A new ancient DNA preprint, this time using the sequence of a 34,000-year-old sample from Northeastern Mongolia. The preprint is Denisovan ancestry and population history of early East Asians:
We present analyses of the genome of a ~34,000-year-old hominin skull cap discovered in the Salkhit Valley in North East Mongolia. We show that this individual was a female member of a modern human population that, following the split between East and West Eurasians, experienced substantial gene flow from West Eurasians. Both she and a 40,000-year-old individual from Tianyuan outside Beijing carried genomic segments of Denisovan ancestry. These segments derive from the same Denisovan admixture event(s) that contributed to present-day mainland Asians but are distinct from the Denisovan DNA segments in present-day Papuans and Aboriginal Australians.
There are two major points in this preprint. First, as noted in the title, this adds weight to the inference that there were multiple admixtures between “Denisovan” populations and the peoples of south and east Eurasia. I put Denisovan in quotations because there is more and more evidence now that this was a diverse and variegated lineage of humans, not a simple classification such as Neanderthals, who often seem to have been closely related due to periodic population bottlenecks. This individual carries segments similar to the Altai Denisovan, and something different from the segments in the Papuans.
I think the second major aspect here is east-west gene flow in Eurasia in a bidirectional sense. It seems more and more likely that the “Ancient North Eurasians” (ANE) reflect two dynamics. First, the rapid expansion of an ancient West Eurasian branch of humans pushing up through the Near East and into Central Asia, and then Siberia, very early. Second, the assimilation and admixture with a minority element of incipient East Asian populations pushing up from the south. Though the trend was patchy and uneven, eventually the East Asian ancestral component kept increasing, until you have “Neo-Siberian” modern populations which are overwhelmingly East Asian.
Why the difference? As with Denisovans, I think the answer is a function of biogeography. Though West Eurasians had an easier “straight shot,” East Asians had a much larger reservoir population near at hand to the south over the late Pleistocene. Over time this resulted in a difference, whereby Siberian populations become more and more East Asians, with relatively little influx of West Eurasian genes until the Russian colonization.
This seems to provide a good explanation of why Uralic, Turkic, Mongolic, and many other northeast Asian language families share characteristics with western Eurasian language families but are spoken by mostly genetically East Asian populations.
Interesting how they place ANS phylogenetically closer to Goyet than to the Kosteni-Sunghir group. If this is true beyond both being early mixed east-west Eurasians; that is if both of their west Eurasian ancestries came from the same source to the exclusion of Kostenki, Sunghir and Gravettians then this definitely looks like a new developement.
I’m guessing these East Eurasians didnt carry EDAR. Is there evidence of WSHG/ANS ancestry in any known population? Also what did the ANS people look like? Does it still hold true that Yana was 1/4 East Eurasian overall?
Also if ANS was y P and 1/4 East Eurasian whereas Malta was y R and 100% ANE (not sure how much East Eurasian is in ANE). So how did the “East Eurasian component” get shedded in between?
Also you last paragraph makes sense. Unfortunate but makes sense.
But I don’t think we’re talking about Siberia proper.
WSHG was about 80% West Eurasian and don’t forget the later Indo-European expansion to Siberia. Turko-Mongols changed the demographics until Russia brought them back to the state they were in for most of history.
How do native Americans figure into this? For the most part they maintained the ANE character of their paternal gene pool and the ENA of their maternal gene pool.
Do you also think India had a similar situation to Siberia? With West Eurasians (y H and mt U/R) colonizing the region first but proxmity to an area with a large East Asian resovoir population increased the ENA character until the Mesolithic and IE invasions reversed it?
@Jatt Scythian
Where did you get the idea of East Asian mother and West Eurasian father fantasy of yours regarding ANS? Both Malta and Yana had West Eurasian MtDNA. It is actually their Y lineage that may trace to East Eurasians ultimately.
Neither Russians nor South Asians have anything to do with Scythians other than a vague linguistic affiliation in the latter case and virtually nothing in the former case. You should just get over it.
I never said that about ANS. I said that about Native Americans.
Y P might be East Eurasian I agree. But it was already assimilated by ANE. Also I’m curious what the original ANE y dna was in that case. E might have been Eurasian initially (I don’t care either way) but it was assimilated into the African gene pool early on.
Also my username is tongue in cheek. Other than that go away Hector.
Endorse pretty closely to the whole of this post, excellent weaving the Salkhit specimen into the wider human story.
I remarked on this paper elsewhere that it makes the interactions in East Eurasia make more sense.
Like, in Melinda Yang and Qiaomei Fu’s adna “synthesis of findings” paper from 2018 – https://www.cell.com/trends/genetics/fulltext/S0168-9525(17)30210-X – there was a model where we had East Eurasian Tianyuan like population living at pretty high latitude in East Asia, but not really having much without geneflow *from* and instead only *to* the local ANE populations, and there’s implied to be this fairly hard boundary between East Asian and ANE populations, with some one way geneflow (https://imgur.com/a/9u9DNiY).
But I think this makes it make more sense, in that you had some form of bi-directional admixture between ANE and high latitude East Eurasian populations.
Then the reason we don’t see much of this today is more because the present day high latitude East Eurasian populations just don’t take that much admixture from earlier ones, and were mostly from replacements out of more southern refugia that didn’t receive ANE ancestry (as you note/imply!). This does away with unexplained one directional admixture.
One slight thing I’d modify is that maybe I’d guess there was a bit of back-and-forth on East Eurasian vs ANE ancestry until last after 16kya. AfontovaGora3 with lots of ANE is still pretty far east and north up until 16,130-15,749 BP, and the WSHG Neolithic era samples noted above too.
The power of biogeography *was* really important here but I’d add to that, I’d guess this raw biogeography probably got helped along a bit in its later phases by technological developments – I’m thinking of pottery neolithic / “broad spectrum revolution” and then also overflow from millet neolithic among NE Asian populations, both of which probably helped expand food supply and so relative population size of north expanding East Asian ancestry, and really enable quite a bit more of a dominant expansion in the Siberian zone than pure biogeography alone would have taken it to.
(Final note, also we can note ANE may have also had its own southern refugia after a fashion – there are indications in adna that peoples living in the Western “Turan” zone would have been pretty rich in ANE. So wasn’t totally without reservoir/refugia population).