved half. This fragmentary nature of Apidima 1 has to be kept in mind when assessing what it was.
The take-home lesson from the paper is that the dating and structural studies (done through uranium series analysis) shows that Apidima 2 falls well within Neanderthal types, but Apidima 1 shows features that lead the authors to conclude that it is indeed sapiens. These sapiens features include a more rounded rear of the cranium as well as the lack of a characteristic Neanderthal trait, a bulge at the back of the skull like a bony hair bun. As the authors say, using morphological argot that you can skip (I’ve eliminated references in the paragraph below):
By contrast, Apidima 1 does not have Neanderthal features; its linear measurements fall mainly in the region of overlap between taxa. It lacks a Neanderthal-like rounded en bombe profile in posterior view. The widest part of the cranium is relatively low on the parietal; the parietal walls are nearly parallel and converge only slightly upwards, a plesiomorphic morphology that is common in Middle Pleistocene Homo. It does not show the occipital plane convexity and lambdoid flattening associated with Neanderthal occipital ‘chignons’. Rather, its midsagittal outline is rounded in lateral view, a feature that is considered derived for modern humans . The superior nuchal lines are weak with no external occipital protuberance. In contrast to some Middle Pleistocene specimens, the occipital bone is not steeply angled and lacks a thick occipital torus. A small, very faint, depression is found above the inion Although suprainiac fossae are considered derived for Neanderthals, similar depressions occur among modern humans and in some African early H. sapiens. The Apidima 1 depression does not present the typical Neanderthal combination of features. It is far smaller and less marked even than the ‘incipient’ suprainiac fossae of MPE specimens from Swanscombe and Sima de los Huesos, and is closest in size to the small supranuchal depression of the Eliye Springs cranium, a Middle Pleistocene African (MPA). Apidima 1 therefore lacks derived Neanderthal morphology, and instead shows a combination of ancestral and derived modern human features.
The placement of Apidima 1 with sapiens and Apidima 2 with Neanderthals is shown in the following two graphs, where known fossils are grouped and identified with dots of various shapes. In the following, “modern” sapiens are blue triangles, Neanderthals are red stars, Middle Pleistocene Eurasians are yellow squares, and Middle Pleistocene Africans (presumably sapiens) are purple squares. The two axes represent various “principal components” that capture combinations of shapes and measurements that help distinguish specimens.
“Rec 1-4” are the reconstructions of Apidima 2. As you see, they fit pretty nicely within Neanderthals, or are closer to them than they are to sapiens (blue polygons). This is why Apidima 2 is considered a Neanderthal skull.
Here is Apidima 1, which is labeled as a diamond symbol in both left and right. As you see, it falls within the sapiens parameters and isn’t near the shape of Neanderthal skulls (red stars).
Finally, here’s a different analysis that places both Apidima 1 (black triangle) and reconstructions of Apidima 2 (“Rec 1-4”) on one plot. Apidima 1 is close to “modern sapiens” (blue polygon(, but falls between it and early H. sapiens from Africa (purple polygon), demonstrating that, while sapiens-like, it wasn’t fully “modern” in its morphology.
Apidima 2 falls squarely within the ambit of Neanderthal skulls (red stars).
So there you have it: decent but not wholly convincing evidence that sapiens had already left Africa 210,000 years ago, and lived in the same period and place as Neanderthals. That’s a long time before we thought, and constitutes a dramatic revision of how we thought humans moved about in the last few thousand years.
A couple of questions remain:
How reliable is this conclusion? Well, I’m not a paleontologist, so I won’t put a definitive imprimatur on this diagnosis. In his News & Views piece, Eric Delsen notes that “Given that the Apidima 1 fossil and those from Misliya and Zuttiyeh (latter from Israel) are only partial skulls, some might argue that the specimens are too incomplete for their status as H. sapiens [JAC: they mean “modern H. sapiens”] to be certain. Delsen suggests that “paoleoproteomics”—sequence analysis of ancient proteins from the skulls—might help resolve this issue, even if DNA isn’t available.
Chris Stringer, one of the paper’s authors, issued a tweet that Matthew retweeted, praising it for its rigor and scrupulous honesty (Stringer says the reaction should be “a healthy skepticism”):
Now this take from Chris Stringer is rigorous and scrupulously honest. Oh, and fascinating! If true, this puts humans in Europe 150,000 years earlier than we thought. Here’s the paper: https://t.co/2tTKMa8wLA https://t.co/VDe4T2Hzk3
— Matthew Cobb (@matthewcobb) July 10, 2019
Did these early-emerging sapiens have contact with Neanderthals? Perhaps, though the dates of the two skulls are 40,000 years apart. But there is evidence for a long persistence of Neanderthals in Greece, so it’s likely that the two subspecies did coexist in the same general area. But if they mated with each other, there are no traces of that Neanderthal DNA in modern humans, which helps answer the next question:
If this fossil is indeed sapiens, what happened to the population? The authors suggest that the sapiens population simply died out without issue, and that’s supported by genetic data suggesting that all modern humans descend from an egress from Africa about 60,000 years ago. The Greek population may have simply gone extinct by attrition, or may have been wiped out by Neanderthals. Who knows? But if they died out without issue, as is likely, they are not our direct ancestors.
As Steve Gould used to say, when he taught human evolution every year he simply dumped his previous year’s teaching notes in the trash and wrote an entirely new lecture. That may have been an exaggeration, but shows how rapid the pace of understanding human evolution was. And still is! Given the paucity of finds in the genus Homo, there are many surprises to come.
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Harvati, K., C. Röding, A. M. Bosman, F. A. Karakostis, R. Grün, C. Stringer, P. Karkanas, N. C. Thompson, V. Koutoulidis, L. A. Moulopoulos, V. G. Gorgoulis, and M. Kouloukoussa. 2019. Apidima Cave fossils provide earliest evidence of Homo sapiens in Eurasia. Nature, online.
Well, I am unimpressed. There has been quite a lot of push back in the paleoanth community lately about these articles that claim “the first humans…” These fossils are old. But, there is some genuine doubt as to how modern they appear (could be Neandertals). Even if the two skulls are physically modern H. sapiens, there is no evidence they established a viable population in Europe at that time. So, a few modernish-looking people may have strayed into Europe long before their kind made a genuine migration into that continent. That is not terribly surprising or significant.
Well, it does add to our knowledge about how and when our relatives moved about, and certainly changes the “out of Africa” scenario.
I am unimpressed that you are unimpressed. I thought this was interesting, and you apparently haven’t read the way the authors attack the idea that the sapiens skull might really be Neanderthal.
Allow me to clarify my original statement. I am unimpressed with what I saw in the media coverage of this research, not your summary (in fact, very well done!) or the research in general. Of course, it does add to our understanding of human prehistory which alone is valuable. I had seen several reports on this already by the time I read your summary. Many had attention-grabbing headlines suggesting this find has fundamentally altered our view of Homo sapiens and Neandertals. It hasn’t.
Most of the press coverage also tends to equate the term Homo sapiens to mean anatomically modern people. Of course, this is not the case here, as the Greek skulls are not anatomically modern, but at least one does look to be Homo sapiens. When I was a grad student (my background is paleoanthropology), the term “Archaic Homo sapiens” (AHS) was popular. However, some correctly pointed out that the term is not a valid taxonomic category — you’re either Homo sapiens or you’re not (unless you want to talk about subspecies, which are also generally avoided when discussing humans). Many fossils that we called AHS were then lumped into Homo heidelbergensis, an old name that has a a single mandible (Mauer 1) as the type, thus of limited use when comparing crania.
One thing I really do appreciate from this research is that people are once again discussing Archaic and Modern-looking Homo sapiens. But, this discovery is not terribly surprising given what we already know of the distribution and age of these non-modern looking Homo sapiens in Africa.
What do you mean by “viable”? Seems to me that for anyfossil to be found you would need a population that is “viable”. If a population goes extinct, that doesn’t mean it wasn’t previously “viable”.
Perhaps the wrong word, but I meant that they did not establish a population in Europe that appears to have persisted for any significant amount of time. Like Vikings in North America, they didn’t appear to stay.
Given the age of these fossils and the low probability of preservation, I would expect that any find probably represents a relatively viable (in your use) population. “Vikings-in-America” (so to speak) would almost certainly not be found in the record after a couple hundred thousand years simply because the source population was so small. I think that when we find fossils (of anything) there was once a reasonably decent-sized population. These guys just died out at some point.
The Greek fossils demonstrate that modernish-looking humans managed to populate a portion of Europe for a time and then disappeared. This is quite a bit different from the events that occurred more recently (about 40,000 years ago), where modern humans appear to have arrived in Europe and within a relatively brief period became the sole hominin species there – quickly inhabiting all parts of the continent while the previous residents, the Neandertals disappear fairly abruptly, after having inhabited Europe for over 200,000 years or so. While an early foray into Europe by modern humans is certainly interesting, the bigger question to me is, what prevented them from successfully inhabiting Europe until about 40,000 years ago? Stringer suggests there may be European sites with only archaeological remains (stone tools and such) without fossil hominins that could be modern human sites we are mistaking for Neandertal sites. I don’t think that is likely, especially if modern humans arrived with their own material culture from outside Europe.
I’m not at all that small widely distributed populations would fail as groups expand into marginal areas. That’s to be expected, I think. What I find more challenging is to figure out what made the ones who finally did succeed (so far) successful. It could be down to random events.
It is simply because the massive eurasian expansion started 50,000 years ago from south Asia. So yes, even if Humans quit Africa 70-75,000 years ago (and not 60,000 as is claimed on this website), no expansion wave prior to 50,000 years ago yielded modern survivors. 45,000 years for Europe is only about 5,000 years after the start of the demographic boom, which is reasonable.
I don’t know if, or how many, Vikings may have made it from L’Anse aux Meadows on the coast of Canada down along what are now northern U.S. waterways. But, some people believe there is evidence that they traveled as far down as Rochester, MN. I also don’t know if most, or all, of the Vikings were blue-eyed but, they or some other European travelers made it inland in the U.S. as far as the Mandans, some of whom have been known to be blue-eyed.
“… some people believe there is evidence that they traveled as far down as Rochester, MN”
Perhaps even: many so believe. And they all talk to each other. So although perhaps none know specifically who it might be that has the evidence, they all come to believe in this possibly mythical being. But if such a person is real, I’ll bet all the so-called evidence is weak to vanishing.
Does it occur to these people that mid-west US tribes who have the occasional blue eyes might just have had sexual interaction with some European(s) arriving (or with ancestor arriving) after 1491?
Would travelling there by “waterways” from the coast of U.S. involve water flowing uphill over the Appalachian or other range of mountains? I’m guessing rather that you are referring to the supposed penetration of Greenland Vikings, going way past Baffin Island and into Hudson Bay, then down through Manitoba,… Firstly there is no reason to believe any such thing has anything to do with the short-lived colony (or perhaps colonies) in Newfoundland. In fact there is no evidence I think of anything remotely like that deep incursion of Vikings into what is now Canada, much less U.S.
I’m a ‘big Viking fan’. But the Greenland Viking appear to have been far less competent at facing the little ice age (so-called??) than were the Inuit.
There may be some evidence of Viking interaction with Inuit on Baffin Island, but
1/ very weak to vanishing evidence of any over-wintering,
2/ a strange instance of the academic involved in that research not continuing, and
3/ it was the east coast of Baffin.
I think ‘hogwash’ is pretty close to the best description of any claims about Vikings arriving anywhere in the U.S. midwest; and further that a supposed ancestry line backwards from any time after, say, 1600, a line which remains within the two continents (known to all but USians as America) until it arrives back in Viking Greenland (of course before that time), that such a sequence of people simply doesn’t exist.
Even the Beothuk indigenous of Newfoundland, with whom the l’Anse Aux Meadows Vikings interacted, apparently in only a hostile manner, were later hounded to extinction. However some probably do have present-day descendants, via that much more frequent sexual interaction ‘outside the band’ pointed out by Adam Rutherford (A Short History of Everyone Who Ever Lived) and David Reich (Who We Are and How We Got Here).
Vikings made it to Minnesota but only in the form of football players.
Well, to a non-expert, they seem to have got a hell of a long way from Africa. That surely suggests a viable breeding population existing and thriving over quite a number of generations.
I disagree that the discovery of modern humans so early in Europe is not significant. Down thread Historian linked to an Atlantic article discussing these finds and in it we find;
If modern humans were in Europe before 40k years ago, some of those tools may have been theirs, not the Neanderthals. I think that’s pretty significant
I think that the stone tool kits of modern humans arriving from Africa would be distinguishable from the stone tool kits of Neandertal populations that had been inhabiting Europe for tens of thousands of years.
Thanks for this analysis.
Thanks again for taking the time to do these detailed commentaries on recent papers. I read the paper, as well as some other stories that quoted other researchers. I agree that the authors did a meticulous analysis with what they had available to them. However, it still comes down to the equivalent of a single data point. The unfortunate thing is that we have a very small sample to establish within-group variation that would allow us to better assess differences. On the other hand, as with the Denisovans, this find may lead to a better understanding of the complex history of our species.
There are plenty of surprises to be encountered this deep in the past!
I appreciate this analysis, the chaff spread through the cyberverse can make reading these types of stories in the Press Battlewagons perilous.
Reblogged this on The Logical Place.
Sub
It would be very interesting if these earlier false starts occurred. That earlier moves did not survive is not surprising but to know what caused the failure is very unlikely. I suppose if they had survived it would be more surprising.
I’d guess climate would have been very different for the two emigrations. This could have made a difference.
At the Atlantic, Ed Yong summarizes the findings, accurately, I hope.
https://www.theatlantic.com/science/archive/2019/07/apidima-greek-skull-oldest-human-fossil-outside-africa/593563/
A very good summary by Yong, who is a gifted science writer. He points out some interesting things.
He quotes Rebecca Wragg Sykes: “But “it doesn’t look like classic Homo sapiens,” says Wragg Sykes, who wonders whether it represents a group of humans that had been interbreeding with Neanderthals or other ancient hominins.”
So, are the skull really anatomically modern Homo sapiens?
Wragg-Sykes then goes on to say later: ““We can’t refer to Homo sapiens as a ‘success’ in terms of being able to move into new areas and stay there,”
Anthropologist Shara Bailey says: ““We may find the first anatomically modern humans lacked the kind of advantages that later Homo sapiens may have had”—the very same advantages, she says, that led to our “ultimate domination.””
To me, this is the paleontology equivalent of finding an animal outside of, but not too far from, it’s typical known range. Interesting, yes. But is this find really “rewriting our understanding of humans and Neandertal in Europe” as the headline suggests?
A question about the subspecies point. I thought that the existence of fertile offspring in the wild was what defined the species boundary. So I am confused why anyone would disagree with you. Am I missing something?
Well, I’m using the biological (evolutionary) species criterion, but others define species by morphology or genetic distance, and they may see Neanderthals and “modern” H. sapiens as separate species. There are, after all, several dozen species definitions, though I think the BSC is the most useful from an evolutionary perspective.
I’ve always regarded the BSC as the “proper” definition of a species, and all the others as approximations to it for cases when we can’t actually check for interbreeding with fertile offspring.
Is that reasonable or am I overclaiming for the BSC?
Definitions are tools that should be measured against usefulness. (Because what would “correctness” be?)
Seems the 3 most useful species definitions are the biological (for population data), the genomical (for gene data) and the morphological (for fossil data). If we can apply several definitions and are careful, they may even agree!
Being able to produce fertile offspring is a good criterion, but modern H. sapiens and Neaderthals are a fuzzy area. Hybridization was possible, but there is evidence that this came with significant fitness costs:
https://www.genetics.org/content/203/2/881
Some researchers have argued that hybrid males were infertile, as we don’t see Neanderthal DNA on the Y chromosome. However, the reasons for this are controversial:
http://blogs.discovermagazine.com/gnxp/2011/04/neandertal-hybridization-haldanes-rule/#.XSjejXtMGUk
Defining species involves some subjectivity and I’m sure that we’ll still be debating this 100 years from now.
Good analysis, seems you covered all the latest data (what I know of)!
This is a very interesting detailed analysis, but readable by those like me who are ignorant of biology.
Would it not be surprising if, after minus 300,000 years (or whatever date is most suitable for the advent of anatomically modern humans) there had never been incursions of small groups of them, well beyond whatever suitable line you draw for the start of Eurasia, but happening before, say, minus 70,000 years (or again whatever date is most suitable for that unique incursion which is the first and only major one which does have present day descendants, a large majority of all of us)? And so all the earlier such incursions are without now living descendants (but see below).
Or am I misunderstanding rather badly?
I do realize that it is very very slightly possible that a rare mating, with a Neanderthal, of someone in an earlier incursion, followed much later (say, minus 45,000 years) by a mating of one that (resulting) Neanderthal’s descendants with another modern human, could possibly end up causing present day people to have an ancestor from one of the earlier incursions.
The thing I listen for and never hear is any speculation on how the various Ice Ages and Interglacials may have affected these migrations. Hominin populations must have been pushed back into equatorial refugia in the glacial periods, and this must have had some impact on the mixing of the two groups, mustn’t it?
I’m just impressed that they were able to hoof it all over the place. I, a person with foot pain, am envious of their foot prowess and think of myself as an evolutionarily unsuccessful descendant. 🙂
Sub
I am a little confused by this because I thought the first anatomically modern humans were only 200,000 years ago.
If the date is correct, I would assume that “modernish” H. sapiens were going back and forth between Europe and Africa for at least 200,000 years. If they left Africa 200,000 ago and 60,000 years ago, it is likely they left other times inbetween. Presumably the European had small populations with few ancestors of modern H. sapiens.
I think the lineage that branched off from others and led to modern Homo sapiens, though of course it wasn’t identical to modern H. sapiens, arose about 350,000 to 300,000 years ago. That was well before this fossil. And remember, “anatomically modern” is a rather slippery concept, because they weren’t identical to modern humans, nor is this fossil.
Recent research has re-dated a well-known fossil skull at Jebel Irhoud (Morocco) of Homo sapiens at 300,000 years old. The skull is not completely modern, as the article points out it has an archaic elongated skull (not the rounded skull we have). But definitely “modernish” as you say. Easy to see how a group of these hominins could have made it to Greece from North Africa.
https://www.sciencemag.org/news/2017/06/world-s-oldest-homo-sapiens-fossils-found-morocco
I am confused by their reference material too, since the rounded skull domesticates of H. sapiens evolved about 100 kyrs ago (just before the Out-Of-Africa event) and those are what they compare with. The Middle Pleistocene material should end about 200 kyrs ago, but they say “early” MP humans. As usual, the answer to what material they used is buried in the non-published data, infuriating.
We know that there was interbreeding – could this be one?
Am I the only one wishing for a time maschine?
It doesn’t sound far fetched that modern H.S. migrated into Europe when the climate allowed it. The Neanderthals were a lot better adapted to harsher conditions, so when the ice came back the modern (or perhaps modernish) humans got pushed back. The last wave of African immigrats, our ancestors, were I guess lucky. We have some genes from our cousins that helped our adaptation to Europe. Earlier gene flow is at the moment not detectable. Not long ago it was deemed impossible to sequence ancient DNA, who knows what the guys at the MPI in Leipzig can come up with in the future.
With these rare finds it’s always possible we are dealing with just a weirdo individual that doesn’t represent other individuals in its group. I remember similar arguments about whether “Lucy” and australopithecines should be considered direct ancestors of homo sapiens.
Maybe if we’re looking at a true representative of other homo sapiens, they died out for not meeting up with Neandethals (speaking as someone with a higher than average Neanderthal lineage) 🙂
Plenty to ponder.
I couldn’t get any peace and quiet today and couldn’t focus on this post. Just finished reading. Thanks. Have nothing substantive to add, except I also learned from the readers’ comments, which is always a plus regarding science posts. WEIT is priceless!
Finally getting to read this. Thank you so much for this summary.
I am something of a science idiot, but with an interest, and want to read the kinds of judgments you make.
Thanks for the article, added some perspective!
Seems the dating is the most shaky part of the analysis, but the PCA of the partial Apidima 1 skull is problematic too. The paper states that they want to do the best with modern tools, and the Apidima 2 skull is such an analysis. Even so the PCA of the 4 separate reconstructions is pushed outside the boundary of the known Neanderthals; but symmetrically so, making the identification reasonable and showing how the presumably younger skull is heavily distorted.
Nothing of that careful analysis is evident in the Apidima 1 analysis. Without discussing the amount of deformation before or after the single reconstruction they slice a plane through the preserved part of the sagittal suture, mirror the remains and join the two parts. The center join is the most uncertain part of a profile, yet it is precisely that they use as central data set in a series of landmark PCA. The one they use has a reference that use that method on landmarks of whole skulls, and they could easily have done the same, adding data while avoiding introducing uncertainty; again no discussion of their choices and of the forerunners better use of fossil material.
In sum, their underlying analysis is either wrong, too sketchy and uncertain, or possibly acceptable. In the latter case their result suggest an affinity to extant humans that did not evolve until about 100 kyrs ago, on the opposite side of the Neanderthals where contemporary Middle Pleistocene are found. And as we have come to be used to in the paper, that idiosyncrasy was not discussed.
The journal Science (July 12, 2019 issue) has a good summary of the skepticism by several paleoanthropologists regarding these skulls.
One of the things they mention is that the dates for these fossils are by no means certain. Such cave sites are notoriously difficult to date and range of error is NEVER reported in popular press. In fact, the variation on the dates ranges from 400,000 years ago to as recent as 40,000 years ago!
https://science.sciencemag.org/content/365/6449/111