Monday, December 18, 2017

Corded Ware as an offshoot of Hungarian Yamnaya (Anthony 2017)

David W. Anthony has just posted a new paper at his page titled Archaeology and Language: Why Archaeologists Care about the Indo-European Problem (see here).

It's not only an interesting discussion about why the search for the Indo-European homeland is still such a big deal, but also a useful, almost up to date, summary of the fascinating stuff that ancient DNA has revealed about the genetic history of Europe, with a special focus on the origin of the Corded Ware people, who are generally accepted to be the first Indo-European-speaking population of Northern Europe.

Now, I say it's an almost up to date summary, because Anthony seems fairly certain that the Corded Ware people were descendants of the Yamnaya people, rather than just their close relatives. He uses archaeological and ancient DNA data to argue that Yamnaya migrants moved from the North Pontic steppe to the eastern Carpathian Basin (present-day Hungary), and then onto what is now southern Poland to give rise to the proto-Corded Ware population.

I probably would've said this was a highly plausible scenario before I saw the ancient DNA results from the latest preprint of Mathieson et al. 2017, an ancient genomics paper in the works focusing on Southeastern Europe (see here). But now that I've seen those results, I feel that Anthony's proposal might be outdated.

One of the samples in that preprint is from a pre-Yamnaya Eneolithic burial on the northern edge of North Pontic steppe, in what is now eastern Ukraine, labeled Ukraine_Eneolithic I6561. This individual not only strongly resembles the Corded Ware people in terms of genome-wide genetic structure, but also belongs to Y-haplogroup R1a-M417, which is a paternal marker probably no older than the Eneolithic and intimately associated with the Corded Ware expansion. Currently, as far as I can see, he's by far the most likely candidate in the ancient DNA record to belong to a proto-Corded Ware population.

Keep in mind also that not a single instance of R1a-M417 has yet been found among a wide range of prehistoric individuals from the Carpathian Basin. On the other hand, Olalde et al. 2017 (see here) did manage to catch one Early Bronze Age (EBA) Bell Beaker from the region belonging to R1b-Z2103, which is the paternal marker currently most strongly associated with Yamnaya.

Below is a map of Central and Eastern Europe ca. 3000-2000 BCE from Anthony's paper, edited by me to show the burial location of Ukraine_Eneolithic I6561. If we assume that his descendants or close relatives were the proto-Corded Ware population, then looking at this map, it seems unlikely to me that they would've taken the Carpathian Basin route before expanding into Northern Europe. Rather, I'd say that they would've fanned out across the north directly from the steppe, perhaps along those northward-pointing river valleys? And I suspect that they may have still been a pre-Yamnaya group as they migrated out of the steppe, just as Yamnaya was forming somewhere to the east.

But hey, Anthony might be right, and I might be way off. Indeed, perhaps Anthony based his theory, to an extent, on soon to be published Yamnaya samples from the Carpathian Basin? If such genomes have been sequenced, and at least one belongs to R1a-M417, then it's game over as far as the origin of the Corded Ware people is concerned, and I'll welcome the surprise.

See also...

Early Baltic Corded Ware form a genetic clade with Yamnaya, but...

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

Friday, December 15, 2017

Watch the red arrows naysayers

Here's a map from yesterday's presentation by Italian archaeologist Massimo Vidale at the MPI-SHH Jena Cross Roads conference on South Asia. He was focusing on the skeletal remains from the protohistoric, and likely early Indo-Aryan, cemeteries at Udegram and Gogdara in the Swat Valley, modern-day Pakistan. Source: Twitter.

And this is my own map from back in August (see here) summarizing what ancient DNA (both published and otherwise...nudge, nudge) is telling us about the early Indo-European, including Indo-Aryan, expansions across Eurasia.

Remarkably similar, aren't they? And obviously I'm not just talking about the use of ellipses and red arrows by the authors of both maps (probably a coincidence, but perhaps not if Prof. Vidale reads this blog).

Keep in mind also that last year Prof. Vidale sent samples from the Swat Valley cemeteries to the ancient DNA lab at Harvard for testing and analysis (see here). So if these samples yielded endogenous DNA (wink, wink), then he probably knew the results when he drew up his map.

See also...

Indian confirmation bias

The beast among Y-haplogroups

Descendants of ancient European (fair?) maidens in Central Asia's highlands

Friday, December 1, 2017

Descendants of ancient European (fair?) maidens in Central Asia's highlands

Several South Central Asian populations have a reputation for producing individuals who look surprisingly European, even the lighter shade sort of European from Eastern and Northern Europe. This is especially true of the Pamiri Tajiks, and that's unlikely to be a coincidence, because these people probably do harbor a lot of ancient Eastern European ancestry.

My own estimates, using various ancestry modeling methods, suggest that Pamiri Tajiks derive ~50% of their genome-wide genetic ancestry from populations closely related to, and probably derived from, Eneolithic/Early Bronze Age pastoralists from the Pontic-Caspian steppe of Eastern Europe, such as the Sredny Stog and Yamnaya peoples. Below is a simple Admixture graph using the mostly Yamnaya-derived Iron Age Sarmatians from Pokrovka, Russia, in far Eastern Europe, to illustrate the point. Note that Sarmatians were East Iranic-speakers, which is what Pamiri Tajiks are. The relevant graph file is available here.

But, some of you might retort, this is all just statistical smoke and mirrors, and what it really shows is that these so called Europeans came from Central Asia or even India.

Not so, because my models can't be twisted any which way, and they have strong support from uniparental marker data.

Many South Central Asian groups, and especially Indo-European-speakers, like the Tajiks, show moderate to high frequencies of two Y-chromosome haplogroups typical of Bronze Age Eastern Europeans: R1a-M417 and R1b-M269. This is old news to the regular visitors here and its implications are obvious, so if you still think that these haplogroups expanded from South Central Asia to Eastern Europe, rather than the other way around, then please update yourself (for some pointers, see here and here).

And now, courtesy of Peng et al. 2017, we also have a much better understanding of ancient European influence on the maternal gene pool of Pamiri groups (see here). The paper doesn't specifically cover the topic of European admixture in South Central Asia, but it nevertheless demonstrates it unequivocally.

Below are a couple of phylogenetic trees from the paper featuring a wide range of mitochondrial DNA (mtDNA) sequences shared between Europeans and Central and South Asians; quite a few of these lineages are rooted in Eastern Europe, as shown by both modern-day and ancient DNA, so they strongly imply gene flow, and indeed considerable maternal gene flow, from Eastern Europe deep into Asia.

Worthy of note are the lineages belonging to such relatively young (likely post-Neolithic) haplogroups as U5a1a1, U5a1d2b, U5a2a1, and U5b2a1, all of which have already been found in ancient remains from the Pontic-Caspian steppe.

I'm no longer wondering whether there were massive population movements from Eastern Europe to South Central Asia during the metal ages. It's a given that they happened, and I'm now looking forward to learning about the details from ancient DNA. For instance, what was the ratio of men to women amongst these migrants? And how fair were they exactly?

See also...

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