tag:blogger.com,1999:blog-7785493.post53605639668439654..comments2024-01-04T04:11:55.717+02:00Comments on Dienekes’ Anthropology Blog: Ancient mtDNA from Denisova CaveDienekeshttp://www.blogger.com/profile/02082684850093948970noreply@blogger.comBlogger69125tag:blogger.com,1999:blog-7785493.post-58985865784901761442014-09-28T23:39:09.794+03:002014-09-28T23:39:09.794+03:00"Assuming that the Y-DNA haplogroup R existed..."Assuming that the Y-DNA haplogroup R existed so early in time" <br /><br />That occurred to me as soon as I'd posted my comment. It is impossible that it would be R although some sort of CF may be remotely possible. terrythttps://www.blogger.com/profile/17327062321100035888noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-57509047239746810442014-09-28T15:33:54.522+03:002014-09-28T15:33:54.522+03:00Right Maju, now it looks like we are in presence o...Right Maju, now it looks like we are in presence of contamination, as suggested by a commenter in that thread. But I still don't get why the guys from Max Planck institute uploaded a human Y chromosome labeling it as Altai Neanderthal.Vincenthttps://www.blogger.com/profile/13096774136070274675noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-65740906667503334352014-09-24T07:31:39.858+03:002014-09-24T07:31:39.858+03:00"I don't know how reliable this is, but a..."I don't know how reliable this is, but a Denisovan specimen may have had a human father with Y-DNA R" <br /><br />Neanderthal or Denisovan, I see no reason why it should be impossible. Interbreeding almost certainly went in both directions. terrythttps://www.blogger.com/profile/17327062321100035888noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-38679514100425711122014-09-24T00:05:41.681+03:002014-09-24T00:05:41.681+03:00@Vincent: sounds intriguing but someone should dou...@Vincent: sounds intriguing but someone should double and even triple check that claim because it sounds most unlikely. And as it's said "exceptional claims require exceptional evidence". <br /><br />The Denisova Cave Neanderthal toe was found in a layer deeper than the one of the "Denisovan" (H. heidelbergensis) fingers, so it must be older than 50 Ka BP, probably 60-70 Ka BP. <br /><br />Assuming that the Y-DNA haplogroup R existed so early in time (what is quite dubious even for someone like me, who tends to favor old chronologies), the signature of possible H. sapiens admixture in this specimen is maybe not impossible but would be very weak in any case. I mean: it is known that admixed populations are pulled upwards in ML trees and that is indeed the case of the Altai Neanderthal in the autosomal tree approximation (but then again this could just mean that this population was more ancestrally diverged relative to known European Neanderthals, not necessarily implying admixture) but the displacement is very mild, what would allow at most a minimal H. sapiens (or H. heidelbergensis) admixture. That would mean that if the alleged finding is true the male lineage had been interbreeding with unmixed female Neanderthals for many generations. Not impossible but, sincerely, a highly unlikely scenario, and one that would push the Y-DNA R ancestor even further back in time. <br /><br />So yeah: triple check it, please, because it looks a very weird scenario for many reasons. Majuhttps://www.blogger.com/profile/12369840391933337204noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-62388388709939603122014-09-22T02:12:17.645+03:002014-09-22T02:12:17.645+03:00Correction: it was a Neanderthal living in the sam...Correction: it was a Neanderthal living in the same cave as the Denisova hominin, not a Denisovan properVincenthttps://www.blogger.com/profile/13096774136070274675noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-67064310815063845592014-09-22T01:20:44.537+03:002014-09-22T01:20:44.537+03:00I don't know how reliable this is, but a Denis...I don't know how reliable this is, but a Denisovan specimen may have had a human father with Y-DNA R http://www.reddit.com/r/genetics/comments/2gt9d2/denisova_cave_neanderthal_was_ydna_haplogroup_r/Vincenthttps://www.blogger.com/profile/13096774136070274675noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-57608599732523897322010-04-20T10:32:13.371+03:002010-04-20T10:32:13.371+03:00"But that would simply place the Denisova fos..."But that would simply place the Denisova fossil as even more ancient"...<br /><br />I have already said what I see here: an H. erectus lineage from the first migration into Eurasia. <br /><br />"So that in turn would place the migration back into Africa some time before the Acheulean"...<br /><br />Why should there be any migration back into Africa? Where's the archaeology to support it?<br /><br />"Which actually makes sense, because the Acheulean didn't make it to Central, East or SE Asia although H. erectus was certainly present through most of that region".<br /><br />I was not clearly aware of that detail but actually it supports the idea of this lineage being H. erectus from the first OoA wave of all. <br /><br />In brief, the sequence of OoA migrations is:<br /><br />1. H. erectus with chopper industry c. 2 Ma ago -> Denisova<br /><br />2. H. ergaster with Acheulean c. 1 Ma ago -> Neanderthal<br /><br />3. H. sapiens (MSA, 130-70 Ka ago). <br /><br />And there is absolutely no need for any backmigration to Africa, which is not justified archaeologically. What there is need is for a radical revision of the the molecular clock.Majuhttps://www.blogger.com/profile/12369840391933337204noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-45219875391050134782010-04-20T07:44:13.353+03:002010-04-20T07:44:13.353+03:00"As I see it, what supports an old divergence..."As I see it, what supports an old divergence tree (of c. 1 million years) between our species and Neanderthals is (1) the Acheulean migration out of Africa, pretty well documented and with older known dates of c. 900,000 BP in South Iberia and (2) the very marked morphological differences between the two species". <br /><br />But that would simply place the Denisova fossil as even more ancient, and still the oldest mtDNA we have extracted. So that in turn would place the migration back into Africa some time before the Acheulean and after the original H. erectus emergence from Africa. Which actually makes sense, because the Acheulean didn't make it to Central, East or SE Asia although H. erectus was certainly present through most of that region.terrythttps://www.blogger.com/profile/17327062321100035888noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-84774536400314234242010-04-19T06:53:04.972+03:002010-04-19T06:53:04.972+03:00"To me this suggests that modern humans are a..."To me this suggests that modern humans are actually a product of a migration INTO Africa (from Asia) after both the Denisova population (?) and the Neanderthals had branched off. Then modern humans came back out". <br /><br />It's a possibility and one that is very fashionable these days it seems. However there's no archaeological evidence whatsoever supporting that hypothesis, though admittedly there is also a blank of evidence in Africa to support the in situ evolution of our species from H. erectus. <br /><br />As I see it, what supports an old divergence tree (of c. 1 million years) between our species and Neanderthals is (1) the Acheulean migration out of Africa, pretty well documented and with <a href="http://leherensuge.blogspot.com/2009/09/acheulean-much-older-than-thought-in.html" rel="nofollow">older known dates</a> of c. 900,000 BP in South Iberia and (2) the very marked morphological differences between the two species. <br /><br />Sincerely I fail to see how in just 200,000 or even less years the two species could have diverged so much. There is only one point of convergence: large brains but that is clearly a product of evolutionary pressure/trend on a path already taken by the whole genus Homo long before. Otherwise the two species are markedly different, always within the specifics of the genus as a whole. H. sapiens has been diverging for maybe as long and nowhere, not even in the most remote corner nor the most isolated population, it has been able to accumulate so many differences (not even a fraction). <br /><br />And for me this finding of Denisova, which I strongly suspect bearing a pre-Acheulean H. erectus lineage, whatever the species, actually does nothing but add evidence in favor of this thesis. <br /><br />But of course the definitive evidence can only come from archaeology, filling the blank we have in the evolution of our species between H. erectus/ergaster and H. rhodesiensis/sapiens, the same that Atapuerca has filled in the gap between the former and Neanderthals. <br /><br />So far this has been elusive but Africa is huge and has not the same archaeological research density as does Europe. However the indirect evidence in form of industrial typologies, I understand, rather supports separate evolutionary processes in Europe (towards Neanderthal) and in Africa (towards H. sapiens). <br /><br />Emotionally I'd might prefer that the roots of humankind would be at Atapuerca, just a few kilometers from where I live and where my roots are but the data does not seem to support that. And the Denisova hominin's phylogeny does not either.Majuhttps://www.blogger.com/profile/12369840391933337204noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-83613175064471207792010-04-19T06:06:08.465+03:002010-04-19T06:06:08.465+03:00"that actually might just show there were not..."that actually might just show there were not any species at all" <br /><br />I'm reasonably convinced that there has only been one 'species' of Homo since Homo erectus, and that all 'subspecies' since that time have been able to form fertile hybrids. What we see in the fossil record is little different from what we see today with the various human geographic varieties. <br /><br />"I'm a heretic because I'm highly skeptic of the potential of the MC as we know it". <br /><br />Regardless of the 'actual' dates the 'relative' dates are still relevant. Either way we have the Denisova fossil branching off the line leading to modern humans before the line leading to Neanderthals does. To me this suggests that modern humans are actually a product of a migration INTO Africa (from Asia) after both the Denisova population (?) and the Neanderthals had branched off. Then modern humans came back out.terrythttps://www.blogger.com/profile/17327062321100035888noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-36481491747853247962010-04-18T03:35:52.850+03:002010-04-18T03:35:52.850+03:00hehe so asia has an archaic erectus contemporary n...hehe so asia has an archaic erectus contemporary not from china to showcase now, enriching the human lineage with at least one other species, that actually might just show there were not any species at all:) whats new? lolonixhttps://www.blogger.com/profile/03063983314231972946noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-75058380317356401322010-03-31T22:38:38.888+03:002010-03-31T22:38:38.888+03:00PConroy: what that article and possibly others see...PConroy: what that article and possibly others seem to suggest is that we have to review all the archaeology only because of some MC estimate. And that's simply what MC fans have been suggesting all the time at other levels: when archaeology and MC estimates don't match (what happens way too often) it <i>must</i> be because the archaeological record is wrong or misinterpreted. <br /><br />But the fact is that, with all its shortcomings, archaeology and C14 are still much more solid, more accurate or simply better than whatever the molecular clock esotherisms can offer.<br /><br />The Denisova "problem" is easily solved by adjusting the MC in accordance with what we know from the archaeological record: Neanderthals diverging c. 1 mill. or 900,000 years ago (and not just 700-300 Ka) and the early colonization of Eurasia by H. erectus happening c. 2-1.8 Ma ago. <br /><br />But, well, I know: I'm a heretic because I'm highly skeptic of the potential of the MC as we know it.Majuhttps://www.blogger.com/profile/12369840391933337204noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-6018913400302204252010-03-31T21:54:07.554+03:002010-03-31T21:54:07.554+03:00Here a great post by "The Atavism" blog ...Here a great post by "The Atavism" blog on this:<br />http://theatavism.blogspot.com/2010/03/does-forty-thousand-year-old-finger.html<br /><br />Especially a nice diagram explaining how Denisova could be a Neanderthal:<br />http://img.photobucket.com/albums/v387/science_boy/tubetree_corrected-1.pngpconroyhttps://www.blogger.com/profile/10312469574812832771noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-72613669321171446822010-03-31T20:53:14.506+03:002010-03-31T20:53:14.506+03:00"More recent research suggests they diverged ..."More recent research suggests they diverged much later, less than 1 million years ago"...<br /><br />And <a href="http://www.plosgenetics.org/article/info%3Adoi%2F10.1371%2Fjournal.pgen.1000057;jsessionid=D7B9BB616D3AD7A4DB0EAF4C1D8FC03E" rel="nofollow">even more recent research</a> instead suggests an older date again, which could be more or less coincident with the one proposed by Stone in 2001. <br /><br />Caswell 2008 proposes a divergence time of at least 1.3 million years ago but she also suggests that the formation of the Congo river c. 1.5-2 million years ago is a more likely reference, because it is this river what keeps chimpanzees and bonobos separated. <br /><br />I discussed Caswell's most interesting paper <a href="http://leherensuge.blogspot.com/2008/04/new-paper-ofn-chimpanzee-and-bonobo.html" rel="nofollow">here</a> and is one of the reasons why I think that one of the most basic assumptions when calculating molecular clock hypothetical ages, the Homo-Pan divergence date, is radically wrong, being the real one at least 15% larger (the difference between 7 and 8 million years) or even as much as 50% larger (the difference between 5 and 10 million years). <br /><br />"Chimpanzees and bonobos are quite capable of forming fertile offspring".<br /><br />I missed this claim (from Terry, I imagine). Are they really? Do we know of any real case? It's the first time ever I read such claim and I have never heard of an hybrid Pan, much less a fertile one.Majuhttps://www.blogger.com/profile/12369840391933337204noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-38708504453043304212010-03-31T19:06:41.052+03:002010-03-31T19:06:41.052+03:00'The dotted line indicates the chimpanzee-bono...<i>'The dotted line indicates the chimpanzee-bonobo divergence time (1.8 million years) estimated with the Pt?1 haplogroup'.</i><br /><br />More recent research suggests they diverged much later, less than 1 million years ago:<br /><br />http://mbe.oxfordjournals.org/cgi/content/abstract/22/2/297<br /><br /><i>Chimpanzees and bonobos are quite capable of forming fertile offspring.</i><br /><br />That is why common chimpanzees and bonobos should be classified as subspecies of a single chimpanzee species.<br /><br />If one day a fertile human-chimpanzee hybrid is produced, humans should also be included in the chimpanzee species as its subspecies (see Jared Diamond's "The Third Chimpanzee: The Evolution and Future of the Human Animal"). The same is true for the other hominina lineages. Of course, we can use homo rather than chimpanzee as the name of the species which would include all hominini (the tribe that comprises all hominina and pan). If gorillas can produce fertile offspring with humans and chimpanzees, they also should be included as a subsepcies of the same species with humans and chimpanzees.Onur Dincerhttps://www.blogger.com/profile/05041378853428912894noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-32667130387417826482010-03-31T19:06:41.053+03:002010-03-31T19:06:41.053+03:00This comment has been removed by the author.Onur Dincerhttps://www.blogger.com/profile/05041378853428912894noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-87891985171848261082010-03-31T10:46:17.174+03:002010-03-31T10:46:17.174+03:00Glad that you bother providing quotes, Terry. They...Glad that you bother providing quotes, Terry. They are not what you said but well... <br /><br />"Straight hair is very rare in Australian Aborigines and Papuans"<br /><br />And pre-admixture Ainu (NE Asians). And Australia and Papua are not SEA. What we were discussing there and elsewhere (here at Dienekes' for example) was the existence (per Karafet) of a Paleolithic divide at Wallace Line. <br /><br />Whatever the case, you are assuming too many things from mere phenotypes, which we know can vary wildly with minimal genetic/epigenetic variations. <br /><br />And also you are wildly off topic. <br /><br />...<br /><br />"Just because the human/Neandertal/Denisova haplogroups separated less than one million years ago in no way automatically means they were unable to form fertile offspring".<br /><br />It does not mean that, agreed. But we know now that there was no effective admixture between Neanderthal and H. sapiens, so it's reasonable to hypothesize that there was no effective admixture either between Neanderthals and Eurasian H. erectus.<br /><br />Even if this hypothesis is wrong, from what we know (which admittedly is not much) we must still deal with Denisova as a different population in principle. <br /><br />You can't just assume that the less likely option is right just because it might be right. It might also be wrong.Majuhttps://www.blogger.com/profile/12369840391933337204noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-37766985671203409402010-03-31T05:56:13.925+03:002010-03-31T05:56:13.925+03:00"But we don't know that. It's a big I..."But we don't know that. It's a big IF with nothing to support it". <br /><br />It's often claimed that a single group of chimpanzees contain greater haplogroup diversity than does the whole of humanity. Therefore, obviously, just 100,000 years is insufficient to separate chimpanzee species. Just because the human/Neandertal/Denisova haplogroups separated less than one million years ago in no way automatically means they were unable to form fertile offspring. For example: <br /><br />http://www.pnas.org/content/99/1/43.figures-only?cited-by=yes&legid=pnas;99/1/43<br /><br />From the article: 'The dotted line indicates the chimpanzee-bonobo divergence time (1.8 million years) estimated with the Pt?1 haplogroup'. Chimpanzees and bonobos are quite capable of forming fertile offspring. <br /><br />So if the three human species did not produce offspring it is unlikely to have been because of genetic incompatability, but a result of cultural factors.terrythttps://www.blogger.com/profile/17327062321100035888noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-68138061056305413682010-03-31T05:47:37.331+03:002010-03-31T05:47:37.331+03:00"Terry, did you mean this part of one of Maju..."Terry, did you mean this part of one of Maju's comments in the 'Major East-West divide in Indonesian Y chromosomes' thread?" <br /><br />No. His main claims are in the 'Indonesian Y-haps mostly Paleolithic', or something similar. His comments there include: <br /><br />"For me the data evidences that there is now enough variability to imagine every possible scenario". <br /><br />So let's look at this hypothesis. One hundred thousand years ago all of Africa and Eurasia south of about 50 degrees N was occupied by humans, or closely related species. All modern humans are believed to descend from just the African subset of this population. <br /><br />But it's extremely unlikely that the OoA contained a representative sample of the contemporary African genetic variation. Therefore modern humans descend from just a subset of a subset. Is it really credible to believe they were an extremely varied population? more varied even than are modern Africans? <br /><br />The vast majority of Africans today have tightly curly hair. Even moderately curly hair is uncommon, and where it is found it is most likely a product of migration in from Eurasia. So either something very strange happened in Africa after the OoA, or the hypothesis of 'enough variability to imagine every possible scenario' is wrong. <br /><br />Other related comments he made there: <br /><br />"A lot of 'Mongoloids' have curly hair (Tibet, Amazonia, etc.) It's somewhat atypical but not a definitory trait". <br /><br />To which I'd point out that you have to really look for it, and it is quite possibly a result of migration in from elesewhere, or a pre-Mongoloid survival. <br /><br />Concerning the pronounced eyefold: <br /><br />"Epicanthic fold. A trait that is not totally absent in other populations (Khoisan, North Europeans, etc.) nor universally present among East Asians, much less Native Americans". <br /><br />Concerning yellowish skin: <br /><br />"This trait must have coalesced (founder effect?) early in the human dispersal process because the known pigmentation traits of East Asians seem to arise then (ref- Coop'09)". <br /><br />And: <br /><br />"I say that such traits are flesh and were probably widespread before Neolithic. ... but the patterns of the derived East Asian MC1R haplotype do suggest that these traits are old, very old". <br /><br />But the East Asian suite of characteristics cannot be early Upper Paleolithic in SE Asia. Straight hair is very rare in Australian Aborigines and Papuans, so the East Asian suite of characteristics must have arrived in SE Asia after these people had passed through. Even in Polynesians the suite is not strongly represented. In fact it's only marginally more pronounced in Indonesia, and probably immigrant there. So what are are we left with?terrythttps://www.blogger.com/profile/17327062321100035888noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-75926711387774405692010-03-30T18:29:22.309+03:002010-03-30T18:29:22.309+03:00"It was the closest thing I was able to find ..."It was the closest thing I was able to find in your comments to Terry's description".<br /><br />I know you have good intentions but better let him do his homework: he often misreads (twists, deforms) what I say in extreme ways, what makes discussion kind of difficult because you have to insist once and again in what exactly you meant (or even said word by word).Majuhttps://www.blogger.com/profile/12369840391933337204noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-28706376739526723692010-03-30T16:59:34.194+03:002010-03-30T16:59:34.194+03:00But we don't know that. It's a big IF with...<i>But we don't know that. It's a big IF with nothing to support it. <br /></i><br /><br />I know that it is a speculation. I was just evaluating the necessary implications of that speculation if it is confirmed one day. <br /><br /><i>All species began as "subspecies". I don't understand what's the point here.</i><br /><br />Actually, it seems clear to me that these three Homo lineages diverged enough to be classified as different species or subspecies. <br /><br />The real issue is the one I evaluated in my previous statement: whether these three diverged lineages always remained as subspecies or turned into different species in the course of time.<br /><br /><i>Also I don't see how my quote above resembles what Terry said.<br /></i><br /><br />It was the closest thing I was able to find in your comments to Terry's description.Onur Dincerhttps://www.blogger.com/profile/05041378853428912894noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-84950720316548570732010-03-30T16:25:08.926+03:002010-03-30T16:25:08.926+03:00"If anatomically modern humans, neanderthals ..."If anatomically modern humans, neanderthals and the lineage of the X-Woman could produce fertile offspring from sexual intercouse with each other, they should be considered members of a single species".<br /><br />But we don't know that. It's a big IF with nothing to support it. <br /><br />"And if each of the three separated and diverged from each other for hundreds of thousands of years, they should also be considered subspecies of that single species".<br /><br />All species began as "subspecies". I don't understand what's the point here. <br /><br />...<br /><br />Also I don't see how my quote above resembles what Terry said.Majuhttps://www.blogger.com/profile/12369840391933337204noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-38687818677022271532010-03-30T16:12:58.209+03:002010-03-30T16:12:58.209+03:00Who says that?
I. If anatomically modern humans, ...<i>Who says that?</i><br /><br />I. If anatomically modern humans, neanderthals and the lineage of the X-Woman could produce fertile offspring from sexual intercouse with each other, they should be considered members of a single species. And if each of the three separated and diverged from each other for hundreds of thousands of years, they should also be considered subspecies of that single species.Onur Dincerhttps://www.blogger.com/profile/05041378853428912894noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-72484138623159612882010-03-30T15:54:52.365+03:002010-03-30T15:54:52.365+03:00Terry, did you mean this part of one of Maju's...Terry, did you mean this part of one of Maju's comments in the "Major East-West divide in Indonesian Y chromosomes" thread?<br /><br /><br /><i>However the limited fossil data does suggest a more "Australoid" (or just "archaic") morphology in SE Asia in general (but also in all East Asia) before Neolithic, so we have what may be two (largely) different issues: genetics and phenotype. <br /><br />On the other hand, Australian fossils don't seem clearly "Australoid" either before a recent timeframe (see P. Brown's Australian page), the most archetypally AA skull is that of Roonka, which is about 7000 years old. <br /><br />So I suspect it's about time we begin considering morphology not strictly attached to genetics or ancestry. At least I do try to keep some distance from morphology when analyzing all this data because otherwise I'd go not just "hyper-recentist" but even believer in recent arrival from Mars, as there are no clear precusors for the Mongoloid type (there are not even brachi/mesocephalic Paleolithic skulls almost anywhere!, except maybe Minatogawa, but Brown says he's not Mongoloid either). <br /><br />So I'd either argue for nutrition, recent social selection for those phenotypes or wild epigenetics, rather than recent replacement from nowhere.</i>Onur Dincerhttps://www.blogger.com/profile/05041378853428912894noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-370138074042885552010-03-30T15:52:54.112+03:002010-03-30T15:52:54.112+03:00This comment has been removed by the author.Onur Dincerhttps://www.blogger.com/profile/05041378853428912894noreply@blogger.com