search this blog

Showing posts with label Afanasevo. Show all posts
Showing posts with label Afanasevo. Show all posts

Friday, January 21, 2022

Yamnaya is from Europe, but it's really from Asia


I was about to post a comment under a new preprint at bioRxiv, but the comment section isn't there anymore. Hopefully, this is just a temporary glitch.

The preprint in question is titled Reconstructing the spatiotemporal patterns of admixture during the European Holocene using a novel genomic dating method [LINK]. It's co-authored by Harvard/Broad MIT scientist Nick Patterson who occasionally comments at this blog.

My impression is that the authors see the people associated with the Yamnaya culture as Asians who simply used "far" Eastern Europe as a springboard to expand into other parts of Europe.

If so, they're dead wrong.

There are at least three arguments why the Yamnaya population should be seen as quintessentially European:

- its home was initially and overwhelmingly the Pontic-Caspian steppe, which is entirely located within the present-day borders of Europe

- Yamnaya genomes are clearly different from those of older populations native to nearby parts of Asia, and, in fact, these differences show a very strong correlation with the present-day borders between Europe and Asia

- the Yamnaya people weren't a new population in Europe by any stretch, but must have been overwhelmingly derived from the very similar Eneolithic peoples of the Pontic-Caspian steppe and/or the nearby forest steppe, both of which are located in Eastern Europe.

And yet, this is what the preprint claims:

The beginning of the Bronze Age was a period of major cultural and demographic change in Eurasia, accompanied by the spread of Yamnaya Steppe Pastoralist-related ancestry from Pontic-Caspian steppes into Europe and South Asia (16).

In fact, what really happened at this time was that Yamnaya steppe pastoralist-related ancestry spread from Eastern Europe to other parts of Europe, as well as to Central and West Asia.

The preprint does eventually explain that present-day South Asians derive their Yamnaya-related ancestry from a later eastward expansion of the European Corded Ware culture (CWC), but it completely ignores the fact that the Afanasievo culture was the result of the initial eastward expansion from Europe to Asia. That is, the ancestors of the Afanasievo people were recent migrants from the Pontic-Caspian steppe to Central Asia and Siberia.

There's also this:

Over the following millennium, the Yamnaya-derived groups of the Corded Ware Complex (CWC) and Bell Beaker complex (BBC) cultures brought Steppe pastoralist-related ancestry to Europe.

Seriously? Both the CWC and BBC, just like the Yamnaya culture, were from Europe. In fact, as per above, the descendants of the CWC expanded into Asia.

And this:

The second major migration occurred when populations associated with the Yamnaya culture in the Pontic-Caspian steppe expanded to central and western Europe from far eastern Europe.

The authors basically admit here that Yamnaya came from Eastern Europe, but they call it "far" Eastern Europe. Perhaps they know something I don't, but as things stand, there's no evidence that Yamnaya came from "far" Eastern Europe. In fact, the emerging consensus based on ancient DNA, including pre-publication data, is that Yamnaya may have originated in what is now Ukraine. In my opinion, Ukraine isn't located in "far" Eastern Europe, but more or less in the middle of it.

Inexplicably, this is what they say about the genetic origins of the Yamnaya and Afanasievo peoples:

These groups were likely the result of a genetic admixture between the descendants of EHG-related groups and CHG-related groups associated with the first farmers from Iran (8, 22, 36).

...

Thus, we combined all early Steppe pastoralist individuals in one group to obtain a more precise estimate for the genetic formation of proto-Yamnaya of ~4,400 to 4,000 BCE (Figure 2). These dates are noteworthy as they pre-date the archeological evidence by more than a millennium (37) and have important implications for understanding the origin of proto-Pontic Caspian cultures and their spread to Europe and South Asia.

Not really.

Like I said, the Yamnaya population was overwhelmingly derived from the Eneolithic peoples of the Eastern European steppe and/or forest steppe. And these Yamnaya-like Eneolithic peoples were spread out across a vast area of Eastern Europe by at least ~4,500 BCE. Some of their genomes have been available for several years, and many more are on the way.

It is possible that the Yamnaya and Afanasievo genotype formed in 4,400-4,000 BCE, but if so, then this was due to mixing between the Eneolithic steppe peoples and nearby European farmers. That's because the difference between the Yamnaya and Eneolithic steppe genotypes is minor (~15%) European farmer admixture in the former.

The really interesting puzzle is exactly where and when the peculiar Eneolithic steppe genotype came into being. Any ideas Dr Patterson?

See also...

Matters of geography

Understanding the Eneolithic steppe

Friday, July 26, 2019

Afanasievo people may well have been proto-Tocharian speakers (Ning et al. 2019)


Update 17/08/2019: A surprising twist to the Shirenzigou nomads story

...

During the Early Bronze Age, around 2,900 BCE, a population associated with the Yamnaya archeological culture migrated from the Pontic-Caspian steppe in Eastern Europe deep into Asia, as far as the Minusinsk Basin in South Siberia.

This rapid, long-range expansion was likely to have been the first significant migration of a Yamnaya-related group far to the east of the Ural Mountains, and it resulted in the formation of the Afanasievo archeological culture (see here).

The appearance of Tocharian languages in the Tarim Basin, in what is now western China, is often associated with the Afanasievo culture, mainly because of the confirmed presence of European-related populations in the Tarim Basin during the Bronze Age, as well as the likely highly divergent position of the Tocharian node in the Indo-European language phylogeny.

But the Afanasievo people were separated by considerable distance in space and time from the Tocharians, and can't yet be reliably linked to them with archeological or genetic data. So even though the inference that the former are linguistically ancestral to the latter is quite plausible, it's far from certain.

However, thanks to a new paper at Current Biology by Ning et al., at least we now know that a population with significant Yamnaya/Afanasievo-related ancestry was living in the eastern Tian Shan Mountains just a few hundred years before Tocharian languages were attested nearby [LINK]. Below is the paper summary, emphasis is mine:

Recent studies of early Bronze Age human genomes revealed a massive population expansion by individuals-related to the Yamnaya culture, from the Pontic Caspian steppe into Western and Eastern Eurasia, likely accompanied by the spread of Indo-European languages [1, 2, 3, 4, 5]. The south eastern extent of this migration is currently not known. Modern-day human populations from the Xinjiang region in northwestern China show a complex population history, with genetic links to both Eastern and Western Eurasia [6, 7, 8, 9, 10]. However, due to the lack of ancient genomic data, it remains unclear which source populations contributed to the Xinjiang population and what was the timing and the number of admixture events. Here, we report the first genome-wide data of 10 ancient individuals from northeastern Xinjiang. They are dated to around 2,200 years ago and were found at the Iron Age Shirenzigou site. We find them to be already genetically admixed between Eastern and Western Eurasians. We also find that the majority of the East Eurasian ancestry in the Shirenzigou individuals is-related to northeastern Asian populations, while the West Eurasian ancestry is best presented by ∼20% to 80% Yamnaya-like ancestry. Our data thus suggest a Western Eurasian steppe origin for at least part of the ancient Xinjiang population. Our findings furthermore support a Yamnaya-related origin for the now extinct Tocharian languages in the Tarim Basin, in southern Xinjiang.


Ning et al., Ancient Genomes Reveal Yamnaya-Related Ancestry and a Potential Source of Indo-European Speakers in Iron Age Tianshan, Current Biology, July 25, 2019, DOI: https://doi.org/10.1016/j.cub.2019.06.044

See also...

It was always going to be this way

The mystery of the Sintashta people

Late PIE ground zero now obvious; location of PIE homeland still uncertain, but...