Tuesday, May 11, 2010

Neanderthals'r'us?

By now, unless you live under a rock, you should have heard the news: New genetic studies indicate that Neanderthals and modern humans likely interbred:

Among the findings, published in the May 7 issue of Science, is evidence that shortly after early modern humans migrated out of Africa, some of them interbred with Neanderthals, leaving bits of Neanderthal DNA sequences scattered through the genomes of present-day non-Africans.

"We can now say that, in all probability, there was gene flow from Neanderthals to modern humans," said the paper's first author, Richard E. (Ed) Green of the University of California, Santa Cruz.

The results of the study have been published in two papers in the last issue of Science (Green et al. 2010, Burbano et al. 2010 - both free access), where you can also ResearchBlogging.orgfind a free online feature. that provides some context to the public unfamiliar with genetics and/or Neanderthals To get a better idea of the significance and the nuts and bolts of this new work, you must, must go over to John Hawks' blog for a very thorough discussion. I largely agree with his take on the reports and what they mean, but as I've argued elsewhere, we need to reconcile the genetics with the fossil, and especially the archaeological records. Just as there was a great deal of well-founded skepticism by some about 'X woman' a few weeks ago (something which I've been meaning to write about and hopefully will get to relatively soon), people need to come to grips with all of the available data, as opposed to considering one line of evidence as trumping all others. In other words, it's not because some people wear lab coats that their data by definition trump all other!

In practical terms, I think this means that you will see a lot of people more sympathetic to a replacement position start arguing just that, that you need to reconcile these new genetic data with previous data that seemed to strongly support such a position (just how strongly is debatable, but besides the point here). Specifically, I think you'll see these people focus on caveats of genetic studies like they never have before, and latch on to less parsimonious explanations of the genetics as 'something that needs to be considered seriously' (in this case, though, the alternative interpretation is so much less parsimonious as to be untenable). Fundamentally, of course, there's nothing wrong with that; in fact, it's something I've argued for repeatedly both on this blog and in press (link to a free pdf on the Uluzzian). The key difference is that if people on both ends of the spectrum will (hopefully) begin playing by the same general rules.

Now, does this mean that it's time to do the Neanderthal victory dance (to quote Hawks) and to begin re-imagining the caves of Late Pleistocene Europe throbbing to the sweet rhythms of Barry White and Marvin Gaye? Well yes and no. Yes, there is no some fairly conclusive evidence that Neanderthals and modern humans interbred and yielded fertile offspring - this means that, from a purely biological standpoint, the two were part of the same species, Homo sapiens. But no, it does not directly answer the question of how and why Neanderthals ultimately disappeared. And also, NO!, "Let's get it on" is not now a sufficient way of thinking about the relationships between Neanderthals and early modern humans!

That said, in my opinion, the two papers papers (Greene et al. 2010; Burbano et al. 2010) have the potential to considerably change how Neanderthals are discussed, both in terms of how people approach the data and how the data is interpreted, which are slightly different things. First, the people, namely researchers involved in modern human origins research. For one thing, as I mentioned above, you're likely going to hear much more frequent calls to consider all the evidence available and how it agrees/disagrees. On the other, in order to best incorporate all the relevant data in interpretations, the debate should shift away from 'one size fits all' interpretations to interpretations that are more regional in scale. Whether or not any of this actually happens is another story, but these papers definitely have the potential of serving as game changers in the modern human origins debate.

What I find most exciting about the Green et al. (2010) study is that it provides a strong boost for the importance of archaeological evidence plays in understanding the process by which Neanderthals disappear. Quite simply, this is because the genetic data and the skeletal evidence (Trinkaus 2007) now both converge to show some significant degree of biological interaction between the two homminin populations. The thing is, genetics and physical anthropology informing us about the fact that such interaction took place, but they tell us comparatively in terms of how these interactions played out. This is where archaeology comes in, since it's the only way we have of getting at the various types of interactions Neanderthals and modern humans might have had and to remove the preconceptions implicitly imposed by the notion that they were two distinct species.

In practical terms, we should now thankfully be moving away from models that see Neanderthals as fundamentally different from 'us'. This means that there is little reason to continue depending on interaction models that see Neanderthals as merely 'copying without understanding' whatever different behaviors early Eurasian modern humans might have displayed. An extension of that is that if Neanderthals and modern humans interacted enough for the former to have contributed between 1-4% of the genetic material of people of non-African extraction today, the two groups must have been able to interact in a sustained manner, which rules out a scenario whereby rape plays a preponderant role (and plays on prevalent ideas of Neanderthals as the savage/dangerous other). This also has implications about communication between the two groups, by which I mean that they likely were able to speak to one another, as already suggested by both genetic and indirect evidence anyway.

Perhaps most interestingly is that the degree of genetic contribution of Neanderthals to modern human genetics also sheds some light about how intense the interactions might have been, and also what some of the demographic parameters of thee encounters might have been. The numbers do point to some kind of demographic imbalance, though it must also be remembered that genes, like culture, can sometimes diffuse into an area much in advance of the arrival of a new population (Eswaran 2002, Eswaran et al. 2005). In other words, modern human genes might have made their way into Neanderthal areas by virtue of Neanderthal-hybrid interactions as opposed to necessarily only through Neanderthal-modern interactions. What this means for how 'hybrids' might have been perceived or integrated in either population is open to debate, but is a debate that might well shift to the center of ongoing debates about the nature of interactions between prehistoric humans populations.

References

Burbano, H., Hodges, E., Green, R., Briggs, A., Krause, J., Meyer, M., Good, J., Maricic, T., Johnson, P., Xuan, Z., Rooks, M., Bhattacharjee, A., Brizuela, L., Albert, F., de la Rasilla, M., Fortea, J., Rosas, A., Lachmann, M., Hannon, G., & Paabo, S. (2010). Targeted Investigation of the Neandertal Genome by Array-Based Sequence Capture Science, 328 (5979), 723-725 DOI: 10.1126/science.1188046

Eswaran, V. (2002). A Diffusion Wave out of Africa: The Mechanism of the Modern Human Revolution? Current Anthropology, 43 (5), 749-774 DOI: 10.1086/342639

ESWARAN, V., HARPENDING, H., & ROGERS, A. (2005). Genomics refutes an exclusively African origin of humans Journal of Human Evolution, 49 (1), 1-18 DOI: 10.1016/j.jhevol.2005.02.006

Green, R., Krause, J., Briggs, A., Maricic, T., Stenzel, U., Kircher, M., Patterson, N., Li, H., Zhai, W., Fritz, M., Hansen, N., Durand, E., Malaspinas, A., Jensen, J., Marques-Bonet, T., Alkan, C., Prufer, K., Meyer, M., Burbano, H., Good, J., Schultz, R., Aximu-Petri, A., Butthof, A., Hober, B., Hoffner, B., Siegemund, M., Weihmann, A., Nusbaum, C., Lander, E., Russ, C., Novod, N., Affourtit, J., Egholm, M., Verna, C., Rudan, P., Brajkovic, D., Kucan, Z., Gusic, I., Doronichev, V., Golovanova, L., Lalueza-Fox, C., de la Rasilla, M., Fortea, J., Rosas, A., Schmitz, R., Johnson, P., Eichler, E., Falush, D., Birney, E., Mullikin, J., Slatkin, M., Nielsen, R., Kelso, J., Lachmann, M., Reich, D., & Paabo, S. (2010). A Draft Sequence of the Neandertal Genome Science, 328 (5979), 710-722 DOI: 10.1126/science.1188021

43 comments:

Anonymous said...

I take issue with the thought that intrebreeding with fertile offspring certainly means same species.

Don't get me wrong, given the human propensity to have sex with, well, pretty much anything, I've often wondered about the assertion that there was never any gene mixing despite thousands of years of overlap of populations in places. Nevertheless, those of us who have dealt with coy-dogs, and who know perfectly well that Canis latrans and Canis lupus are not the same species, scoff at your assertion that organisms MUST be the same species to create fertile offspring. There are plenty other examples, too, notably among bears and birds, where hybridisation can happen in the wild & without human intervention where populations overlap, and offspring are interfertile with parent populations as well as each other.

Julien Riel-Salvatore said...

Thanks for the comment. Scoff if you must, but the point I'm making is that if one subscribes to the biological species concept, then Neanderthals and modern humans should be considered the same. Of course, whether a biological species concept is appropriate to think about organisms that we know only from fossil and partial genetic evidence is an open question, but given that implicitly much prior work on Neanderthals has focused on demonstrating that biologically they were not the same species as Homo sapiens, the Green et al. paper is a pretty big deal. Now, we have some fairly secure data from which to argue that Neanderthals contributed genetic material to modern human populations, traces of which endure to this day. My main point here was that, with these observations in hand, we can start trying to develop more complex models to reconcile the archaeological, morphological and genetic data to better understand how and why Neanderthals disappeared - the question, as I clearly stated, is far from resolved, and in some ways has been made more complicated by these data. The key thing, really, is that given the disproportionate weight given to genetics in the modern human origins debate over the past two decades, getting data that run counter to accepted models will (or at least should!) force people to develop better models and to thoughtfully use all of the evidence available to develop models that are applicable for given areas and serve as a way to generate testable hypotheses about this process that can then be tested against the record of different areas. If anything, I'd hope that paleoanthropologists sensu lato can now start drawing from chronologically much more shallow biological datasets (such as the coy-dogs you mention) in order to devise better models of the interaction between Neanderthals and modern humans - of course, here too, the biological data would shed light on only one facet of the question.

Ken said...

The main thing to remember about the interactions is Neanderthals were defenceless against humans' ability to throw spears while maintaining a safe distance with their superior mobility. By my way of thinking the later Neanderthals would have regarded humans as a deadly dangerous predator and be panic stricken when they saw one. Is there a precedent for a animal to hybridize with a species that preys on adult members of its species?



What did humans do the nasty with first, sheep or wolves ?

Answer wolves because they were tamed 100,000 years ago

The only possibilty for a European Neanderthal to mate with its most deadly dangerous predator would be capture as an infant and being kept as a pet.That would explain why the genes flowed one way; the offspring all were born into a band of humans.

A human who tried mating with a 'wild' Neanderthal would not 'get it on'; they would get their anatomy twisted off.

Anne Gilbert said...

Julien and Luna:

I think the "coy-dogs" example is a relevant one, at least in some ways. I have "studied" wolves for years(always hoping to hear or see one in the wild, but that's another story). One of the things I've discovered is, that all members of the genus Canis are capable of producing fertile offspring. And there are "wolves" in certain parts of the country that have coyote mtDNA, and there are also "coyotes" that have "wolf"mtDNA. I think much of what has been said is probably true of the genus Homo, and I've felt this for some time now. Are wolves and coyotes(and, for that matter, domestic dogs and jackals) one big species? Was the genus Homo? I don't know. I leave that for better minds than mine, but the Pääbo study has confirmed a picture I had of patterns of Neandertal/"modern" interactions, and which has been incorporated to some extent in my Great Medieval Science Fiction Masterpiece With Neandertal, along with several other discoveries along the way.

I should add that I do think it is important that we look for larger patterns here, of interaction, ecology, population size, behavior, etc., etc. and not just between Neandertals and "moderns", but perhaps at Homo as a whole(if we can extract enough DNA or do enough archaeological work, but of all members of the human genus. This particular study is too new to be fully incorporated in the human evolution story at present, but I think exciting times are ahead.
Anne G

Julien Riel-Salvatore said...

Ken -
there's no evidence that humans were predators on Neanderthals, nor that wolves were tamed 100ky ago, and the evidence for Neanderthals not having projectile weapons is ambiguous, IMO.

Julien Riel-Salvatore said...

Anne -
agreed - that's what I meant when I said that biological datasets made in contemporary settings should be used to craft better models of the interaction (biological and behavioral/cultural) between Neanderthals and modern humans.

JJ Anderson said...

I think John Hawks has an excellent blog, but I disagree that the species status of Neandertal is a scientific issue. It’s actually a matter of esthetics and convenience. Just as nature cannot tell us whether Pluto is a “planet” or not, nature cannot tell us if Neandertals are a different species from homo sapiens. How many gene differences make them a different species? It’s an arbitrary decision by us humans. This is additional evidence that the common descent model is true.

The Field Museum in Chicago has a Neandertal and a modern human skeleton right next to each other, and the differences are easy to see. John Hawks is a “lumper”, but I think it is useful to consider Neandertals a separate species. It’s interesting but irrelevant that they have contributed some of their genes to us.

Anne Gilbert said...

Julien, Ken, Luna, and all:

It is, of course, far easier to compare closely related species in "modern" nature, than it is to compare the behavior and habits of fossil hominins/hominids. We know that wolves and coyotes, for example, have very similar habits. It is a surprise to some, but in "undisturbed" conditions where they are relatively unbothered, coyotes can and do form packs. Normally they don't prey on large hoofed animals the way wolves do, but before wolves were reintroduced to Yellowstone, they have been observed running down elk. This exact same behavior has been observed among coyotes which in habit a national park in upstate New York(the favorite food there is white-tailed deer, though). They have the same gestation period, their mating season is roughly the same, etc., etc. I can also tell you, partly from my on purely unscientific observations, that our local gulls, which are considered hybrids, and the only "requirement" for mating, as far as I can tell is, they have to have pink feet.

All these organisms are generalistic in habits, they live in a great many environments, and they generally are alb3e to eat anything biodegradable. I think you can say much the same(if the archaeological evidence can be entirely relied upon) about "modern" humans and more "archaic" forms of Homo. To take Neandertals and "moderns', for example, both were/are generalistic in habits, and though Neandertals tended to live in colder climates than "moderns", they tended, apparently, to use those environments in quite similar ways. If we could start from that, combining it with whatever genetic information we can get out of either earlier Paleolithic "moderns" and/or their "archaic" contempraries, we may begin to get a better idea of how they all interacted, which would really be useful stuff to fill out the human evolutionary story.

Ken said...

Well OK not fully domesticated but they had behaviors that made them useful to hunters (who gave them the entrails and bones) from the beginning, and social adaptations that let them live with humans as one of the 'pack' Mitochondrial DNA research suggests that most domestic dogs have been separate from wolves for at least 100,000 years so we have associated with dogs for an awful long time.

Trinkaus (1995) analyzed patterns of injury in Neandertals and determined that their patterns of injury were highly unusual in comparison to most human groups (including some ancientgroups), and he concluded that Neandertal hunting involved close contact with angry medium-sized ungulates, and that Neandertal technology may have limited them to close range hunting.

Something kept modern humans out of Europe for a long time so it was likely Neanderthals who clearly were more than a match for humans back then. Later they were maybe about equal and that's when the breeding too place.

"Joyce said the best explanation for the variations was that our human ancestors and the archaic species interbred during two periods after the first Homo sapiens had left Africa: the first in the Mediterranean around 60,000 years ago, and the second in eastern Asia about 45,000 years ago"

However the later humans were too much for Neanderthals

Experimental evidence concerning spear use in Neandertals and early modern humans

Human Spear Likely Cause Of Death Of Neandertal

How Neanderthals met a grisly fate: devoured by humans

Morphological Differences in the Parietal Lobes within the Human Genus

"The role of the upper parietal lobule in the recognition and codification of the outer spatial environment and the associated integration between the outer frame and the inner perceptions would seem to indicate that such morphological changes may also have been related to important neurofunctional differences"

Julien Riel-Salvatore said...

James -
this goes back to the question of what we mean by species, and there are several different species concepts that are used in paleoanthropology (as in biology and paleontology), which complicates matters. Of course, classification systems are rarely completely free of preconception and you yes, in many cases, the boundaries between different units in these classifications can be somewhat fuzzy. That does not, however, invalidate the question of whether or not Neanderthals and modern humans should be considered a single or different species. Quite the contrary, it forces researchers to be always more explicit about how much similarity or difference between two organisms is sufficient to classify them differently. The fact that some Neanderthals are physically distinctive from some modern humans is appreciated by everyone involved in paleoanthropological research - the issue is precisely that of trying to determine how much difference is enough, and whether or not that difference is an overall trend, or clustered in certain attributes and/or individuals. In that sense, it's definitely not simply an issue of 'esthetics' but rather one of coming to an agreement on how to approach given problems in paleoanthropology. One can certainly use the notion that Neanderthals were a distinct species as a hypothesis to be tested, but when you simply assume that they are a distinct species without the possibility of changing that opinion, well, you're moving away from a scientific research question.

Julien Riel-Salvatore said...

Anne -
that's a good point. I've often argued that if we start by looking at both Neanderthals and modern humans as first and foremost highly efficient hunter-gatherers (efficiency being suggested by both their longevity and their geographic distribution), the questions we find ourselves grappling with are very different from the ones that dominate paleoanthropology and tend to focus on whether or not the capacity for individual behaviors was present in a species as a whole. I think that people like Jim O'Connell (link to anoutstanding paper of his) have made a very, very good case for this alternative perspective and I do hope it gains some more traction in the discipline.

Anne Gilbert said...

Julien:

Thanks for the reference to the Jim O'Connell paper. I would very much like to read it, although my computer is out of commission at the moment, so I'll have to wait a few days. But that's another story. I should add that much of my thinking about Neandertals and "moderns" has been influenced partly by my anthropology background, and partly by my discovery of how similar some organisms considered separate "species" actually are, even down to gene exchange. I have further come to the conclusion that evolution is a very messy process, and that many people's conceptions of how evolution works, is influenced by preexisting beliefs(mine included, though I really try to see what the scientific evidence actually is).

Leif Ekblad said...

In addition to what Ken already have referenced, there is another issue that makes it unlikely that Neanderthals were very similar to modern humans. Neanderthals apparently lived nearby modern humans for thousands of years, and coexisted with them in Eurasia between perhaps 100,000 years to 30,000 years, and yet there is no sign of hybrid populations as we see in the case of red wolf. There are at most a few isolated examples of possible hybrids. These findings largely disprove the idea that Neanderthal behaved exactly like us.

Julien Riel-Salvatore said...

Ken, Leif -
No one is arguing Neanderthals weren't different - the disagreement is over what that difference means from a biological and behavioral standpoint.

Ken, for wolves, the genetic and morphological evidence are somewhat at odds and show patterns that suggest that accepting a 100kya age for taming is maybe somewhat premature. As for the skeletal robusticity of Neanderthals, there's no question that they engaged in close-contact hunting... what I meant to say about projectile weapons is that there is no evidence that modern humans developed them earlier than Neanderthals (Villa and Soriano 2010, Journal of Anthropological Research). Further, taking a critical look at the data used by some to argue for early AMH projectile weaponry indicates that by those standards at least some Neanderthals pointed implements could have been used as dart tips or even arrowheads (cf. Shea 2006). That being the case, the issue of who killed Shanidar 3 with what appears to have been a projectile weapon remains an open question: we don't have solid dates for that individual, and the estimate of 50kya corresponds to a period during which modern humans are not known in the fossil record of the Zagros. As for the case for AMH eating Neanderthals, the link you provide lists several reasons to take that interpretation with a healthy helping of salt. Lastly, as concerns difference in brain morphology, given the paucity of evidence at hand to discuss this, I'd say there is still much disagreement as to exactly what these might mean and whether we're necessarily seeing population-level trends as opposed to individual variability. Now, again, there is no argument that the morphologically distinct population we call Neanderthals disappeared from the fossil record, and as I indicated in my original post, the new genetic discoveries make looking for explanations behind this process even more interesting... it may well be that it wasn't a case of interspecfici competition as it was a case of competition between distinct groups of hunter-gatherers (see the O'Connell reference above).

Leif - well, that really depends on how you look at the evidence. Morphologically, there is actually quite a bit of evidence that 'classic' Neanderthal traits were not as strongly expressed in the Levant as they were in Europe, and studies that have taken a non-binary (i.e., a specimen is either Neanderthal or modern human) actually have shown that the Levantine hominins stand somewhere between the two morphological extremes, with concomitant implications for their biological relationship to modern humans (e.g., Moncel and Voisin 2006). Again, this is not to say that there weren't differences, but especially in light of Green et al.'s new genetic work, what these morphological differences meant from a biological standpoint is a question that very much has been brought back to the forefront of paleoanthropology.

German Dziebel said...

Nice post. Thank you.

"people need to come to grips with all of the available data, as opposed to considering one line of evidence as trumping all others."

Be careful what you wish for. When I considered "all the evidence," including linguistics and kinship studies (see Dziebel, The Genius of Kinship: The Phenomenon of Human Kinship and the Global Diversity of Kinship Terminologies, 2007), I arrived at the conclusion that humans could NOT have radiated from Africa. By monopolizing human origins research archaeologists/paleoanthropologists and then geneticists, created an impression that humans colonized the Americas relatively late (12-15,000 years ago), while they spread from Africa between 100 and 40K years ago. However, if we look at the levels of linguistic diversity, associated grammatical and morphological structures as well as kinship systems and terminologies it seems likely that humans, in fact, spread from America into the Old World, including Africa. So, what probably happened is that Homo sapiens sapiens was originally a small marginal Neandertal or Asian Homo erectus population that migrated over to America, speciated there and then returned to the Old World and colonized Australia, Europe, Asia and Africa. In this process they replaced Neandertals and African AMH. Woolly mammoths underwent the same migration in and out of America.

What Green et al 2010 reported is the existence of a deep substructure outside of Africa that's older than the putative "earliest" split of humans into Khoe-San and the rest. Green et al's admixture scenario is clearly an artificial explanation, as, first, admixture would've affected both Neandertals and "us," and, second, European populations would have been more affected by this interbreeding than Asian populations, while Papuans wouldn't have been affected at all. Green et al. found traces of an ancient kinship between Neandertals and non-African humans, those traces that have been lost in African humans as they are more derived and maybe more selectively affected than Eurasian humans. This theory predicts that this Neandertal genetic legacy is the strongest in American Indians (not in Green et al.'s sample). Compare, for instance, the high frequencies of shovel-shaped incisors in Neandertals, Asian Homo erectus, modern Asians and, especially, American Indians, and low frequencies thereof in African populations.

We seem to have a cultural bias in favor of "hard" data such as fossils and genes. In reality, only all lines of evidence combined can provide an accurate picture of human evolution and dispersals.

Ken said...

William Calvin has some ideas about projectile predation. While there are actual throwing spears to prove some archaics had them there's nothing like that for Neanderthals. They had a massively strong grip which suggests stabbing while humans had shoulder joint asymmetries, there is the inner ear evidence too.


The moderns maybe did not prey on them except as a target of opportunity, but I still think Neanderthals would have quickly learned to fear and avoid humans and that would limit hybridization, it be vanishingly rare.

The Woof at the Door

Anne Gilbert said...

Julien, Leif, and all:

My feeling about this is, yes, the morphoplogical differences between Neandertals in Western Europe and AMH were there, but how important were they, really? Even 50 kyr ago, they may have been little more than regional variations exptressed morphologically. It doesn't seem to me that, archaeologically speaking, there was much difference, overall, in the way they behaved.
Anne G

terryt said...

Thanks, Julien, for what seems to be the most sensible take I've read on the subject.

"'classic' Neanderthal traits were not as strongly expressed in the Levant as they were in Europe, and studies that have taken a non-binary (i.e., a specimen is either Neanderthal or modern human) actually have shown that the Levantine hominins stand somewhere between the two morphological extremes"

To me that has always been the evidence that Neanderthals and 'modern' humans were not so different after all. And formation of hybrids a most likely occurrence.

"the morphoplogical differences between Neandertals in Western Europe and AMH were there"

And the differences between breeds of dog are even greater, but most have no trouble forming fertile offspring. In fact often more fertile than either parent breed. Admittedly some will point out that the differences are a product of human selective breeding but differences in other species are often a product of 'natural, selection. Not too different in effect.

"I have further come to the conclusion that evolution is a very messy process, and that many people's conceptions of how evolution works, is influenced by preexisting beliefs"

I'm sure that is so. I argued that point exactly in my series of essays at remotecentral.

CamArchGrad said...

I'm wondering what it would be like to go back to my old alma mater, Cambridge (the heart of "Out of Africa) and look at them now. As a multiregionalist it was a lonely existence, and they were so damn sure that it was true, though I do remember Paul Mellars cornering Mirtha Larh and grilling her as to whether they were absolutely sure that it was true.

Milford Wolpoff (who else) had a great diagram where he lined up all the circum Mediterranean skulls from Djeble Irhoud to La Ferrasie via Skul/Quafzeh. His point was to look at each relative to it's neighbor and from that you could see that La ferrasie & Djeble irhoud were end members of a continuous spectrum of variation.

One of the things I think will come out of more genetic work is it's not so much that La Chapelle & Klasies River Mouth got it on, but rather there was continous gene flow between geographically adjacent groups of homonids and so genes could be passed on and selected without the original "hosts" ever meeting in time and space.

A good test for this would be to compare the Croatian populations with the French and Levantine populations. It should fall neatly between the two. Likewise Omo 1&2 should be closer to Djeble Irhoud than to Border cave.

Re: North American antecedents. I don't think that New world antecedent is very likely. There is far too little evidence of any sort of human presence in North America prior to the LGM (~18 000 kya) However northeast Asia has a fabulous sequence fossils and the correct time depth for such linguistic and kinship diversity. It's not a stretch to imagine the New World inheriting that as function of migration from N.E. Asia (while the NE Asian diversity was wiped out during the Holocene).

Anne Gilbert said...

CamArchGrad:

Your conclusions about some of the conclusions that you came to (and I did) are very pertinent. For myself, I tend to consider both the OoA people and the multiregional group more or less half right. IOW, there's no doubt in my mind that the "modern" human morph originated in Africa at about the time the genetic studies say it did. There seems to be a fair amount of archaeological and other evidence to back this up. Where the multiregional people are right, howver, is not to assume that each little group of humans was totally separate; adjacent groups, whether they were "archaic"(for lack of a better word here) or "modern", each recognized the other somehow as basically human, and they would, from time to time, bump into one another. I think this is probably what happened, with Neandertals and others. It wasn't necessarily peaceful all the time, but it was probably peaceful enough, from time to time and place to place, for genes to get exchanged. The question of whether one considers N's to have been a different species then depends largely on how many important similarities or dissimilarities one sees between the two groups. Western European N's seem to have been the most "different" morphologically, yet Erik Trinkaus and others, even here, sees evidence of gene exchange.

And I do agree with you, that taking anything close to a "multiregionalist" perspective at one time felt awfully lonely and "far out". One of the reasons it has taken so long for me to even come up with a way to write my Great Medieval Science Fiction Masterpiece With Neandertals was precisely for those reasons. I didn't even want to mention the name of the "prehistoric people" I was writing about at one time, though there were always a few people who were receptive. I still keep a lot of this close to my chest, but now it's for personal reason, and mostly with some family members, and not for "scientific" ones. In any case, I think Neandertals may finally be getting respectable, which is something they have long deserved, but have not gotten.


Sorry for the long post,
Anne G

terryt said...

"One of the things I think will come out of more genetic work is it's not so much that La Chapelle & Klasies River Mouth got it on, but rather there was continous gene flow between geographically adjacent groups of homonids and so genes could be passed on and selected without the original 'hosts' ever meeting in time and space".

Right on!

"However northeast Asia has a fabulous sequence fossils and the correct time depth for such linguistic and kinship diversity. It's not a stretch to imagine the New World inheriting that as function of migration from N.E. Asia (while the NE Asian diversity was wiped out during the Holocene)".

Well put. I tried to explain something similar to german once before, but couldn't put it so well.

"As a multiregionalist it was a lonely existence, and they were so damn sure that it was true"

And yet Dienekes can say something to the effect the 'fashionable view of Neanderthal admixture'. If it's fashionable it has only become so in the last two weeks! And many are still fighting a desperate rearguard action.

Anne Gilbert said...

Terryt:

It's really weird. Some of the strongest OoA adherents still keep going on and on about how they're basically a lonely, unaccepted minority. Not so much now, but go back about 5 years and you'll see what I mean.
Anne G

German Dziebel said...

"I don't think that New world antecedent is very likely..."

I don't mean to hijack the discussion, but you missed my point.

From an archaeological/paleontological perspective only, yes, if we, first, ASSUME that the absence of evidence of human presence in the Americas beyond 15K is the evidence of absence of humans in that part of the world, and then again ASSUME that linguistic and cultural diversity in NE Asia was wiped out during Holocene, we can say that "New World antecedents are unlikely."
But these are assumptions that only cloud our perception of reality.

What we KNOW is much more modest: 1) NE Asia or Beringia has no clues for the origin of the earliest New World-wide technological complex ("Clovis"); 2) Clovis technologies moved from south to north and not from north to south in North America; 3) humans were present in the Americas south of the ice shield (Monte Verde, etc.). The rest are speculations. It's funny how little archaeology can definitively tell us about the past, and what it tells us is completely different from the myths we ourselves extracted from archaeological findings.

Archaeology in the Americas has been compromised by the decades of bickering about the antiquity of man, hence the overall picture is fuzzy and controversial. But even if the paucity of signs of human activity in this continent are "objective," the situation can be explained by demography and adaptation: population size in the Americas prior to Clovis times was low and those populations relied on "soft" technologies, hence, naturally, the visibility of the "human behavioral package" is low, too. Without the yawning lack of data characteristic of the Americas, this applies to the whole Asia-Pacific region, as contrasted with Europe and Africa. Once again, low-density foraging populations "express" their antiquity not in stone tools but in linguistic and cultural diversity and complexity.

As for the argument of linguistic and cultural extinction in NE Asia in the Holocene, it's flawed on several levels: 1) there's no evidence for this massive extinction whatsoever; 2) we would expect to find a remnant of former diversity in some refuge area such as the Altai mountains but we don't; the only two refugia we can think of are Papua New Guinea and the Caucasus and they are way outside of NE Asia; 3) a similar extinction needs to have happened in Africa as it's also culturally and linguistically homogeneous (comp. 140 language stocks in the Americas vs. 20 in Africa), but then the extinction argument becomes utterly ad hoc; 4) Holocene extinctions in NE Asia, if they happened, would only add another area with high linguistic and cultural diversity outside of Africa; 5) culturally and linguistically American Indians show a very wide range of similarities that go beyond NE Asia (it's Papua New Guinea, Australia, Caucasus, parts of Africa, Europe). This is unexpected from a population that supposedly branched off from a recent localized source.

Once again, my theory is based on the interpretation of ALL lines of evidence taken together, not on one or two preferred sources of prehistoric revelation.

Andrew Oh-Willeke said...

"Something kept modern humans out of Europe for a long time so it was likely Neanderthals who clearly were more than a match for humans back then. Later they were maybe about equal and that's when the breeding too place."

Maybe. But, climate is certainly equally or more plausible. The case that deserts and bodies of water created major barriers to human arrival until climate change allowed them to burst into Europe about 40,000-50,000 years ago has considerable support in the physical record, and the very low population density of Neanderthals, based upon the limited information we have on their effective population size from DNA evidence does make a hominin barrier as the major factor seem very plausible.

terryt said...

"if we, first, ASSUME that the absence of evidence of human presence in the Americas beyond 15K is the evidence of absence of humans in that part of the world"

If humans were present in the New World before 15k they would be the only humans ever to have left no evidence of their presence, either through the extinction of game animals or an increase of environmental destruction though fire. So It's very unlikely himan presence in America dates back very far, unless there were so few of them to be unable to form a large population. Possible if inbreeding was a factor in their survival.

"NE Asia or Beringia has no clues for the origin of the earliest New World-wide technological complex ('Clovis')"

I'm quite happy to accept that Clovis is an indigenous American invention.

"population size in the Americas prior to Clovis times was low"

Extremely unlikely when considering what we know of other species moving into new environments. Admittedly the population may remain low for a few generations before expanding, but only for a few generations. They either then expand greatly in numbers or become extinct.

"culturally and linguistically American Indians show a very wide range of similarities that go beyond NE Asia (it's Papua New Guinea, Australia, Caucasus, parts of Africa, Europe). This is unexpected from a population that supposedly branched off from a recent localized source".

Interesting that these cultural similarities occur in populations that have been isolated for a particularly long period. Suggests to me that they preserve an ancient social organisation that has been wiped out by more recent expansions through more accessible regions of the world.

German Dziebel said...

"If humans were present in the New World before 15k they would be the only humans ever to have left no evidence of their presence, either through the extinction of game animals or an increase of environmental destruction though fire. So It's very unlikely himan presence in America dates back very far, unless there were so few of them to be unable to form a large population. Possible if inbreeding was a factor in their survival."

"Extremely unlikely when considering what we know of other species moving into new environments. Admittedly the population may remain low for a few generations before expanding, but only for a few generations. They either then expand greatly in numbers or become extinct."

I would be very careful about assigning what is "likely" and what is "unlikely" (especially, "extremely unlikely") in deep prehistory. I just follow where the evidence takes me. Humans is a miner's canary in any evolutionary research because we have way more genetic, paleontological and cultural data from humans than from any other species living or extant species. If the data pressures us to consider the "unlikely," then this is what we should be doing.

Regarding extinctions, Africa is a classic continent in which extinctions happened to a limited degree, that's why we still have all those big animals there. And hominins lived there for millions of years and humans for at least 45K. So, there's no strict correlation between extinction and the presence of humans. In the Americas, Late Pleistocene sites showing massive extinctions of megafauna aren't associated with human tools or remains.

"I'm quite happy to accept that Clovis is an indigenous American invention. "

Good. This means archaeology hasn't provided us with evidence for any technological continuity between Siberia and America (microblades found all over Siberia, in other parts of Eurasia and in Africa at least since 20K ybp are only found in some northern areas of North America) which could be used as an argument for a migration from Siberia to America. It's a "hung jury." Geneticists, however, assume that this evidence exists, hence their dates for the peopling of the Americas are presented as somehow consistent with archaeology.

German Dziebel said...

(contd.)


"Interesting that these cultural similarities occur in populations that have been isolated for a particularly long period. Suggests to me that they preserve an ancient social organisation that has been wiped out by more recent expansions through more accessible regions of the world."

Sure, but you can't expect this kind of survival in populations that are only 12K years old and derive from a local Siberian source. If the consensus was such that American Indians peopled America during the very first wave of expansion across the Old World, I probably would be quite content. But then we would run into the problem: why there's no archaeological evidence of human presence in the Americas between 12 and 45-50K if it exists in Asia and Australia? And why wouldn't this ancient social organization and linguistic diversity be preserved in Africa supposedly filled with ancient genetic lineages (say, L0, L1, L2 in mtDNA and A and B in Y-DNA) not preserved in any out of Africa migrants. The survival of those ancient lineages in Sub-Saharan Africa means that those populations also were in isolation (otherwise, they would've been replaced by more recent lineages and lost without a trace). So, your argument, Terry, falls apart. It would've made sense if, for instance, Africa was linguistically and culturally diverse, had ancient patterns of social organization, then Eurasia lacked them but attested to them in refugia with clear ties to Africa and then some (!) of those cultural attributes would resurface in the Americas. But again this is not the case. In fact the opposite is true: the languages of the Caucasus show very startling similarities to American Indian languages but not to African languages. Same for Australia and Papua New Guinea. But, for instance, Khoisan clicks aren't found anywhere outside of Africa. Hence, they emerged in Africa after humans came there. It's so easy, Terry.

German Dziebel said...

"Possible if inbreeding was a factor in their survival."

Kinship theory does depict the evolution of human mating patterns from "symmetrical prescriptive marital alliance," which involves the repetition of cross-cousin marriage from generation to generation (attested in the Americas and in parts of Asia and Australasia but not in Africa or Europe) to "complex and open marital networks." African and European populations all fall into the latter, derived category. So, what may have happened is the relaxation of some selective constraints on the genetics of small populations and the corresponding increase in heterozygosity as humans populated Europe and Africa. This fits very well with the key population genetic finding that ancestral human population size must have been small. American Indians preserved this ancestral population structure the best among living populations.

terryt said...

"Regarding extinctions, Africa is a classic continent in which extinctions happened to a limited degree, that's why we still have all those big animals there".

I understand that that is not true. According to Bjorn Kurten's book, 'The Age of Mammals', almost 40% of the different genera of large animals had become extinct by 60,000 years ago, and most were extinct long before then. The African extinctions he lists from before 60k include three-toed horses, a giant deer, an antlered giraffe (sort of sivatherium), giant baboons, sabertooth and scimitar-toothed cats, a bear, many types of pig and various kinds of elephants, hyenas, antelope and buffalo.

"So, there's no strict correlation between extinction and the presence of humans".

Kurten does admit the extinctions extended over a long period but his claim of them having been completed by 60,000 years ago fits the idea of modern humans appearing in Africa by that date surprisingly well.

"In the Americas, Late Pleistocene sites showing massive extinctions of megafauna aren't associated with human tools or remains".

Some are, and the coincidence of timing is remarkable. And humans need not have actually been responsible for killing the last mammoth for them to have been responsible for mammoth extinction. And megafauna extinctions are not the only evidence. We usually see a huge increase in fire, and it's regular re-occurrence, with the arrival of humans.

"But then we would run into the problem: why there's no archaeological evidence of human presence in the Americas between 12 and 45-50K if it exists in Asia and Australia?"

Because there were no people in America between 12 and 45-50K?

"Kinship theory does depict the evolution of human mating patterns from 'symmetrical prescriptive marital alliance,' which involves the repetition of cross-cousin marriage from generation to generation (attested in the Americas and in parts of Asia and Australasia but not in Africa or Europe) to 'complex and open marital networks.' African and European populations all fall into the latter, derived category".

Perhaps the 'complex and open marital networks' developed and spread more recently than 12,000 years ago?

German Dziebel said...

Terry,

I suggest reading "American Megafaunal Extinctions at the End of the Pleistocene," by Gary Haynes, in which the usual interpretation of extinctions as caused by human activity is heavily criticized from the point of view of actual data. The same concerns African extinctions: the mere chronological overlap is no proof of anything. Humans probably showed all kinds of behavior toward megafauna, from hunting to scavenging to avoiding it altogether. The Overkill hypothesis is a very outdated and again mythical way of looking at Pleistocene extinctions.

BTW, prior to 60K, who was killing African megafauna? Anatomically modern humans? With what tools?

""But then we would run into the problem: why there's no archaeological evidence of human presence in the Americas between 12 and 45-50K if it exists in Asia and Australia?"

Because there were no people in America between 12 and 45-50K?"

You missed my point. I posed this question in the context of a supposition, based on a more moderate interpretation of linguistic and cultural evidence (and I'm not the one who advances it), that humans were in America by 50K and arrived there as part of the very first coastal migration. The mistake you're making is providing a categorical answer instead of playing with assumptions and predictions without trying to "announce" what happened.

The best way to prove that there were no humans in America between at 40K is to find 1) a large number of sites in the Americas between 12 ans 20K; 2) describe them in terms of adaptational and lithic patterns and then identify their antecedents in Siberia. Same for Clovis if you believe in Clovis-I. Otherwise, as in the case of extinctions, there's simply no data to support a theory.

"We usually see a huge increase in fire, and it's regular re-occurrence, with the arrival of humans."

Hearths have been identified in a number of pre-Clovis sites. And if humans originated in America, then their non-invasive adaptation, which affected both the style of tools and the lifestyle, must have preceded the more aggressive one which developed only as humans colonized the Old World and encountered other hominids. So using Old World humans as a model for their possible antecedent in the New World is putting the cart before the horse.

"Perhaps the 'complex and open marital networks' developed and spread more recently than 12,000 years ago?"

It's possible and if this is the case than of course this aspect of kinship theory can't be used for deep historical inferences. But I wouldn't assume it to obtain a carte blanche to ignore cultural and linguistic evidence altogether. The out of Africa theory of human dispersls is based on a panmictic assumption for the ancestral population, while this assumption is borne out only by modern European and Sub-Saharan African populations engaged in "complex ad open marital networks." The mating patterns in lots of human populations outside of Africa are clearly structured along kinship lines ("symmetrical prescriptive alliance," "asymmetrical prescriptive alliance," etc.), and these arrangements are considered characteristic of the earliest human kinship structure by virtually all anthropologists. The Green et al. study confirms that early human populations were subdivided, so we have a nice match here.

CamArchGrad said...

GD,

I think you misunderstand the nature of the extinction i was positing. Humans did not go extinct in East Asia, but diversity was lost. One only has to look at State history in E asia to see the massive and wholesale replacement of populations via migration, and replacement of a settled agricultural population.

Where are the Jurchen's or Khitain? Or the Xiongu? incorporated into Han ethinicity.

You see a similar pattern in Europe and the NE, where Etruscan, Sumerian, and Minoan all disappeared thousands of years ago. Linguistic/ethnic extinction happens and has happened extremely frequently in history and has accelerated in the past 5000 years as state level society's have spread across the globe. The examples I mention are known because someone bothered to record them. Most of the time the record is silent.

Moreover,diversity does not equal time depth. In a geographically diverse areas human society's will rapidly fragment linguistically and ethnically(with pre industrial communication). However, as societies grow they incorporated and homogenize the surrounding populations.

A good example of this is polynesia, where in 1000 years a population spread from a single source to cover most of the pacific. Linguistic/cultural differences between Fijian, Hawaiian, and Maori are quite apparent (but not as strong as they could have been given the outstanding ability of Polynesian seafarer's, and the limited time before European re-integration.)

The America's are another example of this but on a far larger scale over a much longer time period, hermetically sealed for 15,000 years they were "caught" at the ideal time by anthropologists. Long enough to have massive diversity in language and culture, but not long enough to have massive empires homogenize large sections of the region (no Romans or Mongols).

Finally a note on Pre-Clovis archaeology. The good evidence for pre-clovis falls into a tight time range of 14kya - 12kya and is a thin scattering of sites consistent with a colonizing population(Manis, Monte Verde, Meadowcroft, Paisley caves, Guitarro).

Before that, we have the most unhuman population ever. They did not bury their dead, they did not butcher or kill anything, they left no traces (no wood exploitation (unlike Kalambo Falls/Clacton), no fire, no art(unlike Europe or Australia), no plant exploitation, no complex stone tools, no human fossils, no
trade, no jewelry, never inhabited caves, never inhabited the paleo-Mississippi/ or the shores of Lake Bonneville, never visited Rancho Labrea, nor Old Crow. It should be noted that after 12,500, there is immense and undeniable evidence of all of the above.

It's not a problem of archaeological visibility either. A quick scan though most Quaternary literature points out thousands of sites, with millions of fossils from the Old Crow Basin to the Pampa's of Argentina, with outstanding sites like rancho labrea, the sinkholes of Florida, Natural Trap cave Wyoming, the loess of Mississippi and many,many others.

Where's our Hauh ter, Djeble Irhoud, Casablanca? Our Kromddrai, Border cave, or Klasies River Mouth, our Olduvia, Omo, Olorgellasie or Narmada, our Arago, Boxgrove, Bocher Taktit, Grimaldi,Atapuerca or Petralona our Choukoutien, Dali, Xiaochiangliang, Maba Our Dmanisi, Shanidar,Skhul,Ksar Akil our, Kara-Kamar, Ngangdong-Solo, Dyukhtai, Kow swamp, Malakunanja, Lake Mungo or Bobongara?

It's why we have to rely on archaeology. If we use other methods we get the wrong answer.

terryt said...

"the mere chronological overlap is no proof of anything".

Stunning coincidence though, isn't it. And throughout the world.

German Dziebel said...

"I think you misunderstand the nature of the extinction i was positing. Humans did not go extinct in East Asia, but diversity was lost. One only has to look at State history in E asia to see the massive and wholesale replacement of populations via migration, and replacement of a settled agricultural population."

I understood your argument correctly. And even after you elaborated on it it seems flawed to me. America also experienced wholesale population replacements tied to agriculture and early state formation. Historic isolates went extinct under the pressure from their non-agricultural neighbors. In addition, we know for a fact that lots of languages and populations went extinct as a result of recent European colonization (think of California, Texas in North America to mention just a few areas), and they have never been recorded. Nothing of this sort happened in Siberia. Amazonia still has tribes unknown to the "European man." Nothing of this sort is true of Europe. Amerindian diversity is unparalleled in its both actual and potential states.

And it's not only diversity that matters. Niger-Congo has more languages than any other language family but they all look and sound similar because they diverged some 5000 years ago. Amerindian languages are diverse on the stock level.

"The America's are another example of this but on a far larger scale over a much longer time period, hermetically sealed for 15,000 years they were "caught" at the ideal time by anthropologists. Long enough to have massive diversity in language and culture..."

This is a myth that you're trying to perpetuate. You can't possibly evolve 140 language stocks in a matter of 15K years. Recently, the Ket language in Siberia was shown to be related to Na-Dene. It's a connection some 10K years old. What about all the other 139 stocks found south of what used to be the glaciated areas?

"It's why we have to rely on archaeology. If we use other methods we get the wrong answer."

No. We should only rely on a cross-disciplinary synthesis. Archaeology can only pose questions. Like your question "where is our Mungo Lake"? I don't know. It can't provide answers. We don't have a clue when and how America was colonized.

"Before that, we have the most unhuman population ever. They did not bury their dead, they did not butcher or kill anything, they left no traces (no wood exploitation (unlike Kalambo Falls/Clacton), no fire, no art(unlike Europe or Australia), no plant exploitation, no complex stone tools, no human fossils, no
trade, no jewelry, never inhabited caves, never inhabited the paleo-Mississippi/ or the shores of Lake Bonneville, never visited Rancho Labrea, nor Old Crow. It should be noted that after 12,500, there is immense and undeniable evidence of all of the above."

You assume this means the absence of humans. Well, linguistics, culture and kinship theory beg to differ. A hundred years ago Ales Hrdlicka would swear on the eyes of his mother that humans were in America for no more than 5,000 years. At the same time, linguists were painstakingly working trying to make sense of the phenomenal diversity posed by American Indian languages. The situation repeats itself. Too bad, archaeologists never studied linguistics and they continue to hold on to some mythical ideas of how humans colonized the New World. We need to learn to think about prehistory not only in terms of what people left behind in garbage pits and graveyards but also in terms of what they passed down to future generations (language, culture, kinship).

"no human fossils"

We barely have any chimp fossils and up until a couple of years ago we had absolutely none. Should we try and derive bonobos from the Pygmies and Common chimps from the Maasai while we are looking for more "hard" evidence to prove chimp antiquity?

German Dziebel said...

""the mere chronological overlap is no proof of anything".

Stunning coincidence though, isn't it. And throughout the world."

I don't think it answers our question of who came from where, though. Say, in America, population size was low until 12K and adaptation was non-invasive. Then population increased, new technologies appeared, this contributed to animal extinctions. Humans entered Africa, SE Asia and Australia at 50K after having traversed the whole globe, their population increased, their adaptation became invasive as they had to fight off adversities, and so they started contributing to animal extinctions right away. By the time of the colonization of New Zealand and Madagaskar, they already became well-equipped, populous and aggressive. Even more so by 1870s when European colonizers almost eliminated the last surviving species of megafauna in North America, the bison.

CamArchGrad said...

GD,

We actually have very strong evidence, of how and when North America was colonized, it is only because it does not support your case, that you choose to ignore it. In all parts of the eur-asia-african landmass, there is strong evidence habitation for many tens of thousands of years. In North America - Nothing before the waning of the LGM (18 kya).

"We barely have any chimp fossils and up until a couple of years ago we had absolutely none. Should we try and derive bonobos from the Pygmies and Common chimps from the Maasai while we are looking for more "hard" evidence to prove chimp antiquity?"


We have a huge hominoid fossil record stretching back to the Eocene, so the fossil ancestry of the Great Apes was never a question. Pan, is a rain-forest dweller, which is underrepresented in the fossil record due to taphonomic processes. Hominids are not confined to the rain forest and inhabit such fossil traps as caves, riverine environments, volcanic landscapes.

Moreover, you're postulating that despite existing in the America's and have an evolutionary development in the America's (from who? Homo erectus? ergaster?) there are no fossils or archaeological sites despite the massive abundance of other fossils.

"You can't possibly evolve 140 language stocks in a matter of 15K years."

Why not? Who'd been around for 15k years to test this?

"Nothing of this sort happened in Siberia"

Except for the Russian colonization. In an area like N.E. Asia where populations were never high and geographic barriers strong, the impact of a massive state level society aggressively expanding and displacing the former inhabitants would be catastrophic (and the Russians were not particularly nice colonizers).

State formation in the Americas was interrupted. Small groups of people could remain "untouched" as it were in places like the Pacific Coast. Had Europeans come 500 years later the picture would have been very different.

Finally there is the reverse problem with genetics. Why is Africa presumably a late stage colonization by AMH out of the Americas far more genetically diverse than the Americas? It is an interesting question as to why the area that has the longest fossil/genetic record is not the most diverse in language or Kinship, but to ascribe the difference to an archaeologically and genetically invisible people is ridiculous.

Alex Hrdlika was falsified by the hard evidence of Clovis not the soft evidence Linguistics & Kinship.

CamArchGrad said...

Another note, before I leave this horse,

Further researching in New world languages reveals that diversity seems to have been concentrated in areas where there were complex hunter-gatherers (Mainly along the pacific coast(California/BC), and areas immediately inland) (Campbell 1997 p.104) were present.

In the east of North America, south of Boreal forest
agriculture already seems to have reduced the number of languages present in comparison to the west coast. Likely the diversity would have been reduced even more by these autochthonous processes, had not the Spanish arrived.

The implication is that europe had a much greater linguistic diversity in the Mesolithic, that was subsequently lost during the Neolithic and the metallic periods after.

German Dziebel said...

"We actually have very strong evidence, of how and when North America was colonized, it is only because it does not support your case, that you choose to ignore it. In all parts of the eur-asia-african landmass, there is strong evidence habitation for many tens of thousands of years. In North America - Nothing before the waning of the LGM (18 kya)."

Hmm. Then why did Dennis Stanford suggest a trans-Atlantic route for the origin of Clovis? Isn't because there's no evidence for Clovis origins in Siberia? I don't believe in the Solutrean-Clovis link but if archaeologists go as far as suggesting something like this it means they are desperate to explain what a traditional Beringian model doesn't.

And you again assume that the absence of evidence is the evidence of absence. Population size and adaptation are better predictors of the density of archaeological record than age.

"Pan, is a rain-forest dweller, which is underrepresented in the fossil record due to taphonomic processes."

A similar taphonomic context elsewhere didn't prevent us from finding Homo floresiensis. In any case, your assumption that antiquity always results in lots of fossil finds is falsified. Another assumption that you seem to make, albeit less explicitly, namely that if there were ancient signs of human presence in America they would have already been found, is falsified by the history of Australian archaeology. Up until early 1980s people believed Australia was colonized 10K years ago. Now, it's 40K and counting.

"We have a huge hominoid fossil record stretching back to the Eocene, so the fossil ancestry of the Great Apes was never a question."

As recent research demonstrates, chimps are not our direct ancestors but rather a collateral branch. The fossil ancestry of chimps was never in question because... we never fought with them for the land. Our obsession with the recency of American Indians (clearly attested by Ales Hrdlicka's attitude), which flies in the face everything that we know about their languages and cultures, is related to land competition in the Americas between the colonizers and the colonized. American Indians were declared archaeologically recent and imminently "vanishing" (ultimately because biologically unfit) - a typical colonization story. There's nothing in the archaeological record that justifies this approach.

"Moreover, you're postulating that despite existing in the America's and have an evolutionary development in the America's (from who? Homo erectus? ergaster?)"

The human story may have been similar to that of woolly mammoths: originated in Asia, migrated into the Americas, speciated there, migrated back into Asia, replaced their old relatives - the Siberian mammoth. http://www.cell.com/current-biology/abstract/S0960-9822%2808%2900970-6

German Dziebel said...

(contd.)

"Alex Hrdlicka was falsified by the hard evidence of Clovis not the soft evidence Linguistics & Kinship."

Well, if you know the history, it took a cowboy to do an archeologist's job. If archaeologists have partnered with linguists and ethnologists from the very beginning and haven't dismissed their findings, just the way you continue to do, as irrelevant to the problem of the antiquity of man in America, we would've ended up with more grants to do "pre-Clovis" archaeology regularly, systematically and professionally without waiting for some random finds like a Clovis point or a Kennewick man to turn the tables around. And people like Fiedel, instead of going through Dillehay's dirty laundry, should do something more constructive: say, find pre-Clovis in Siberia if he believes it was there. As of now, the only fluted projectile point in Northeast Asia is only some 8K old (Uptar site).

German Dziebel said...

(contd.)

I suggest that humans evolved from a small population of Neanderthals (now attested in South Siberia) or Homo erectus, migrated to the Americas, speciated there (we need isolation to speciate, don't we?) and then, now equipped with fully developed language and culture, migrated back into the Old World to replace all pre-existing hominids. Alvah Hicks over at www.humanoriginsolved.com resurrected Ameghino's idea of human evolution from New World monkeys. I don't endorse it but it's worth mentioning.

""You can't possibly evolve 140 language stocks in a matter of 15K years."

Why not? Who'd been around for 15k years to test this?"

Think about it this way. A typical language family is 3-5,000 years old. Sometimes, we can establish genetic connections between languages that have been separated for 8-10,000 years (Na-Dene and Ket, Afroasiatic languages). Now think how many extant language stocks - assuming they are all somehow related - you can reduce to one proto-language in 15,000 years? If the migration to the America was massive and derived from a large geographic source harboring different language stocks, then of course we could say that most of its attested linguistic diversity was transplanted from Siberia. But this will make geneticists cringe because there's not enough genetic diversity in the Americas to postulate a very large founding population. Also, why would we need to model a linguistic situation in Late Pleistocene Siberia on a linguistic situation found in the Americas in order to explain the latter? You can strive for "scientific rigor" but only as long as the outcome makes sense.

"Finally there is the reverse problem with genetics. Why is Africa presumably a late stage colonization by AMH out of the Americas far more genetically diverse than the Americas?"

In genetics, there's a natural connection between allele diversity and effective population size. This all fits together nicely: large human populations in Africa and Europe (and we have reasons to believe that hominid populations in these regions were larger than hominid populations in Asia in Lower to Mid Pleistocene as well) left a behind a greater density of archeological finds. But the systematic presence of modern human behavioral traits in the archaeological record (the Upper Paleolithic and the Late Stone Age) begins only at 40K in both Africa and Europe. Pretty much simultaneously with South Siberia, although Kara-Bom (43K) looks like is older than anything in Western Europe and North Africa (Dabban). At 35K we have the Hofmeyer skull in South Africa that clusters not with modern African populations but with Eurasian populations. The evidence for a migration into Africa couldn't be better. We're missing only some 25K of archaeological attestations in America to make the full connection. And we have thousands of years ahead of us to find them. If it took Dillehay 20 years to prove Monte-Verde (and it's only 2K years older than Clovis), it may take a while for serious archaeologists to fight their the way through Clovis-I bureaucracy and match the 40K benchmark for the emergence of modern human behavior in the Old World. Again, archaeologists could speed up the process by learning from the other disciplines and then abandoning the European Upper Paleolithic as a measuring stick for how modern human behavior should express itself in the archaeological record in the New World.

terryt said...

"Say, in America, population size was low until 12K and adaptation was non-invasive".

Very unlikely. Most species are not 'non-invasive'. They tend to expand rapidly until they reach the balance point with resources and predation pressure. The American population would only have remained low if thye were subject to a fair bit of predation.

German Dziebel said...

"Very unlikely. Most species are not 'non-invasive'. They tend to expand rapidly until they reach the balance point with resources and predation pressure."

Good. It means the invasive aspects of their adaptation will eventually be detected. The archaeological record in the Americas is likely incomplete.

terryt said...

"It means the invasive aspects of their adaptation will eventually be detected".

It should already be detected. I can easily accept a small population in America from an early date. But not a widespread population. It would have to have been confined to just a small region. Perhaps we are still to detect the invasive evidence for that region.

German Dziebel said...

"It should already be detected. I can easily accept a small population in America from an early date. But not a widespread population. It would have to have been confined to just a small region. Perhaps we are still to detect the invasive evidence for that region."

Speculations, Terry. We have pre-Clovis sites and candidates from all over America. Maybe archaeology is simply not the discipline to ground our understanding of prehistory.