Yamnaya replaced Europeans, but admixed heavily as they spread to Asia

narasimhan-spread-yamnaya-ancestry

Recent papers The formation of human populations in South and Central Asia, by Narasimhan, Patterson et al. Science (2019) and An Ancient Harappan Genome Lacks Ancestry from Steppe Pastoralists or Iranian Farmers, by Shinde et al. Cell (2019).

NOTE. For direct access to Narasimhan, Patterson et al. (2019), visit this link courtesy of the first author and the Reich Lab.

I am currently not on holidays anymore, and the information in the paper is huge, with many complex issues raised by the new samples and analyses rather than solved, so I will stick to the Indo-European question, especially to some details that have changed since the publication of the preprint. For a summary of its previous findings, see the book series A Song of Sheep and Horses, in particular the sections from A Clash of Chiefs where I discuss languages and regions related to Central and South Asia.

I have updated the maps of the Preshistory Atlas, and included the most recently reported mtDNA and Y-DNA subclades. I will try to update the Eurasian PCA and related graphics, too.

NOTE. Many subclades from this paper have been reported by Kolgeh (download), Pribislav and Principe at Anthrogenica on this thread. I have checked some out for comparison, but even if it contradicted their analyses mine would be the wrong ones. I will upload my spreadsheets and link to them from this page whenever I find the time.

caucasus-cline-narasimhan
Ancestry clines (1) before and (2) after the advent of farming. Colour modified from the original to emphasize the CHG cline: notice the apparent relevance of forest-steppe groups in the formation of this CHG mating network from which Pre-Yamnaya peoples emerged.

Indo-Europeans

I think the Narasimhan, Patterson et al. (2019) paper is well-balanced, and unexpectedly centered – as it should – on the spread of Yamnaya-related ancestry (now Western_Steppe_EMBA) as the marker of Proto-Indo-European migrations, which stretched ca. 3000 BC “from Hungary in the west to the Altai mountains in the east”, spreading later Indo-European dialects after admixing with local groups, from the Atlantic to South Asia.

I. Afanasievo

I.1. East or West PIE?

I expected Afanasievo to show (1) R1b-L23(xZ2103, xL51) and (2) R1b-L51 lineages, apart from (3) the known R1b-Z2103 ones, pointing thus to an ancestral PIE community before the typical Yamnaya bottlenecks, and with R1b-L51 supporting a connection with North-West Indo-European. The presence of some samples of hg. Q pointed in this direction, too.

However, Afanasievo samples show overwhelmingly R1b-Z2103 subclades (all except for those with low coverage), all apparently under R1b-Z2108 (formed ca. 3500 BC, TMRCA ca. 3500 BC), like most samples from East Yamnaya.

This necessarily shifts the split and spread of R1b-L23 lineages to Khvalynsk/early Repin-related expansions, in line with what TMRCA suggested, and what advances by Anthony (2019) and Khokhlov (2018) on future samples from the Reich Lab suggest.

Given the almost indistinguishable ancestry between Afanasievo and Early Yamnaya, there seems to be as of yet little potential information to support in population genomics that Pre-Tocharians were more closely related to North-West Indo-Europeans than to Graeco-Aryans, as it is proposed in linguistics based on the few shared traits between them, and the lack of innovations proper of the Graeco-Aryan community.

NOTE. A new issue of Wekʷos contains an abstract from a relevant paper by Blažek on vocabulary for ‘word’, including the common NWIE *wrdʰo-/wordʰo-, but also a new (for me, at least) Northern Indo-European one: *rēki-/*rēkoi̯-, shared by Slavic and Tocharian.

The fact that bottlenecks happened around the time of the late Repin expansion suggests that we might be able to see different clans based on the predominant lineages developing around the Don-Volga area in the 4th millennium BC. The finding of Pre-R1b-L51 in Lopatino (see below), and of a Catacomb sample of hg. R1b-Z2103(Z2105-) in the North Caucasus steppe near Novoaleksandrovskij also support a star-like phylogeny of R1b-L23 stemming from the Don-Volga area.

NOTE. Interestingly, a dismissal of a common trunk between Tocharian and North-West Indo-European would mean that shared similarities between such disparate groups could be traced back to a Common Late PIE trunk, and not to a shared (western) Repin community. For an example of such a ‘pure’ East-West dialectal division, see the diagram of Adams & Mallory (2007) at the end of the post. It would thus mean a fatal blow to Kortlandt’s Indo-Slavonic group among other hypothetical groupings (remade versions of the ancient Centum-Satem division), as well as to certain assumptions about laryngeal survival or tritectalism that usually accompany them. Still, I don’t think this is the case, so the question will remain a linguistic one, and maybe some similarities will be found with enough number of samples that differentiate Northern Indo-Europeans from the East Yamna/Catacomb-Poltavka-Balkan_EBA group.

afanasievo-y-dna
Y-chromosome haplogroups of Afanasievo samples and neighbouring groups. See full maps.

I.2. Expansion or resurgence of hg. Q1b?

Haplogroup Q1b-Y6802(xY6798) seems to be the main lineage that expanded with Afanasievo, or resurged in their territory. It’s difficult to tell, because the three available samples are family, and belong to a later period.

NOTE. I have finally put some order to the chaos of Q1a vs. Q1b subclades in my spreadsheet and in the maps. The change of ISOGG 2016 to 2017 has caused that many samples reported as of Q1 subclades from papers prepared during the 2017-2018 period, and which did not provide specific SNP calls, were impossible to define with certainty. By checking some of them I could determine the specific standard used.

In favour of the presence of this haplogroup in the Pre-Yamnaya community are:

  • The statement by Anthony (2019) that Q1a [hence maybe Q1b in the new ISOGG nomenclature] represented a significant minority among an R1b-rich community.
  • The sample found in a Sintastha WSHG outlier (see below), of hg. Q1b-Y6798, and the sample from Lola, of hg. Q1b-L717, are thus from other lineage(s) separated thousands of years from the Afanasievo subclade, but might be related to the Khvalynsk expansion, like R1b-V1636 and R1b-M269 are.

These are the data that suggest multiple resurgence events in Afanasievo, rather than expanding Q1b lineages with late Repin:

  • Overwhelming presence of R1b in early Yamnaya and Afanasievo samples; one Q1(xQ1b) sample reported in Khvalynsk.
  • The three Q1b samples appear only later, although wide CI for radiocarbon dates, different sites, and indistinguishable ancestry may preclude a proper interpretation of the only available family.
    • Nevertheless, ancestry seems unimportant in the case of Afanasievo, since the same ancestry is found up to the Iron Age in a community of varied haplogroups.
  • Another sample of hg. Q1b-Y6802(xY6798) is found in Aigyrzhal_BA (ca. 2120 BC), with Central_Steppe_EMBA (WSHG-related) ancestry; however, this clade formed and expanded ca. 14000 BC.
  • The whole Altai – Baikal area seems to be a Q1b-L54 hotspot, although admittedly many subclades separated very early from each other, so they might be found throughout North Eurasia during the Neolithic.
  • One Afanasievo sample is reported as of hg. C in Shin (2017), and the same haplogroup is reported by Hollard (2014) for the only available sample of early Chemurchek to date, from Kulala ula, North Altai (ca. 2400 BC).
afanasievo-chemurchek-y-dna
Y-chromosome haplogroups of late Afanasievo – early Chemurchek samples and neighbouring groups. See full maps.

I.3. Agricultural substrate

Evidence of continuous contacts of Central_Steppe_MLBA populations with BMAC from ca. 2100 BC on – visible in the appearance of Steppe ancestry among BMAC samples and BMAC ancestry among Steppe pastoralists – supports the close interaction between Indo-Iranian pastoralists and BMAC agriculturalists as the origin of the Asian agricultural substrate found in Proto-Indo-Iranian, hence likely related to the language of the Oxus Civilization.

Similar to the European agricultural substrate adopted by West Yamnaya settlers (both NWIE and Palaeo-Balkan speakers), Tocharian shows a few substrate terms in common with Indo-Iranian, which can be explained by contacts in different dialectal stages through phonetic reconstruction alone.

The recent Hermes et al. (2019) supports the early integration of pastoralism and millet cultivation in Central Asia (ca. 2700 BC or earlier), with the spread of agriculture to the north – through the Inner Asian Mountain Corridor – being thus unrelated to the Indo-Iranian expansions, which might support independent loans.

However, compared to the huge number of parallel shared loans between NWIE and Palaeo-Balkan languages in the European substratum, Indo-Iranians seem to have been the first borrowers of vocabulary from Asian agriculturalists, while Proto-Tocharian shows just one certain related word, with phonetic similarities that warrant an adoption from late Indo-Iranian dialects.

chemurchek-sintashta-bmac
Y-chromosome haplogroups of Sintashta, Central Asia, and neighbouring groups in the Early Bronze Age. See full maps.

The finding of hg. (pre-)R1b-PH155 in a BMAC sample from Dzharkutan (to the west of Xinjiang) together with hg. R1b in a sample from Central Mongolia previously reported by Shin (2017) support the widespread presence of this lineage to the east and west of Xinjiang, which means it might have become incorporated to Indo-Iranian migrants into the Xiaohe horizon, to the Afanasievo-Chemurchek-derived groups, or the later from the former. In other words, the Island Biogeography Theory with its explanation of founder effects might be, after all, applicable to the whole Xinjiang area, not only during the Chemurchek – Tianshan-Beilu – Xiaohe interaction.

Of course, there is no need for too complicated models of haplogroup resurgence events in Central and South Asia, seeing how the total amount of hg. R1a-L657 (today prevalent among Indo-Aryan speakers from South Asia) among ancient Western/Central_Steppe_MLBA-related samples amounts to a total of 0, and that many different lineages survived in the region. Similar cases of haplogroup resurgence and Y-DNA bottleneck events are also found in the Central and Eastern Mediterranean, and in North-Eastern Europe. From the paper:

[It] could reflect stronger ecological or cultural barriers to the spread of people in South Asia than in Europe, allowing the previously established groups more time to adapt and mix with incoming groups. A second difference is the smaller proportion of Steppe pastoralist– related ancestry in South Asia compared with Europe, its later arrival by ~500 to 1000 years, and a lower (albeit still significant) male sex bias in the admixture (…).

Y-chromosome haplogroups of samples from the Srubna-Andronovo and Andronovo-related horizon, Xiaohe, late BMAC, and neighbouring groups. See full maps.

II. R1b-Beakers replaced R1a-CWC peoples

II.1. R1a-M417-rich Corded Ware

Newly reported Corded Ware samples from Radovesice show hg. R1a-M417, at least some of them xZ645, ‘archaic’ lineages shared with the early Bergrheinfeld sample (ca. 2650 BC) and with the coeval Esperstedt family, hence supporting that it eventually became the typical Western Corded Ware lineage(s), probably dominating over the so-called A-horizon and the Single Grave culture in particular. On the other hand, R1a-Z645 was typical of bottlenecks among expanding Eastern Corded Ware groups.

Interestingly, it is supported once again that known bottlenecks under hg. R1a-M417 happened during the Corded Ware expansion, evidenced also by the remarkable high variability of male lineages among early Corded Ware samples. Similarly, these Corded Ware samples from Bohemia form part of the typical ‘Central European’ cluster in the PCA, which excludes once again not only the ‘official’ Espersted outlier I1540, but also the known outlier with Yamnaya ancestry.

NOTE. The fact that Esperstedt is closely related geographically and in terms of ancestry to later Únětice samples further complicates the assumption that Únětice is a mixture of Bell Beakers and Corded Ware, being rather an admixture of incoming Bell Beakers with post-Yamnaya vanguard settlers who admixed with Corded Ware (see more on the expansion of Yamnaya ancestry). In other words, Únětice is rather an admixture of Yamnaya+EEF with Yamnaya+(CWC+EEF).

Y-chromosome haplogroups of samples from Catacomb, Poltavka, Balkan EBA, and Bell Beaker, as well as neighbouring groups. See full maps.

On Ukraine_Eneolithic I6561

If the bottlenecks are as straightforward as they appear, with a star-like phylogeny of R1a-M417 starting with the Pre-Corded Ware expansion, then what is happening with the Alexandria sample, so precisely radiocarbon dated to ca. 4045-3974 BC? The reported hg. R1a-M417 was fully compatible, while R1a-Z645 could be compatible with its date, but the few positive SNPs I got in my analysis point indeed to a potential subclade of R1a-Z94, and I trust more experienced hobbyists in this ‘art’ of ascertaining the SNPs of ancient samples, and they report hg. R1a-Z93 (Z95+, Y26+, Y2-).

Seeing how Y-DNA bottlenecks worked in Yamnaya-Afanasievo and in Corded Ware and related groups, and if this sample really is so deep within R1a-Z93 in a region that should be more strongly affected by the known Neolithic Y-chromosome bottlenecks and forest-steppe ecotone, someone from the lab responsible for this sample should check its date once again, before more people keep chasing their tails with an individual that (based on its derived SNPs’ TMRCA) might actually be dated to the Bronze Age, where it could make much more sense in terms of ancestry and position in the PCA.

EDIT (14 SEP 2019): … and with the fact that he is the first individual to show the genetic adaptation for lactase persistence (I3910-T), which is only found later among Bell Beakers, and much later in Sintashta and related Steppe_MLBA peoples (see comments below).

This is also evidenced by the other Ukraine_Eneolithic (likely a late Yamnaya) sample of hg. R1b-Z2103 from Dereivka (ca. 2800 BC) and who – despite being in a similar territory 1,000 years later – shows a wholly diluted Yamnaya ancestry under typically European HG ancestry, even more so than other late Sredni Stog samples from Dereivka of ca. 3600-3400 BC, suggesting a decrease in Steppe ancestry rather than an increase – which is supposedly what should be expected based on the ancestry from Alexandria…

Like the reported Chalcolithic individual of Hajji Firuz who showed an apparently incompatible subclade and Yamnaya ancestry at least some 1,000 years before it should, and turned out to be from the Iron Age (see below), this may be another case of wrong radiocarbon dating.

NOTE. It would be interesting, if this turns out to be another Hajji Firuz-like error, to check how well different ancestry models worked in whose hands exactly, and if anyone actually pointed out that this sample was derived, and not ancestral, to many different samples that were used in combination with it. It would also be a great control to check if those still supporting a Sredni Stog origin for PIE would shift their preference even more to the north or west, depending on where the first “true” R1a-M417 samples popped up. Such a finding now could be thus a great tool to discover whether haplogroup-based bias plays a role in ancestry magic as related to the Indo-European question, i.e. if it really is about “pure statistics”, or there is something else to it…

II.1. R1b-L51-rich Bell Beakers

The overwhelming majority of R1b-L51 lineages in Radovesice during the Bell Beaker period, just after the sampled Corded Ware individuals from the same site, further strengthen the hypothesis of an almost full replacement of R1a-M417 lineages from Central Europe up to southern Scandinavia after the arrival of Bell Beakers.

Yet another R1b-L151* sample has popped up in Central Europe, in the individual classified as Bilina_BA (ca. 2200-800 BC), which clusters with Bell Beakers from Bohemia, with the outlier from Turlojiškė, and with Early Slavs, suggesting once again that a group of central-east European Beakers represented the Pre-Proto-Balto-Slavic community before their spread and admixture events to the east.

The available ancient distribution of R1b-L51*, R1b-L52* or R1b-L151* is getting thus closer to the most likely origin of R1b-L51 in the expansion of East Bell Beakers, who trace their paternal ancestors to Yamnaya settlers from the Carpathian Basin:

NOTE. Some of these are from other sources, and some are samples I have checked in a hurry, so I may have missed some derived SNPs. If you send me a corrected SNP call to dismiss one of these, or more ‘archaic’ samples, I’ll correct the map accordingly. See also maps of modern distributionof R1b-M269 subclades .

r1b-l51-ancient-europe
Distribution of ‘archaic’ R1b-L51 subclades in ancient samples, overlaid over a map of Yamnaya and Bell Beaker migrations. In blue, Yamnaya Pre-L51 from Lopatino (not shown) and R1b-L52* from BBC Augsburg. In violet, R1b-L51 (xP312,xU106) from BBC Prague and Poland. In maroon, hg. R1b-L151* from BBC Hungary, BA Bohemia, and (not shown) a potential sample from BBC at Mondelange, which is certainly xU106, maybe xP312. Interestingly, the earliest sample of hg. R1b-U106 (a lineage more proper of northern Europe) has been found in a Bell Beaker from Radovesice (ca. 2350 BC), between two of these ‘archaic’ R1b-L51 samples; and a sample possibly of hg. R1b-ZZ11+ (ancestral to DF27 and U152) was found in a Bell Beaker from Quedlinburg, Germany (ca. 2290 BC), to the north-west of Bohemia. The oldest R1b-U152 are logically from Central Europe, too.

III. Proto-Indo-Iranian

Before the emergence of Proto-Indo-Iranian, it seems that Pre-Proto-Indo-Iranian-speaking Poltavka groups were subjected to pressure from Central_Steppe_EMBA-related peoples coming from the (south-?)east, such as those found sampled from Mereke_BA. Their ‘kurgan’ culture was dated correctly to approximately the same date as Poltavka materials, but their ancestry and hg. N2(pre-N2a) – also found in a previous sample from Botai – point to their intrusive nature, and thus to difficulties in the Pre-Proto-Indo-Iranian community to keep control over the previous East Yamnaya territory in the Don-Volga-Ural steppes.

We know that the region does not show genetic continuity with a previous period (or was not under this ‘eastern’ pressure) because of an Eastern Yamnaya sample from the same site (ca. 3100 BC) showing typical Yamnaya ancestry. Before Yamnaya, it is likely that Pre-Yamnaya ancestry formed through admixture of EHG-like Khvalynsk with a North Caspian steppe population similar to the Steppe_Eneolithic samples from the North Caucasus Piedmont (see Anthony 2019), so we can also rule out some intermittent presence of a Botai/Kelteminar-like population in the region during the Khvalynsk period.

It is very likely, then, that this competition for the same territory – coupled with the known harsher climate of the late 3rd millennium BC – led Poltavka herders to their known joint venture with Abashevo chiefs in the formation of the Sintashta-Potapovka-Filatovka community of fortified settlements. Supporting these intense contacts of Poltavka herders with Central Asian populations, late ‘outliers’ from the Volga-Ural region show admixture with typical Central_Steppe_MLBA populations: one in Potapovka (ca. 2220 BC), of hg. R1b-Z2103; and four in the Sintashta_MLBA_o1 cluster (ca. 2050-1650 BC), with two samples of hg. R1b-L23 (one R1b-Z2109), one Q1b-L56(xL53), one Q1b-Y6798.

central-steppe-pastoralists
Outlier analysis reveals ancient contacts between sites. We plot the average of principal component 1 (x axis) and principal component 2 (y axis) for the West Eurasian and All Eurasian PCA plots (…). In the Middle to Late Bronze Age Steppe, we observe, in addition to the Western_Steppe_MLBA and Central_Steppe_MLBA clusters (indistinguishable in this projection), outliers admixed with other ancestries. The BMAC-related admixture in Kazakhstan documents northward gene flow onto the Steppe and confirms the Inner Asian Mountain Corridor as a conduit for movement of people.

Similar to how the Sintashta_MLBA_o2 cluster shows an admixture with central steppe populations and hg. R1a-Z645, the WSHG ancestry in those outliers from the o1 cluster of typically (or potentially) Yamnaya lineages show that Poltavka-like herders survived well after centuries of Abashevo-Poltavka coexistence and admixture events, supporting the formation of a Proto-Indo-Iranian community from the local language as pronounced by the incomers, who dominated as elites over the fortified settlements.

The Proto-Indo-Iranian community likely formed thus in situ in the Don-Volga-Ural region, from the admixture of locals of Yamnaya ancestry with incomers of Corded Ware ancestry – represented by the ca. 67% Yamnaya-like ancestry and ca. 33% ancestry from the European cline. Their community formed thus ca. 1,000 years later than the expansion of Late PIE ca. 3500 BC, and expanded (some 500 years after that) a full-fledged Proto-Indo-Iranian language with the Srubna-Andronovo horizon, further admixing with ca. 9% of Central_Steppe_EMBA (WSHG-related) ancestry in their migration through Central Asia, as reported in the paper.

IV. Armenian

The sample from Hajji Firuz, of hg. R1b-Z2103 (xPF331), has been – as expected – re-dated to the Iron Age (ca. 1193-1019 BC), hence it may offer – together with the samples from the Levant and their Aegean-like ancestry rapidly diluted among local populations – yet another proof of how the Late Bronze Age upheaval in Europe was the cause of the Armenian migration to the Armenoid homeland, where they thrived under the strong influence from Hurro-Urartian.

middle-east-armenia-y-dna
Y-chromosome haplogroups of the Middle East and neighbouring groups during the Late Bronze Age / Iron Age. See full maps.

Indus Valley Civilization and Dravidian

A surprise came from the analysis reported by Shinde et al. (2019) of an Iran_N-related IVC ancestry which may have split earlier than 10000 BC from a source common to Iran hunter-gatherers of the Belt Cave.

For the controversial Elamo-Dravidian hypothesis of the Muscovite school, this difference in ancestry between both groups (IVC and Iran Neolithic) seems to be a death blow, if population genomics was even needed for that. Nevertheless, I guess that a full rejection of a recent connection will come down to more recent and subtle population movements in the area.

EDIT (12 SEP): Apparently, Iosif Lazaridis is not so sure about this deep splitting of ‘lineages’ as shown in the paper, so we may be talking about different contributions of AME+ANE/ENA, which means the Elamo-Dravidian game is afoot; at least in genomics:

I shared the idea that the Indus Valley Civilization was linked to the Proto-Dravidian community, so I’m inclined to support this statement by Narasimhan, Patterson, et al. (2019), even if based only on modern samples and a few ancient ones:

The strong correlation between ASI ancestry and present-day Dravidian languages suggests that the ASI, which we have shown formed as groups with ancestry typical of the Indus Periphery Cline moved south and east after the decline of the IVC to mix with groups with more AASI ancestry, most likely spoke an early Dravidian language.

india-steppe-indus-valley-andamanese-ancestry
Natural neighbour interpolation of qpAdm results – Maximum A Posteriori Estimate from the Hierarchical Model (estimates used in the Narasimhan, Patterson et al. 2019 figures) for Central_Steppe_MLBA-related (left), Indus_Periphery_West-related (center) and Andamanese_Hunter-Gatherer-related ancestry (right) among sampled modern Indian populations. In blue, peoples of IE language; in red, Dravidian; in pink, Tibeto-Burman; in black, unclassified. See full image.

I am wary of this sort of simplistic correlation with modern speakers, because we have seen what happened with the wrong assumptions about modern Balto-Slavic and Finno-Ugric speakers and their genetic profile (see e.g. here or here). In fact, I just can’t differentiate as well as those with deep knowledge in South Asian history the social stratification of the different tribal groups – with their endogamous rules under the varna and jati systems – in the ancestry maps of modern India. The pattern of ancestry and language distribution combined with the findings of ancient populations seem in principle straightforward, though.

Conclusion

The message to take home from Shinde et al. (2019) is that genomic data is fully at odds with the Anatolian homeland hypothesis – including the latest model by Heggarty (2014)* – whose relevance is still overvalued today, probably due in part to the shift of OIT proponents to more reasonable Out-of-Iran models, apparently more fashionable as a vector of Indo-Aryan languages than Eurasian steppe pastoralists?
*The authors listed this model erroneously as Heggarty (2019).

The paper seems to play with the occasional reference to Corded Ware as a vector of expansion of Indo-European languages, even after accepting the role of Yamnaya as the most evident population expanding Late PIE to western Europe – and the different ancestry that spread with Indo-Iranian to South Asia 1,000 years later. However, the most cringe-worthy aspect is the sole citation of the debunked, pseudoscientific glottochronological method used by Ringe, Warnow, and Taylor (2002) to support the so-called “steppe homeland”, a paper and dialectal scheme which keeps being referenced in papers of the Reich Lab, probably as a consequence of its use in Anthony (2007).

On the other hand, these are the equivalent simplistic comments in Narasimhan, Patterson et al. (2019):

The Steppe ancestry in South Asia has the same profile as that in Bronze Age Eastern Europe, tracking a movement of people that affected both regions and that likely spread the unique features shared between Indo-Iranian and Balto-Slavic languages. (…), which despite their vast geographic separation share the “satem” innovation and “ruki” sound laws.

mallory-adams-tree
Indo-European dialectal relationships, from Mallory and Adams (2006).

The only academic closely related to linguistics from the list of authors, as far as I know, is James P. Mallory, who has supported a North-West Indo-European dialect (including Balto-Slavic) for a long time – recently associating its expansion with Bell Beakers – opposed thus to a Graeco-Aryan group which shared certain innovations, “Satemization” not being one of them. Not that anyone needs to be a linguist to dismiss any similarities between Balto-Slavic and Indo-Iranian beyond this phonetic trend, mind you.

Even Anthony (2019) supports now R1b-rich Pre-Yamnaya and Yamnaya communities from the Don-Volga region expanding Middle and Late Proto-Indo-European dialects.

So how does the underlying Corded Ware ancestry of eastern Europe (where Pre-Balto-Slavs eventually spread to from Bell Beaker-derived groups) and of the highly admixed (“cosmopolitan”, according to the authors) Sintashta-Potapovka-Filatovka in the east relate to the similar-but-different phonetic trends of two unrelated IE dialects?

If only there was a language substrate that could (as Shinde et al. put it) “elegantly” explain this similar phonetic evolution, solving at the same time the question of the expansion of Uralic languages and their strong linguistic contacts with steppe peoples. Say, Eneolithic populations of mainly hunter-fisher-gatherers from the North Pontic forest-steppes with a stronger connection to metalworking

Related

Yamnaya ancestry: mapping the Proto-Indo-European expansions

steppe-ancestry-expansion-europe

The latest papers from Ning et al. Cell (2019) and Anthony JIES (2019) have offered some interesting new data, supporting once more what could be inferred since 2015, and what was evident in population genomics since 2017: that Proto-Indo-Europeans expanded under R1b bottlenecks, and that the so-called “Steppe ancestry” referred to two different components, one – Yamnaya or Steppe_EMBA ancestry – expanding with Proto-Indo-Europeans, and the other one – Corded Ware or Steppe_MLBA ancestry – expanding with Uralic speakers.

The following maps are based on formal stats published in the papers and supplementary materials from 2015 until today, mainly on Wang et al. (2018 & 2019), Mathieson et al. (2018) and Olalde et al. (2018), and others like Lazaridis et al. (2016), Lazaridis et al. (2017), Mittnik et al. (2018), Lamnidis et al. (2018), Fernandes et al. (2018), Jeong et al. (2019), Olalde et al. (2019), etc.

NOTE. As in the Corded Ware ancestry maps, the selected reports in this case are centered on the prototypical Yamnaya ancestry vs. other simplified components, so everything else refers to simplistic ancestral components widespread across populations that do not necessarily share any recent connection, much less a language. In fact, most of the time they clearly didn’t. They can be interpreted as “EHG that is not part of the Yamnaya component”, or “CHG that is not part of the Yamnaya component”. They can’t be read as “expanding EHG people/language” or “expanding CHG people/language”, at least no more than maps of “Steppe ancestry” can be read as “expanding Steppe people/language”. Also, remember that I have left the default behaviour for color classification, so that the highest value (i.e. 1, or white colour) could mean anything from 10% to 100% depending on the specific ancestry and period; that’s what the legend is for… But, fere libenter homines id quod volunt credunt.

Sections:

  1. Neolithic or the formation of Early Indo-European
  2. Eneolithic or the expansion of Middle Proto-Indo-European
  3. Chalcolithic / Early Bronze Age or the expansion of Late Proto-Indo-European
  4. European Early Bronze Age and MLBA or the expansion of Late PIE dialects

1. Neolithic

Anthony (2019) agrees with the most likely explanation of the CHG component found in Yamnaya, as derived from steppe hunter-fishers close to the lower Volga basin. The ultimate origin of this specific CHG-like component that eventually formed part of the Pre-Yamnaya ancestry is not clear, though:

The hunter-fisher camps that first appeared on the lower Volga around 6200 BC could represent the migration northward of un-admixed CHG hunter-fishers from the steppe parts of the southeastern Caucasus, a speculation that awaits confirmation from aDNA.

neolithic-chg-ancestry
Natural neighbor interpolation of CHG ancestry among Neolithic populations. See full map.

The typical EHG component that formed part eventually of Pre-Yamnaya ancestry came from the Middle Volga Basin, most likely close to the Samara region, as shown by the sampled Samara hunter-gatherer (ca. 5600-5500 BC):

After 5000 BC domesticated animals appeared in these same sites in the lower Volga, and in new ones, and in grave sacrifices at Khvalynsk and Ekaterinovka. CHG genes and domesticated animals flowed north up the Volga, and EHG genes flowed south into the North Caucasus steppes, and the two components became admixed.

neolithic-ehg-ancestry
Natural neighbor interpolation of EHG ancestry among Neolithic populations. See full map.

To the west, in the Dnieper-Dniester area, WHG became the dominant ancestry after the Mesolithic, at the expense of EHG, revealing a likely mating network reaching to the north into the Baltic:

Like the Mesolithic and Neolithic populations here, the Eneolithic populations of Dnieper-Donets II type seem to have limited their mating network to the rich, strategic region they occupied, centered on the Rapids. The absence of CHG shows that they did not mate frequently if at all with the people of the Volga steppes (…)

neolithic-whg-ancestry
Natural neighbor interpolation of WHG ancestry among Neolithic populations. See full map.

North-West Anatolia Neolithic ancestry, proper of expanding Early European farmers, is found up to border of the Dniester, as Anthony (2007) had predicted.

neolithic-anatolia-farmer-ancestry
Natural neighbor interpolation of Anatolia Neolithic ancestry among Neolithic populations. See full map.

2. Eneolithic

From Anthony (2019):

After approximately 4500 BC the Khvalynsk archaeological culture united the lower and middle Volga archaeological sites into one variable archaeological culture that kept domesticated sheep, goats, and cattle (and possibly horses). In my estimation, Khvalynsk might represent the oldest phase of PIE.

(…) this middle Volga mating network extended down to the North Caucasian steppes, where at cemeteries such as Progress-2 and Vonyuchka, dated 4300 BC, the same Khvalynsk-type ancestry appeared, an admixture of CHG and EHG with no Anatolian Farmer ancestry, with steppe-derived Y-chromosome haplogroup R1b. These three individuals in the North Caucasus steppes had higher proportions of CHG, overlapping Yamnaya. Without any doubt, a CHG population that was not admixed with Anatolian Farmers mated with EHG populations in the Volga steppes and in the North Caucasus steppes before 4500 BC. We can refer to this admixture as pre-Yamnaya, because it makes the best currently known genetic ancestor for EHG/CHG R1b Yamnaya genomes.

From Wang et al (2019):

Three individuals from the sites of Progress 2 and Vonyuchka 1 in the North Caucasus piedmont steppe (‘Eneolithic steppe’), which harbour EHG and CHG related ancestry, are genetically very similar to Eneolithic individuals from Khvalynsk II and the Samara region. This extends the cline of dilution of EHG ancestry via CHG-related ancestry to sites immediately north of the Caucasus foothills

eneolithic-pre-yamnaya-ancestry
Natural neighbor interpolation of Pre-Yamnaya ancestry among Neolithic populations. See full map. This map corresponds roughly to the map of Khvalynsk-Novodanilovka expansion, and in particular to the expansion of horse-head pommel-scepters (read more about Khvalynsk, and specifically about horse symbolism)

NOTE. Unpublished samples from Ekaterinovka have been previously reported as within the R1b-L23 tree. Interestingly, although the Varna outlier is a female, the Balkan outlier from Smyadovo shows two positive SNP calls for hg. R1b-M269. However, its poor coverage makes its most conservative haplogroup prediction R-M343.

The formation of this Pre-Yamnaya ancestry sets this Volga-Caucasus Khvalynsk community apart from the rest of the EHG-like population of eastern Europe.

eneolithic-ehg-ancestry
Natural neighbor interpolation of non-Pre-Yamnaya EHG ancestry among Eneolithic populations. See full map.

Anthony (2019) seems to rely on ADMIXTURE graphics when he writes that the late Sredni Stog sample from Alexandria shows “80% Khvalynsk-type steppe ancestry (CHG&EHG)”. While this seems the most logical conclusion of what might have happened after the Suvorovo-Novodanilovka expansion through the North Pontic steppes (see my post on “Steppe ancestry” step by step), formal stats have not confirmed that.

In fact, analyses published in Wang et al. (2019) rejected that Corded Ware groups are derived from this Pre-Yamnaya ancestry, a reality that had been already hinted in Narasimhan et al. (2018), when Steppe_EMBA showed a poor fit for expanding Srubna-Andronovo populations. Hence the need to consider the whole CHG component of the North Pontic area separately:

eneolithic-chg-ancestry
Natural neighbor interpolation of non-Pre-Yamnaya CHG ancestry among Eneolithic populations. See full map. You can read more about population movements in the late Sredni Stog and closer to the Proto-Corded Ware period.

NOTE. Fits for WHG + CHG + EHG in Neolithic and Eneolithic populations are taken in part from Mathieson et al. (2019) supplementary materials (download Excel here). Unfortunately, while data on the Ukraine_Eneolithic outlier from Alexandria abounds, I don’t have specific data on the so-called ‘outlier’ from Dereivka compared to the other two analyzed together, so these maps of CHG and EHG expansion are possibly showing a lesser distribution to the west than the real one ca. 4000-3500 BC.

eneolithic-whg-ancestry
Natural neighbor interpolation of WHG ancestry among Eneolithic populations. See full map.

Anatolia Neolithic ancestry clearly spread to the east into the north Pontic area through a Middle Eneolithic mating network, most likely opened after the Khvalynsk expansion:

eneolithic-anatolia-farmer-ancestry
Natural neighbor interpolation of Anatolia Neolithic ancestry among Eneolithic populations. See full map.
eneolithic-iran-chl-ancestry
Natural neighbor interpolation of Iran Chl. ancestry among Eneolithic populations. See full map.

Regarding Y-chromosome haplogroups, Anthony (2019) insists on the evident association of Khvalynsk, Yamnaya, and the spread of Pre-Yamnaya and Yamnaya ancestry with the expansion of elite R1b-L754 (and some I2a2) individuals:

eneolithic-early-y-dna
Y-DNA haplogroups in West Eurasia during the Early Eneolithic in the Pontic-Caspian steppes. See full map, and see culture, ADMIXTURE, Y-DNA, and mtDNA maps of the Early Eneolithic and Late Eneolithic.

3. Early Bronze Age

Data from Wang et al. (2019) show that Corded Ware-derived populations do not have good fits for Eneolithic_Steppe-like ancestry, no matter the model. In other words: Corded Ware populations show not only a higher contribution of Anatolia Neolithic ancestry (ca. 20-30% compared to the ca. 2-10% of Yamnaya); they show a different EHG + CHG combination compared to the Pre-Yamnaya one.

eneolithic-steppe-best-fits
Supplementary Table 13. P values of rank=2 and admixture proportions in modelling Steppe ancestry populations as a three-way admixture of Eneolithic steppe Anatolian_Neolithic and WHG using 14 outgroups.
Left populations: Test, Eneolithic_steppe, Anatolian_Neolithic, WHG.
Right populations: Mbuti.DG, Ust_Ishim.DG, Kostenki14, MA1, Han.DG, Papuan.DG, Onge.DG, Villabruna, Vestonice16, ElMiron, Ethiopia_4500BP.SG, Karitiana.DG, Natufian, Iran_Ganj_Dareh_Neolithic.

Yamnaya Kalmykia and Afanasievo show the closest fits to the Eneolithic population of the North Caucasian steppes, rejecting thus sizeable contributions from Anatolia Neolithic and/or WHG, as shown by the SD values. Both probably show then a Pre-Yamnaya ancestry closest to the late Repin population.

wang-eneolithic-steppe-caucasus-yamnaya
Modelling results for the Steppe and Caucasus cluster. Admixture proportions based on (temporally and geographically) distal and proximal models, showing additional AF ancestry in Steppe groups and additional gene flow from the south in some of the Steppe groups as well as the Caucasus groups. See tables above. Modified from Wang et al. (2019). Within a blue square, Yamnaya-related groups; within a cyan square, Corded Ware-related groups. Green background behind best p-values. In red circle, SD of AF/WHG ancestry contribution in Afanasevo and Yamnaya Kalmykia, with ranges that almost include 0%.

EBA maps include data from Wang et al. (2018) supplementary materials, specifically unpublished Yamnaya samples from Hungary that appeared in analysis of the preprint, but which were taken out of the definitive paper. Their location among Yamnaya settlers from Hungary is speculative, although most uncovered kurgans in Hungary are concentrated in the Tisza-Danube interfluve.

eba-yamnaya-ancestry
Natural neighbor interpolation of Pre-Yamnaya ancestry among Early Bronze Age populations. See full map. This map corresponds roughly with the known expansion of late Repin/Yamnaya settlers.

The Y-chromosome bottleneck of elite males from Proto-Indo-European clans under R1b-L754 and some I2a2 subclades, already visible in the Khvalynsk sampling, became even more noticeable in the subsequent expansion of late Repin/early Yamnaya elites under R1b-L23 and I2a-L699:

chalcolithic-early-y-dna
Y-DNA haplogroups in West Eurasia during the Yamnaya expansion. See full map and maps of cultures, ADMIXTURE, Y-DNA, and mtDNA of the Early Chalcolithic and Yamnaya Hungary.

Maps of CHG, EHG, Anatolia Neolithic, and probably WHG show the expansion of these components among Corded Ware-related groups in North Eurasia, apart from other cultures close to the Caucasus:

NOTE. For maps with actual formal stats of Corded Ware ancestry from the Early Bronze Age to the modern times, you can read the post Corded Ware ancestry in North Eurasia and the Uralic expansion.

eba-chg-ancestry
Natural neighbor interpolation of non-Pre-Yamnaya CHG ancestry among Early Bronze Age populations. See full map.
eba-ehg-ancestry
Natural neighbor interpolation of non-Pre-Yamnaya EHG ancestry among Early Bronze Age populations. See full map.
eba-whg-ancestry
Natural neighbor interpolation of WHG ancestry among Early Bronze Age populations. See full map.
eba-anatolia-farmer-ancestry
Natural neighbor interpolation of Anatolia Neolithic ancestry among Early Bronze Age populations. See full map.
eba-iran-chl-ancestry
Natural neighbor interpolation of Iran Chl. ancestry among Early Bronze Age populations. See full map.

4. Middle to Late Bronze Age

The following maps show the most likely distribution of Yamnaya ancestry during the Bell Beaker-, Balkan-, and Sintashta-Potapovka-related expansions.

4.1. Bell Beakers

The amount of Yamnaya ancestry is probably overestimated among populations where Bell Beakers replaced Corded Ware. A map of Yamnaya ancestry among Bell Beakers gets trickier for the following reasons:

  • Expanding Repin peoples of Pre-Yamnaya ancestry must have had admixture through exogamy with late Sredni Stog/Proto-Corded Ware peoples during their expansion into the North Pontic area, and Sredni Stog in turn had probably some Pre-Yamnaya admixture, too (although they don’t appear in the simplistic formal stats above). This is supported by the increase of Anatolia farmer ancestry in more western Yamna samples.
  • Later, Yamnaya admixed through exogamy with Corded Ware-like populations in Central Europe during their expansion. Even samples from the Middle to Upper Danube and around the Lower Rhine will probably show increasing contributions of Steppe_MLBA, at the same time as they show an increasing proportion of EEF-related ancestry.
  • To complicate things further, the late Corded Ware Espersted family (from ca. 2500 BC or later) shows, in turn, what seems like a recent admixture with Yamnaya vanguard groups, with the sample of highest Yamnaya ancestry being the paternal uncle of other individuals (all of hg. R1a-M417), suggesting that there might have been many similar Central European mating networks from the mid-3rd millennium BC on, of (mainly) Yamnaya-like R1b elites displaying a small proportion of CW-like ancestry admixing through exogamy with Corded Ware-like peoples who already had some Yamnaya ancestry.
mlba-yamnaya-ancestry
Natural neighbor interpolation of Yamnaya ancestry among Middle to Late Bronze Age populations (Esperstedt CWC site close to BK_DE, label is hidden by BK_DE_SAN). See full map. You can see how this map correlated with the map of Late Copper Age migrations and Yamanaya into Bell Beaker expansion.

NOTE. Terms like “exogamy”, “male-driven migration”, and “sex bias”, are not only based on the Y-chromosome bottlenecks visible in the different cultural expansions since the Palaeolithic. Despite the scarce sampling available in 2017 for analysis of “Steppe ancestry”-related populations, it appeared to show already a male sex bias in Goldberg et al. (2017), and it has been confirmed for Neolithic and Copper Age population movements in Mathieson et al. (2018) – see Supplementary Table 5. The analysis of male-biased expansion of “Steppe ancestry” in CWC Esperstedt and Bell Beaker Germany is, for the reasons stated above, not very useful to distinguish their mutual influence, though.

Based on data from Olalde et al. (2019), Bell Beakers from Germany are the closest sampled ones to expanding East Bell Beakers, and those close to the Rhine – i.e. French, Dutch, and British Beakers in particular – show a clear excess “Steppe ancestry” due to their exogamy with local Corded Ware groups:

Only one 2-way model fits the ancestry in Iberia_CA_Stp with P-value>0.05: Germany_Beaker + Iberia_CA. Finding a Bell Beaker-related group as a plausible source for the introduction of steppe ancestry into Iberia is consistent with the fact that some of the individuals in the Iberia_CA_Stp group were excavated in Bell Beaker associated contexts. Models with Iberia_CA and other Bell Beaker groups such as France_Beaker (P-value=7.31E-06), Netherlands_Beaker (P-value=1.03E-03) and England_Beaker (P-value=4.86E-02) failed, probably because they have slightly higher proportions of steppe ancestry than the true source population.

olalde-iberia-chalcolithic

The exogamy with Corded Ware-like groups in the Lower Rhine Basin seems at this point undeniable, as is the origin of Bell Beakers around the Middle-Upper Danube Basin from Yamnaya Hungary.

To avoid this excess “Steppe ancestry” showing up in the maps, since Bell Beakers from Germany pack the most Yamnaya ancestry among East Bell Beakers outside Hungary (ca. 51.1% “Steppe ancestry”), I equated this maximum with BK_Scotland_Ach (which shows ca. 61.1% “Steppe ancestry”, highest among western Beakers), and applied a simple rule of three for “Steppe ancestry” in Dutch and British Beakers.

NOTE. Formal stats for “Steppe ancestry” in Bell Beaker groups are available in Olalde et al. (2018) supplementary materials (PDF). I didn’t apply this adjustment to Bk_FR groups because of the R1b Bell Beaker sample from the Champagne/Alsace region reported by Samantha Brunel that will pack more Yamnaya ancestry than any other sampled Beaker to date, hence probably driving the Yamnaya ancestry up in French samples.

The most likely outcome in the following years, when Yamnaya and Corded Ware ancestry are investigated separately, is that Yamnaya ancestry will be much lower the farther away from the Middle and Lower Danube region, similar to the case in Iberia, so the map above probably overestimates this component in most Beakers to the north of the Danube. Even the late Hungarian Beaker samples, who pack the highest Yamnaya ancestry (up to 75%) among Beakers, represent likely a back-migration of Moravian Beakers, and will probably show a contribution of Corded Ware ancestry due to the exogamy with local Moravian groups.

Despite this decreasing admixture as Bell Beakers spread westward, the explosive expansion of Yamnaya R1b male lineages (in words of David Reich) and the radical replacement of local ones – whether derived from Corded Ware or Neolithic groups – shows the true extent of the North-West Indo-European expansion in Europe:

chalcolithic-late-y-dna
Y-DNA haplogroups in West Eurasia during the Bell Beaker expansion. See full map and see maps of cultures, ADMIXTURE, Y-DNA, and mtDNA of the Late Copper Age and of the Yamnaya-Bell Beaker transition.

4.2. Palaeo-Balkan

There is scarce data on Palaeo-Balkan movements yet, although it is known that:

  1. Yamnaya ancestry appears among Mycenaeans, with the Yamnaya Bulgaria sample being its best current ancestral fit;
  2. the emergence of steppe ancestry and R1b-M269 in the eastern Mediterranean was associated with Ancient Greeks;
  3. Thracians, Albanians, and Armenians also show R1b-M269 subclades and “Steppe ancestry”.

4.3. Sintashta-Potapovka-Filatovka

Interestingly, Potapovka is the only Corded Ware derived culture that shows good fits for Yamnaya ancestry, despite having replaced Poltavka in the region under the same Corded Ware-like (Abashevo) influence as Sintashta.

This proves that there was a period of admixture in the Pre-Proto-Indo-Iranian community between CWC-like Abashevo and Yamnaya-like Catacomb-Poltavka herders in the Sintashta-Potapovka-Filatovka community, probably more easily detectable in this group because of the specific temporal and geographic sampling available.

srubnaya-yamnaya-ehg-chg-ancestry
Supplementary Table 14. P values of rank=3 and admixture proportions in modelling Steppe ancestry populations as a four-way admixture of distal sources EHG, CHG, Anatolian_Neolithic and WHG using 14 outgroups.
Left populations: Steppe cluster, EHG, CHG, WHG, Anatolian_Neolithic
Right populations: Mbuti.DG, Ust_Ishim.DG, Kostenki14, MA1, Han.DG, Papuan.DG, Onge.DG, Villabruna, Vestonice16, ElMiron, Ethiopia_4500BP.SG, Karitiana.DG, Natufian, Iran_Ganj_Dareh_Neolithic.

Srubnaya ancestry shows a best fit with non-Pre-Yamnaya ancestry, i.e. with different CHG + EHG components – possibly because the more western Potapovka (ancestral to Proto-Srubnaya Pokrovka) also showed good fits for it. Srubnaya shows poor fits for Pre-Yamnaya ancestry probably because Corded Ware-like (Abashevo) genetic influence increased during its formation.

On the other hand, more eastern Corded Ware-derived groups like Sintashta and its more direct offshoot Andronovo show poor fits with this model, too, but their fits are still better than those including Pre-Yamnaya ancestry.

mlba-ehg-ancestry
Natural neighbor interpolation of non-Pre-Yamnaya EHG ancestry among Middle to Late Bronze Age populations. See full map.
mlba-chg-ancestry
Natural neighbor interpolation of non-Pre-Yamnaya CHG ancestry among Middle to Late Bronze Age populations. See full map.
mlba-anatolia-farmer-ancestry
Natural neighbor interpolation of Anatolia Neolithic ancestry among Middle to Late Bronze Age populations. See full map.
mlba-iran-chl-ancestry
Natural neighbor interpolation of Iran Chl. ancestry among Middle to Late Bronze Age populations. See full map.

NOTE For maps with actual formal stats of Corded Ware ancestry from the Early Bronze Age to the modern times, you should read the post Corded Ware ancestry in North Eurasia and the Uralic expansion instead.

The bottleneck of Proto-Indo-Iranians under R1a-Z93 was not yet complete by the time when the Sintashta-Potapovka-Filatovka community expanded with the Srubna-Andronovo horizon:

early-bronze-age-y-dna
Y-DNA haplogroups in West Eurasia during the European Early Bronze Age. See full map and see maps of cultures, ADMIXTURE, Y-DNA, and mtDNA of the Early Bronze Age.

4.4. Afanasevo

At the end of the Afanasevo culture, at least three samples show hg. Q1b (ca. 2900-2500 BC), which seemed to point to a resurgence of local lineages, despite continuity of the prototypical Pre-Yamnaya ancestry. On the other hand, Anthony (2019) makes this cryptic statement:

Yamnaya men were almost exclusively R1b, and pre-Yamnaya Eneolithic Volga-Caspian-Caucasus steppe men were principally R1b, with a significant Q1a minority.

Since the only available samples from the Khvalynsk community are R1b (x3), Q1a(x1), and R1a(x1), it seems strange that Anthony would talk about a “significant minority”, unless Q1a (potentially Q1b in the newer nomenclature) will pop up in some more individuals of those ca. 30 new to be published. Because he also mentions I2a2 as appearing in one elite burial, it seems Q1a (like R1a-M459) will not appear under elite kurgans, although it is still possible that hg. Q1a was involved in the expansion of Afanasevo to the east.

middle-bronze-age-y-dna
Y-DNA haplogroups in West Eurasia during the Middle Bronze Age. See full map and see maps of cultures, ADMIXTURE, Y-DNA, and mtDNA of the Middle Bronze Age and the Late Bronze Age.

Okunevo, which replaced Afanasevo in the Altai region, shows a majority of hg. Q1b, but also some R1b-M269 samples proper of Afanasevo, suggesting partial genetic continuity.

NOTE. Other sampled Siberian populations clearly show a variety of Q subclades that likely expanded during the Palaeolithic, such as Baikal EBA samples from Ust’Ida and Shamanka with a majority of Q1b, and hg. Q reported from Elunino, Sagsai, Khövsgöl, and also among peoples of the Srubna-Andronovo horizon (the Krasnoyarsk MLBA outlier), and in Karasuk.

From Damgaard et al. Science (2018):

(…) in contrast to the lack of identifiable admixture from Yamnaya and Afanasievo in the CentralSteppe_EMBA, there is an admixture signal of 10 to 20% Yamnaya and Afanasievo in the Okunevo_EMBA samples, consistent with evidence of western steppe influence. This signal is not seen on the X chromosome (qpAdm P value for admixture on X 0.33 compared to 0.02 for autosomes), suggesting a male-derived admixture, also consistent with the fact that 1 of 10 Okunevo_EMBA males carries a R1b1a2a2 Y chromosome related to those found in western pastoralists. In contrast, there is no evidence of western steppe admixture among the more eastern Baikal region region Bronze Age (~2200 to 1800 BCE) samples.

This Yamnaya ancestry has been also recently found to be the best fit for the Iron Age population of Shirenzigou in Xinjiang – where Tocharian languages were attested centuries later – despite the haplogroup diversity acquired during their evolution, likely through an intermediate Chemurchek culture (see a recent discussion on the elusive Proto-Tocharians).

Haplogroup diversity seems to be common in Iron Age populations all over Eurasia, most likely due to the spread of different types of sociopolitical structures where alliances played a more relevant role in the expansion of peoples. A well-known example of this is the spread of Akozino warrior-traders in the whole Baltic region under a partial N1a-VL29-bottleneck associated with the emerging chiefdom-based systems under the influence of expanding steppe nomads.

early-iron-age-y-dna
Y-DNA haplogroups in West Eurasia during the Early Iron Age. See full map and see maps of cultures, ADMIXTURE, Y-DNA, and mtDNA of the Early Iron Age and Late Iron Age.

Surprisingly, then, Proto-Tocharians from Shirenzigou pack up to 74% Yamnaya ancestry, in spite of the 2,000 years that separate them from the demise of the Afanasevo culture. They show more Yamnaya ancestry than any other population by that time, being thus a sort of Late PIE fossils not only in their archaic dialect, but also in their genetic profile:

shirenzigou-afanasievo-yamnaya-andronovo-srubna-ulchi-han

The recent intrusion of Corded Ware-like ancestry, as well as the variable admixture with Siberian and East Asian populations, both point to the known intense Old Iranian and Old/Middle Chinese contacts. The scarce Proto-Samoyedic and Proto-Turkic loans in Tocharian suggest a rather loose, probably more distant connection with East Uralic and Altaic peoples from the forest-steppe and steppe areas to the north (read more about external influences on Tocharian).

Interestingly, both R1b samples, MO12 and M15-2 – likely of Asian R1b-PH155 branch – show a best fit for Andronovo/Srubna + Hezhen/Ulchi ancestry, suggesting a likely connection with Iranians to the east of Xinjiang, who later expanded as the Wusun and Kangju. How they might have been related to Huns and Xiongnu individuals, who also show this haplogroup, is yet unknown, although Huns also show hg. R1a-Z93 (probably most R1a-Z2124) and Steppe_MLBA ancestry, earlier associated with expanding Iranian peoples of the Srubna-Andronovo horizon.

All in all, it seems that prehistoric movements explained through the lens of genetic research fit perfectly well the linguistic reconstruction of Proto-Indo-European and Proto-Uralic.

Related

Volga Basin R1b-rich Proto-Indo-Europeans of (Pre-)Yamnaya ancestry

yamnaya-expansion

New paper (behind paywall) by David Anthony, Archaeology, Genetics, and Language in the Steppes: A Comment on Bomhard, complementing in a favourable way Bomhard’s Caucasian substrate hypothesis in the current issue of the JIES.

NOTE. I have tried to access this issue for some days, but it’s just not indexed in my university library online service (ProQuest) yet. This particular paper is on Academia.edu, though, as are Bomhard’s papers on this issue in his site.

Interesting excerpts (emphasis mine):

Along the banks of the lower Volga many excavated hunting-fishing camp sites are dated 6200-4500 BC. They could be the source of CHG ancestry in the steppes. At about 6200 BC, when these camps were first established at Kair Shak III and Varfolomievka (42 and 28 on Figure 2), they hunted primarily saiga antelope around Dzhangar, south of the lower Volga, and almost exclusively onagers in the drier desert-steppes at Kair-Shak, north of the lower Volga. Farther north at the lower/middle Volga ecotone, at sites such as Varfolomievka and Oroshaemoe hunter-fishers who made pottery similar to that at Kair-Shak hunted onagers and saiga antelope in the desert-steppe, horses in the steppe, and aurochs in the riverine forests. Finally, in the Volga steppes north of Saratov and near Samara, hunter-fishers who made a different kind of pottery (Samara type) and hunted wild horses and red deer definitely were EHG. A Samara hunter-gatherer of this era buried at Lebyazhinka IV, dated 5600-5500 BC, was one of the first named examples of the EHG genetic type (Haak et al. 2015). This individual, like others from the same region, had no or very little CHG ancestry. The CHG mating network had not yet reached Samara by 5500 BC.

morgunova-eneolithic-pontic-caspian
Eneolithic settlements (1–5, 7, 10–16, 20, 22–43, 48, 50), burial grounds (6, 8–9, 17–19, 21, 47, 49) and kurgans (44–46) of the steppe Ural-Volga region: 1 Ivanovka; 2 Turganik; 3 Kuzminki; 4 Mullino; 5 Davlekanovo; 6 Sjezheye (burial ground); 7 Vilovatoe; 8 Ivanovka; 9 Krivoluchye; 10–13 LebjazhinkaI-III-IV-V; 14 Gundorovka; 15–16 Bol. Rakovka I-II; 17–18 Khvalunsk I-II; 19 Lipoviy Ovrag; 20 Alekseevka; 21 Khlopkovskiy; 22 Kuznetsovo I; 23 Ozinki II; 24 Altata; 25 Monakhov I; 26 Oroshaemoe; 27 Rezvoe; 28 Varpholomeevka; 29 Vetelki; 30 Pshenichnoe; 31 Kumuska; 32 Inyasovo; 33 Shapkino VI; 34 Russkoe Truevo I; 35 Tsaritsa I-II; 36 Kamenka I; 37 Kurpezhe-Molla; 38 Istay; 39 Isekiy; 40 Koshalak; 41 Kara-Khuduk; 42 Kair-Shak VI; 43 Kombakte; 44 Berezhnovka I-II; 45 Rovnoe; 46 Politotdelskoe; 47 burial near s. Pushkino; 48 Elshanka; 49 Novoorsk; 50 Khutor Repin. Modified from Morgunova (2014).

But before 4500 BC, CHG ancestry appeared among the EHG hunter-fishers in the middle Volga steppes from Samara to Saratov, at the same time that domesticated cattle and sheep-goats appeared. The Reich lab now has whole-genome aDNA data from more than 30 individuals from three Eneolithic cemeteries in the Volga steppes between the cities of Saratov and Samara (Khlopkov Bugor, Khvalynsk, and Ekaterinovka), all dated around the middle of the fifth millennium BC. Many dates from human bone are older, even before 5000 BC, but they are affected by strong reservoir effects, derived from a diet rich in fish, making them appear too old (Shishlina et al 2009), so the dates I use here accord with published and unpublished dates from a few dated animal bones (not fish-eaters) in graves.

Only three individuals from Khvalynsk are published, and they were first published in a report that did not mention the site in the text (Mathieson et al. 2015), so they went largely unnoticed. Nevertheless, they are crucial for understanding the evolution of the Yamnaya mating network in the steppes. They were mentioned briefly in Damgaard et al (2018) but were not graphed. They were re-analyzed and their admixture components were illustrated in a bar graph in Wang et al (2018: figure 2c), but they are not the principal focus of any published study. All of the authors who examined them agreed that these three Khvalynsk individuals, dated about 4500 BC, showed EHG ancestry admixed substantially with CHG, and not a trace of Anatolian Farmer ancestry, so the CHG was a Hotu-Cave or Kotias-Cave type of un-admixed CHG. The proportion of CHG in the Wang et al. (2018) bar graphs is about 20-30% in two individuals, substantially less CHG than in Yamnaya; but the third Khvalynsk individual had more than 50% CHG, like Yamnaya. The ca. 30 additional unpublished individuals from three middle Volga Eneolithic cemeteries, including Khvalynsk, preliminarily show the same admixed EHG/CHG ancestry in varying proportions. Most of the males belonged to Y-chromosome haplogroup R1b1a, like almost all Yamnaya males, but Khvalynsk also had some minority Y-chromosome haplogroups (R1a, Q1a, J, I2a2) that do not appear or appear only rarely (I2a2) in Yamnaya graves.

eneolithic-steppes
Pontic-Caspian steppe and neighbouring groups in the Neolithic. See full map.

Wang et al. (2018) discovered that this middle Volga mating network extended down to the North Caucasian steppes, where at cemeteries such as Progress-2 and Vonyuchka, dated 4300 BC, the same Khvalynsk-type ancestry appeared, an admixture of CHG and EHG with no Anatolian Farmer ancestry, with steppe-derived Y-chromosome haplogroup R1b. These three individuals in the North Caucasus steppes had higher proportions of CHG, overlapping Yamnaya. Without any doubt, a CHG population that was not admixed with Anatolian Farmers mated with EHG populations in the Volga steppes and in the North Caucasus steppes before 4500 BC. We can refer to this admixture as pre-Yamnaya, because it makes the best currently known genetic ancestor for EHG/CHG R1b Yamnaya genomes. The Progress-2 individuals from North Caucasus steppe graves lived not far from the pre-Maikop farmers of the Belaya valley, but they did not exchange mates, according to their DNA.

The hunter-fisher camps that first appeared on the lower Volga around 6200 BC could represent the migration northward of un-admixed CHG hunter-fishers from the steppe parts of the southeastern Caucasus, a speculation that awaits confirmation from aDNA. After 5000 BC domesticated animals appeared in these same sites in the lower Volga, and in new ones, and in grave sacrifices at Khvalynsk and Ekaterinovka. CHG genes and domesticated animals flowed north up the Volga, and EHG genes flowed south into the North Caucasus steppes, and the two components became admixed. After approximately 4500 BC the Khvalynsk archaeological culture united the lower and middle Volga archaeological sites into one variable archaeological culture that kept domesticated sheep, goats, and cattle (and possibly horses). In my estimation, Khvalynsk might represent the oldest phase of PIE.

eneolithic-early-steppes
Pontic-Caspian steppe and neighbouring groups in the Early Eneolithic. See full map.

Anatolian Farmer ancestry and Yamnaya origins

The Eneolithic Volga-North Caucasus mating network (Khvalynsk/Progress-2 type) exhibited EHG/CHG admixtures and Y-chromosome haplogroups similar to Yamnaya, but without Yamnaya’s additional Anatolian Farmer ancestry. (…)

Like the Mesolithic and Neolithic populations here, the Eneolithic populations of Dnieper-Donets II type seem to have limited their mating network to the rich, strategic region they occupied, centered on the Rapids. The absence of CHG shows that they did not mate frequently if at all with the people of the Volga steppes, a surprising but undeniable discovery. Archaeologists have seen connections in ornament types and in some details of funeral ritual between Dnieper-Donets cemeteries of the Mariupol-Nikol’skoe type and cemeteries in the middle Volga steppes such as Khvalynsk and S’yez’zhe (Vasiliev 1981:122-123). Also their cranio-facial types were judged to be similar (Bogdanov and Khokhlov 2012:212). So it it surprising that their aDNA does not indicate any genetic admixture with Khvalynsk or Progress-2. Also, neither they nor the Volga steppe Eneolithic populations showed any Anatolian Farmer ancestry. (…)

All three of the steppe-admixed exceptions were from the Varna region (Mathieson et al. 2018). One of them was the famous “golden man’ at Varna (Krause et al. 2016), Grave 43, whose steppe ancestry was the most doubtful of the three. If he had steppe ancestry, it was sufficiently distant (five+ generations before him) that he was not a statistically significant outlier, but he was displaced in the steppe direction, away from the central values of the majority of typical Anatolian Farmers at Varna and elsewhere. The other two, at Varna (grave 158, a 5-7-year-old girl) and Smyadovo (grave 29, a male 20-25 years old), were statistically significant outliers who had recent steppe ancestry (consistent with grandparents or great-grandparents) of the EHG/CHG Khvalynsk/Progress-2 type, not of the Dnieper Rapids EHG/WHG type.

(…) I believe that the Suvorovo-Cernavoda I movement into the lower Danube valley and the Balkans about 4300 BC separated early PIE-speakers (pre-Anatolian) from the steppe population that stayed behind in the steppes and that later developed into late PIE and Yamnaya.

This archaeological transition marked the breakdown of the mating barrier between steppe and Anatolian Farmer mating networks. After this 4300-4200 BC event, Anatolian Farmer ancestry began to pop up in the steppes. The currently oldest sample with Anatolian Farmer ancestry in the steppes in an individual at Aleksandriya, a Sredni Stog cemetery on the Donets in eastern Ukraine. Sredni Stog has often been discussed as a possible Yamnaya ancestor in Ukraine (Anthony 2007: 239- 254). The single published grave is dated about 4000 BC (4045– 3974 calBC/ 5215±20 BP/ PSUAMS-2832) and shows 20% Anatolian Farmer ancestry and 80% Khvalynsk-type steppe ancestry (CHG&EHG). His Y-chromosome haplogroup was R1a-Z93, similar to the later Sintashta culture and to South Asian Indo-Aryans, and he is the earliest known sample to show the genetic adaptation to lactase persistence (I3910-T). Another pre-Yamnaya grave with Anatolian Farmer ancestry was analyzed from the Dnieper valley at Dereivka, dated 3600-3400 BC (grave 73, 3634–3377 calBC/ 4725±25 BP/ UCIAMS-186349). She also had 20% Anatolian Farmer ancestry, but she showed less CHG than Aleksandriya and more Dereivka-1 ancestry, not surprising for a Dnieper valley sample, but also showing that the old fifth-millennium-type EHG/WHG Dnieper ancestry survived into the fourth millennium BC in the Dnieper valley (Mathieson et al. 2018).

late-eneolithic-repin
Pontic-Caspian steppe and neighbouring groups in the Late Eneolithic. See full map.

Probably, late PIE (Yamnaya) evolved in the same part of the steppes—the Volga-Caucasus steppes between the lower Don, the lower and middle Volga, and the North Caucasus piedmont—where early PIE evolved, and where appropriate EHG/CHG admixtures and Y-chromosome haplogroups were seen already in the Eneolithic (without Anatolian Farmer). There have always been archaeologists who argued for an origin of Yamnaya in the Volga steppes, including Gimbutas (1963), Merpert (1974), and recently Morgunova (2014), who argued that this was where Repin-type ceramics, an important early Yamnaya pottery type, first appeared in dated contexts before Yamnaya, about 3600 BC. The genetic evidence is consistent with Yamnaya EHG/CHG origins in the Volga-Caucasus steppes. Also, if contact with the Maikop culture was a fundamental cause of the innovations in transport and metallurgy that defined the Yamnaya culture, then the lower Don-North Caucasus-lower Volga steppes, closest to the North Caucasus, would be where the earliest phase is expected.

I would still guess that the Darkveti-Meshoko culture and its descendant Maikop culture established the linguistic ancestor of the Northwest Caucasian languages in approximately the region where they remained. I also accept the general consensus that the appearance of the hierarchical Maikop culture about 3600 BC had profound effects on pre-Yamnaya and early Yamnaya steppe cultures. Yamnaya metallurgy borrowed from the Maikop culture two-sided molds, tanged daggers, cast shaft hole axes with a single blade, and arsenical copper. Wheeled vehicles might have entered the steppes through Maikop, revolutionizing steppe economies and making Yamnaya pastoral nomadism possible after 3300 BC.

For those who still hoped that Proto-Indo-Europeans of Yamnaya/Afanasievo ancestry from the Don-Volga region were associated with the expansion of hg. R1a-M417, in a sort of mythical “R1-rich” Indo-European society, it seems this is going to be yet another prediction based on ancestry magic that goes wrong.

Proto-Indo-Europeans were, however, associated with other subclades beyond R1b-M269, probably (as I wrote recently) R1b-V1636, I2a-L699, Q1a-M25, and R1a-YP1272, but also interestingly some J subclade, so let’s see what surprises the new study on Khvalynsk and Yamnaya settlers from the Carpathian Basin brings…

On the bright side, it is indirectly confirmed that late Sredni Stog formed part of the neighbouring Corded Ware-like populations of ca. 20-30%+ Anatolian farmer ancestry that gave Yamnaya its share (ca. 6-10%), relative to the comparatively unmixed Khvalynsk and late Repin population (as shown by Afanasevo).

In this steppe mating network that opened up after the Khvalynsk expansion, the increasing admixture of Anatolian farmer-related ancestry in Yamnaya from east (ca. 2-10%) to west (ca. 6-15%) points to an exogamy of late Repin males in their western/south-western regions with populations around the Don River basin and beyond (and endogamy within the Yamnaya community), in an evolution relevant for language expansions and language contacts during the Late Eneolithic.

NOTE. “Mating network” is my new preferred term for “ancestry”. Also great to see scholars finally talk about “Pre-Yamnaya” ancestry, which – combined with the distinction of Yamnaya from Corded Ware ancestry – will no doubt help differentiate fine-scale population movements of steppe- and forest-steppe-related populations.

north-pontic-kvityana-dereivka-repin
Modified from Rassamakin (1999), adding red color to Repin expansion. The system of the latest Eneolithic Pointic cultures and the sites of the Zhivotilovo-Volchanskoe type: 1) Volchanskoe; 2) Zhivotilovka; 3) Vishnevatoe; 4) Koisug.

The whole issue of the JIES is centered on Caucasian influences on Early PIE as an Indo-Uralic dialect, and this language contact/substrate is useful to locate the most likely candidates for the Northeast and Northwest Caucasian and the Proto-Indo-European homelands.

On the other hand, it would also be interesting to read a discussion of how this Volga homeland of Middle PIE and Don-Volga-Ural homeland of Late PIE would be reconciled with the known continuous contacts of Uralic with Middle and Late PIE (see here) to locate the most likely Proto-Uralic homeland.

Especially because Corded Ware fully replaced all sub-Neolithic groups to the north and east of Khvalynsk/Yamnaya, like Volosovo, so no other population neighbouring Middle and Late Proto-Indo-Europeans survived into the Bronze Age…

EDIT: For those new to this blog, this information on unpublished samples from the Volga River basin is yet another confirmation of Khokhlov’s report on the R1b-L23 samples from Yekaterinovka, and its confirmation by a co-author of The unique elite Khvalynsk male from a Yekaterinovskiy Cape burial, apart from more support to the newest data placing Yekaterinovka culturally and probably chronologically between Samara and Khvalynsk.

Related

Yekaterinovsky Cape, a link between the Samara culture and early Khvalynsk

ekaterinovsky-cape

We already had conflicting information about the elite individual from the Yekaterinovsky Cape and the materials of his grave, which seemed quite old:

For the burial of 45 in the laboratory of the University of Pennsylvania, a 14C date was obtained: PSUAMS-2880 (Sample ID 16068)> 30 kDa gelatin Russia. 12, Ekaterinovka Grave 45 14C age (BP) 6325 ± 25 δ 13C (‰) –23.6 δ15 N (‰) 14.5. The results of dating suggest chronological proximity with typologically close materials from Yasinovatsky and Nikolsky burial grounds (Telegini et al. 2001: 126). The date obtained also precedes the existing dates for the Khvalynsk culture (Morgunova 2009: 14–15), which, given the dominance of Mariupol traits of the burial rite and inventory, confirms its validity. However, the date obtained for human bones does not exclude the possibility of a “reservoir effect” when the age can increase three or more centuries (Shishlin et al. 2006: 135–140).

Now the same date is being confirmed by the latest study published on the site, by Korolev, Kochkina, and Stachenkov (2019) and it seems it is really going to be old. Abstract (in part the official one, in part newly translated for clarity):

For the first time, pottery of the Early Eneolithic burial ground Ekaterinovsky Cape is published. Ceramics were predominantly located on the sacrificial sites in the form of compact clusters of fragments. As a rule, such clusters were located above the burials, sometimes over the burials, some were sprinkled with ocher. The authors have identified more than 70 vessels, some of which have been partially reconstructed. Ceramic was made with inclusion of the crushed shell into molding mass. The rims of vessels had the thickened «collar»; the bottoms had a rounded shape. The ornament was located on the rims and the upper part of the potteries. Fully decorated vessels are rare. The vessels are ornamented with prints of comb and rope stamps, with small pits. A particularity of ceramics ornamentation is presented by the imprints of soft stamps (leather?) or traces of leather form for the making of vessels. The ornamentation, made up of «walking comb» and incised lines, was used rarely as well as the belts of pits made decoration under «collar» of a rim. Some features of the ceramics decoration under study relate it with ceramics of the Khvalynsk culture. The ceramics of Ekaterinovsky Cape burial ground is attributed by the authors to the Samara culture. The ceramic complex under study has proximity to the ceramics from Syezzhe burial ground and the ceramics of the second phase of Samara culture. The chronological position is determined by the authors as a later period than the ceramics from the Syezzhe burial ground, and earlier than the chronological position of ceramics of the Ivanovka stage of the Samara culture and the Khvalynsk culture.

ekaterinovsky-cape-pottery
Ceramics from Ekaterinovsky Cape burial ground. 1–2, 4–5, 7–11 – ceramics from aggregations; 3, 6 – ceramics from the cultural layer.

More specifically:

Based on ceramic fragments from a large vessel from a cluster of sq.m. 14, the date received was: SPb-2251–5673 ± 120 BP. The second date was obtained in fragments from the aggregation [see picture above] from the cluster of sq.m. 45–46: SPb-2252–6372 ± 100 BP. The difference in dating indicates that the process of determining the chronology of the burial ground is far from complete, although we note that the earlier date almost coincided with the date obtained from the human bone from individual 45 (Korolev, Kochkina, Stashenkov, 2018, p. 300).

Therefore, the ceramics of the burial ground Ekaterinovsky Cape possess an originality that determines the chronological position of the burial ground between the earliest materials of the burial type in Syezzhe and the Khvalynsk culture. Techno-typological features of dishes make it possible to attribute it to the Samara culture at the stage preceding the appearance of Ivanovska-Khvalynsk ceramics.

It seems that this site showed cultural influences from the upstream region near the Kama-Vyatka interfluve, too, according to Korolev, Kochkina, Stashenkov, and Khokhlov (2018):

In 2017, excavation of burial ground Ekaterinovsky Cape were continued, located in the area of the confl uence of the Bezenchuk River in the Volga River. During the new excavations, 14 burials were studied. The skeleton of the buried were in a position elongated on the back, less often – crooked on the back with knees bent at the knees. In one burial (No. 90), a special position of the skeleton was recorded. In the burial number 90 in the anatomical order, parts of the male skeleton. This gave grounds for the reconstruction of his original position in a semi-sitting position with the support of elbows on the bottom of the pit. Noteworthy inventory: on the pelvic bones on the left lay a bone spoon, near the right humerus, the pommel of a cruciform club was found. A conclusion is made about the high social status of the buried. The results of the analysis of the burial allow us to outline the closest circle of analogies in the materials of Khvalynsky I and Murzikhinsky burial grounds.

Important sites mentioned in both papers and in this text:

To sum up, it seems that the relative dates we have used until now have to be corrected: older Khvalynsk I Khvalynsk II individuals, supposedly dated ca. 5200-4000 BC (most likely after 4700 BC), and younger Yekaterinovsky individuals, supposedly of the fourth quarter of the 5th millennium (ca. 4250-4000 BC), are possibly to be considered, in fact, roughly reversed, if not chronologically, at least culturally speaking.

Interestingly, this gives a new perspective to the presence of a rare fish- or reptile-headed pommel-scepter, which would be natural in a variable period of expansion of the horse and horse-related symbolism, a cultural trait rooted in the Samara culture attested in Syezzhe before the unification of the symbol of power under the ubiquitous Khvalynsk-Suvorovo horse-headed scepters and related materials.

ekaterinovsky-cape-pommel-mace
Ekaterinovsky Cape Burial Ground. Inventory of the burial no 90: 1, 2 – stone pommel of the mace; 3, 4 – bone article.

The Khvalynsk chieftain

If the reported lineages from Yekaterinovsky Cape are within the R1b-P297 tree, but without further clades, as Yleaf comparisons may suggest, there is not much change to what we have, and R1b-M269 could actually represent a part of the local population, but also incomers from the south (e.g. the north Caspian steppe hunter-gatherers like Kairshak), the east (with hunter-gatherer pottery), or the west near the Don River (in contact with Mariupol-related cultures, as the authors inferred initially from material culture).

Just like R1a-M417 became incorporated into the Sredni Stog groups after the Novodanilovka-Suvorovo expansion, probably as incoming hunter-gatherer pottery groups from the north admixing with peoples of “Steppe ancestry”, R1b-M269 lineages might have expanded explosively only during the Repin expansion, and maybe (like R1b-L51 later) they formed just a tiny part of the clans that dominated the steppe during the Khvalynsk-Novodanilovka community.

On the other hand, the potential finding of various R1b-M269/L23 samples in Yekaterinovsky Cape (including an elite individual) would suggest now, as it was supported in the original report by Mathieson et al. (2015), that these ancient R1b lineages found in the Volga – Ural region are in fact most likely all R1b-M269 without enough coverage to obtain proper SNP calls, which would simplify the picture of Neolithic expansions (yet again). From the supplementary materials:

10122 / SVP35 (grave 12). Male (confirmed genetically), age 20-30, positioned on his back with raised knees, with 293 copper artifacts, mostly beads, amounting to 80% of the copper objects in the combined cemeteries of Khvalynsk I and II. Probably a high-status individual, his Y-chromosome haplotype, R1b1, also characterized the high-status individuals buried under kurgans in later Yamnaya graves in this region, so he could be regarded as a founder of an elite group of patrilineally related families. His MtDNA haplotype H2a1 is unique in the Samara series.

khvalynsk-cemetery
Khvalynsk cemetery and grave gifts. Grave 90 contained copper beads and rings, a harpoon, flint blades, and a bird-bone tube. Both graves (90 and 91) were partly covered by Sacrificial Deposit 4 with the bones from a horse, a sheep, and a cow. Center: grave goods from the Khvalynsk cemetery-copper rings and bracelets, polished stone mace heads, polished stone bracelet, Cardium shell ornaments, boars tusk chest ornaments, flint blades, and bifiacial projectile points. Bottom: shell-tempered pottery from the Khvalynsk cemetery. After Agapov, Vasiliev, and Pestrikova 1990; and Ryndina 1998, Figure 31. Modified from Anthony (2007).

This remarkable Khvalynsk chieftain, whose rich assemblage may correspond to the period of domination of the culture all over the Pontic-Caspian steppes, has been consistently reported as of hg. R1b-L754 in all publications, including Wang et al. (2018/2019) tentative SNP calls in the supplementary materials (obtained with Yleaf, as the infamous Narasimhan et al. 2018 samples), but has been variously reported by amateurs as within the R1b-M73, R1b-V88, or (lately) R1b-V1636 trees, which makes it unlikely that quality of the sample is allowing for a proper SNP call.

The fact that Mathieson et al. (2015) considered it a member of the R1b-M269 clans appearing later in Yamna seems on point right now, especially if samples from Yekaterinovka are all within this tree. The relevance of R1b-L23 in the expansion of Repin and Yamna is reminiscent of the influence of successful clans among Yamna offshoots, such as Bell Beakers, and among Bell Beaker offshoots during the Bronze Age all over Europe.

Taking these younger expansions as example, it seems quite likely based on cultural links that (at least part of) the main clans of Khvalynsk were of R1b-M269 lineage, stemming from a R1b-dominated Samara culture, in line with the known succeeding expansions and the expected strictly patriarcal and patrilineal society of Proto-Indo-Europeans, which would have exacerbated the usual reduction in Y-chromosome haplogroup variability that happens during population expansions, and the aversion towards foreign groups while the culture lasted.

pontic-steppe-neolithic
Cultures of the Pontic-Caspian steppes and forest-steppes and surrounding areas during the Neolithic.

The finding of R1b-L23 in Yekaterinovka, associated with the Samara culture, before or during the Khvalynsk expansion, and close to the Khvalynsk site, would make this Khvalynsk chieftain most likely a member of the M269 tree (paradoxically, the only R1b-L754 branch amateurs have not yet reported for it). Similarly, the sample of a “Samara hunter-gatherer” of Lebyazhinka, of hg. R1b-P297, could also be under this tree, just like most R1b-M269 from Yamna are downstream from R1b-L23, and most reported R1b-M269 or R1b-L23 from Bell Beakers are under R1b-L151.

On the other hand, we know of the shortcomings of attributing a haplogroup expansion to the best known rulers, such as the famous lineages previously wrongly attributed to Niall of the Nine Hostages or Genghis Khan. The known presence of R1b-V1636 up to modern Greeks would be in line with an ancient steppe expansion that we know will show up during the Neolithic, although it could also be a sign of a more recent migration from the Caucasus. The presence of a sister clade of R1b-L23, R1b-PF7562, among modern Balkan populations, may also be attributed to a pre-Yamna steppe expansion.

y-dna-khvalynsk
Y-DNA samples from Khvalynsk and neighbouring cultures. See full version here.

On SNP calls

I reckon that even informal reports on SNP calls, like any other analyses, should be offered in full: not only with a personal or automatic estimation of the result, but with a detailed explanation of the good, dubious, and bad calls, alternatives to that SNP estimation, and a motivated reasoning of why one branch should be preferred over others. Downloading a sample and giving an instruction using a free software tool is never enough, as it became crystal clear recently for the hilariously biased and flawed qpAdm reports on Dutch Bell Beakers as the ‘missing link’ between Corded Ware and Bell Beakers…

Another example I can recall is the report of a R1a-Z93 subclade in the R1a-M417 sample ca. 4000 BC from Alexandria, which seems rather unlikely, seeing how this subclade must have split and expanded explosively with R1a-Z645 to the east with eastern Corded Ware groups, i.e. 1,000 years later, just like Z282 lineages expanded mainly to the north-east. But then again, as with the Khvalynsk chieftain, I have only seen indirect reports of that supposed SNP (including Y26+!), so we should just stick with its officially reported R1a-M417 lineage. This upstream haplogroup was, in fact, repeated with Yleaf’s tentative estimates in Wang et al. (2019) supplementary materials…

The combination of inexperienced, biased, or simply careless design, analyses, and reports, including SNP calls and qpAdm analyses (whether in forums or publications), however well-intentioned (or not) they might be, are hindering a proper analysis of data, adding to the difficulties we already have due to the scarcity of samples, their limited coverage, and the lack of proper context.

Some people like to repeat ad nauseam that archaeology and/or linguistics are ‘not science’ whenever they don’t fit their beliefs and myths based on haplogroup and/or ancestry. But it’s becoming harder and harder to rely on certain genetic data, too, and on their infinite changing interpretations, much more than it is to rely on linguistic and archaeological research, including data, assessments, and discussions that are open for anyone to review…if one is truly interested in them.

The genetic and cultural barrier of the Pontic-Caspian steppe – forest-steppe ecotone

steppe-forest-steppe-biomes

We know that the Caucasus Mountains formed a persistent prehistoric barrier to cultural and population movements. Nevertheless, an even more persistent frontier to population movements in Europe, especially since the Neolithic, is the Pontic-Caspian steppe – forest-steppe ecotone.

Like the Caucasus, this barrier could certainly be crossed, and peoples and cultures could permeate in both directions, but there have been no massive migrations through it. The main connection between both regions (steppe vs. forest-steppe/forest zone) was probably through its eastern part, through the Samara region in the Middle Volga.

The chances of population expansions crossing this natural barrier anywhere else seem quite limited, with a much less porous crossing region in the west, through the Dnieper-Dniester corridor.

A Persistent ecological and cultural frontier

It is very difficult to think about any culture that transgressed this persistent ecological and cultural frontier: many prehistoric and historical steppe pastoralists did appear eventually in the neighbouring forest-steppe areas during their expansions (e.g. Yamna, Scythians, or Turks), as did forest groups who permeated to the south (e.g. Comb Ware, GAC, or Abashevo), but their respective hold in foreign biomes was mostly temporary, because their cultures had to adapt to the new ecological environment. Most if not all groups originally from a different ecological niche eventually disappeared, subjected to renewed demographic pressure from neighbouring steppe or forest populations…

The Samara region in the Middle Volga may be pointed out as the true prehistoric link between forests and steppes (see David Anthony’s remarks), something reflected in its nature as a prehistoric sink in genetics. This strong forest – forest-steppe – steppe connection was seen in the Eurasian technocomplex, during the expansion of hunter-gatherer pottery, in the expansion of Abashevo peoples to the steppes (in one of the most striking cases of population admixture in the area), with Scythians (visible in the intense contacts with Ananyino), and with Turks (Volga Turks).

steppe-forest-steppe-europe
Simplified map of the distribution of steppes and forest-steppes (Pontic and Pannonian) and xeric grasslands in Eastern Central Europe (with adjoining East European ranges) with their regionalisation as used in the review (Northern—Pannonic—Pontic). Modified from Kajtoch et al. (2016).

Before the emergence of pastoralism, the cultural contacts of the Pontic region (i.e. forest-steppes) with the Baltic were intense. In fact, the connection of the north Pontic area with the Baltic through the Dnieper-Dniester corridor and the Podolian-Volhynian region is essential to understand the spread of peoples of post-Maglemosian and post-Swiderian cultures (to the south), hunter-gatherer pottery (to the north), TRB (to the south), Late Trypillian groups (north), GAC (south), or Comb Ware (south) (see here for Eneolithic movements), and finally steppe ancestry and R1a-Z645 with Corded Ware (north). After the complex interaction of TRB, Trypillia, GAC, and CWC during the expansion of late Repin, this traditional long-range connection is lost and only emerges sporadically, such as with the expansion of East Germanic tribes.

A barrier to steppe migrations into northern Europe

One may think that this barrier was more permeable, then, in the past. However, the frontier is between steppe and forest-steppe ecological niches, and this barrier evolved during prehistory due to climate changes. The problem is, before the drought that began ca. 4000 BC and increased until the Yamna expansion, the steppe territory in the north Pontic region was much smaller, merely a strip of coastal land, compared to its greater size ca. 3300 BC and later.

This – apart from the cultural and technological changes associated with nomadic pastoralism – justifies the traditional connection of the north Pontic forest-steppes to the north, broken precisely after the expansion of Khvalynsk, as the north Pontic area became gradually a steppe region. The strips of north Pontic and Azov steppes and Crimea seem to have had stronger connections to the Northern Caucasus and Northern Caspian steppes than with the neighbouring forest-steppe areas during the Upper Palaeolithic, Mesolithic, and Neolithic.

NOTE. We still don’t know the genetic nature of Mikhailovka or Ezero, steppe-related groups possibly derived from Novodanilovka and Suvorovo close to the Black Sea (which possibly include groups from the Pannonian plains), and how they compare to neighbouring typically forest-steppe cultures of the so-called late Sredni Stog groups, like Dereivka or partly Kvityana.

steppe-forest-steppe-migration-routes
Typical migration routes through European steppes and forest-steppes. Red line represents the persistent cultural and genetic barrier, with the latest evolution in steppe region represented by the shift from dashed line to the north. Arrows show the most common population movements. Modified from Kajtoch et al. (2016).

Despite the Pontic-Caspian steppes and forest-steppes neighbouring each other for ca. 2,000 km, peoples from forested and steppe areas had an obvious advantage in their own regions, most likely due to the specialization of their subsistence economy. While this is visible already in Palaeolithic and Mesolithic hunter-gatherers, the arrival of the Neolithic package in the Pontic-Caspian region incremented the difference between groups, by spreading specialized animal domestication. The appearance of nomadic pastoralism adapted to the steppe, eventually including the use of horses and carts, made the cultural barrier based on the economic know-how even stronger.

Even though groups could still adapt and permeate a different territory (from steppe to forest-steppe/forest and vice-versa), this required an important cultural change, to the extent that it is eventually complicated to distinguish these groups from neighbouring ones (like north-west Pontic Mesolithic or Neolithic groups and their interaction with the steppes, Trypillia-Usatovo, Scythians-Thracians, etc.). In fact, this steppe – forest-steppe barrier is also seen to the east of the Urals, with the distinct expansion of Andronovo and Seima-Turbino/Andronovo-like horizons, which seem to represent completely different ethnolinguistic groups.

As a result of this cultural and genetic barrier, like that formed by the Northern Caucasus:

1) No steppe pastoralist culture (which after the emergence of Khvalynsk means almost invariably horse-riding, chariot-using nomadic herders who could easily pasture their cows in the huge grasslands without direct access to water) has ever been successful in spreading to the north or north-west into northern Europe, until the Mongols. No forest culture has ever been successful in expanding to the steppes, either (except for the infiltration of Abashevo into Sintashta-Potapovka).

2) Corded Ware was not an exception: like hunter-gatherer pottery before it (and like previous population movements of TRB, late Trypillia, GAC, Comb Ware or Lublin-Volhynia settlers) their movements between the north Pontic area and central Europe happened through forest-steppe ecological niches due to their adaptation to them. There is no reason to support a direct connection of CWC with true steppe cultures.

3) The so-called “Steppe ancestry” permeated the steppe – forest-steppe ecotone for hundreds of years during the 5th and early 4th millennium BC, due to the complex interaction of different groups, and probably to the aridization trend that expanded steppe (and probably forest-steppe) to the north. Language, culture, and paternal lineages did not cross that frontier, though.

EDIT (4 FEB 2019): Wang et al. is out in Nature Communications. They deleted the Yamna Hungary samples and related analyses, but it’s interesting to see where exactly they think the trajectory of admixture of Yamna with European MN cultures fits best. This path could also be inferred long ago from the steppe connections shown by the Yamna Hungary -> Bell Beaker evolution and by early Balkan samples:

wang-yamna-connection
Prehistoric individuals projected onto a PCA of 84 modern-day West Eurasian populations (open symbols). Dashed arrows indicate trajectories of admixture: EHG—CHG (petrol), Yamnaya—Central European MN (pink), Steppe—Caucasus (green), and Iran Neolithic—Anatolian Neolithic (brown). Modified from the original, a red circle has been added to the Yamna-Central European MN admixture.

Related

ASoSaH Reread (II): Y-DNA haplogroups among Uralians (apart from R1a-M417)

corded-ware-yamna-ancestry

This is mainly a reread of from Book Two: A Game of Clans of the series A Song of Sheep and Horses: chapters iii.5. Early Indo-Europeans and Uralians, iv.3. Early Uralians, v.6. Late Uralians and vi.3. Disintegrating Uralians.

“Sredni Stog”

While the true source of R1a-M417 – the main haplogroup eventually associated with Corded Ware, and thus Uralic speakers – is still not known with precision, due to the lack of R1a-M198 in ancient samples, we already know that the Pontic-Caspian steppes were probably not it.

We have many samples from the north Pontic area since the Mesolithic compared to the Volga-Ural territory, and there is a clear prevalence of I2a-M223 lineages in the forest-steppe area, mixed with R1b-V88 (possibly a back-migration from south-eastern Europe).

R1a-M459 (xR1a-M198) lineages appear from the Mesolithic to the Chalcolithic scattered from the Baltic to the Caucasus, from the Dniester to Samara, in a situation similar to haplogroups Q1a-M25 and R1b-L754, which supports the idea that R1a, Q1a, and R1b expanded with ANE ancestry, possibly in different waves since the Epipalaeolithic, and formed the known ANE:EHG:WHG cline.

y-dna-khvalynsk
Y-DNA samples from Khvalynsk and neighbouring cultures. See full version.

The first confirmed R1a-M417 sample comes from Alexandria, roughly coinciding with the so-called steppe hiatus. Its emergence in the area of the previous “early Sredni Stog” groups (see the mess of the traditional interpretation of the north Pontic groups as “Sredni Stog”) and its later expansion with Corded Ware supports Kristiansen’s interpretation that Corded Ware emerged from the Dnieper-Dniester corridor, although samples from the area up to ca. 4000 BC, including the few Middle Eneolithic samples available, show continuity of hg. I2a-M223 and typical Ukraine Neolithic ancestry.

NOTE. The further subclade R1a-Z93 (Y26) reported for the sample from Alexandria seems too early, given the confidence interval for its formation (ca. 3500-2500 BC); even R1a-Z645 could be too early. Like the attribution of the R1b-L754 from Khvalynsk to R1b-V1636 (after being previously classifed as of Pre-V88 and M73 subclade), it seems reasonable to take these SNP calls with a pinch of salt: especially because Yleaf (designed to look for the furthest subclade possible) does not confirm for them any subclade beyond R1a-M417 and R1b-L754, respectively.

The sudden appearance of “steppe ancestry” in the region, with the high variability shown by Ukraine_Eneolithic samples, suggests that this is due to recent admixture of incoming foreign peoples (of Ukraine Neolithic / Comb Ware ancestry) with Novodanilovka settlers.

The most likely origin of this population, taking into account the most common population movements in the area since the Neolithic, is the infiltration of (mainly) hunter-gatherers from the forest areas. That would confirm the traditional interpretation of the origin of Uralic speakers in the forest zone, although the nature of Pontic-Caspian settlers as hunter-gatherers rather than herders make this identification today fully unnecessary (see here).

EDIT (3 FEB 2019): As for the most common guesstimates for Proto-Uralic, roughly coinciding with the expansion of this late Sredni Stog community (ca. 4000 BC), you can read the recent post by J. Pystynen in Freelance Reconstruction, Probing the roots of Samoyedic.

eneolithic-ukraine-corded-ware
Late Sredni Stog admixture shows variability proper of recent admixture of forest-steppe peoples with steppe-like population. See full version here.

NOTE. Although my initial simplistic interpretation (of early 2017) of Comb Ware peoples – traditionally identified as Uralic speakers – potentially showing steppe ancestry was probably wrong, it seems that peoples from the forest zone – related to Comb Ware or neighbouring groups like Lublyn-Volhynia – reached forest-steppe areas to the south and eventually expanded steppe ancestry into east-central Europe through the Volhynian Upland to the Polish Upland, during the late Trypillian disintegration (see a full account of the complex interactions of the Final Eneolithic).

The most interesting aspect of ascertaining the origin of R1a-M417, given its prevalence among Uralic speakers, is to precisely locate the origin of contacts between Late Proto-Indo-European and Proto-Uralic. Traditionally considered as the consequence of contacts between Middle and Upper Volga regions, the most recent archaeological research and data from ancient DNA samples has made it clear that it is Corded Ware the most likely vector of expansion of Uralic languages, hence these contacts of Indo-Europeans of the Volga-Ural region with Uralians have to be looked for in neighbours of the north Pontic area.

sredni-stog-repin-contacts
Sredni Stog – Repin contacts representing Uralic – Late Indo-European contacts were probably concentrated around the Don River.

My bet – rather obvious today – is that the Don River area is the source of the earliest borrowings of Late Uralic from Late Indo-European (i.e. post-Indo-Anatolian). The borrowing of the Late PIE word for ‘horse’ is particularly interesting in this regard. Later contacts (after the loss of the initial laryngeal) may be attributed to the traditionally depicted Corded Ware – Yamna contact zone in the Dnieper-Dniester area.

NOTE. While the finding of R1a-M417 populations neighbouring R1b-L23 in the Don-Volga interfluve would be great to confirm these contacts, I don’t know if the current pace of more and more published samples will continue. The information we have right now, in my opinion, suffices to support close contacts of neighbouring Indo-Europeans and Uralians in the Pontic-Caspian area during the Late Eneolithic.

Classical Corded Ware

After some complex movements of TRB, late Trypillia and GAC peoples, Corded Ware apparently emerged in central-east Europe, under the influence of different cultures and from a population that probably (at least partially) stemmed from the north Pontic forest-steppe area.

Single Grave and central Corded Ware groups – showing some of the earliest available dates (emerging likely ca. 3000/2900 BC) – are as varied in their haplogroups as it is expected from a sink (which does not in the least resemble the Volga-Ural population):

Interesting is the presence of R1b-L754 in Obłaczkowo, potentially of R1b-V88 subclade, as previously found in two Central European individuals from Blätterhole MN (ca. 3650 and 3200 BC), and in the Iron Gates and north Pontic areas.

Haplogroups I2a and G have also been reported in early samples, all potentially related to the supposed Corded Ware central-east European homeland, likely in southern Poland, a region naturally connected to the north Pontic forest-steppe area and to the expansion of Neolithic groups.

corded-ware-haplogroups
Y-DNA samples from early Corded Ware groups and neighbouring cultures. See full version.

The true bottlenecks under haplogroup R1a-Z645 seem to have happened only during the migration of Corded Ware to the east: to the north into the Battle Axe culture, mainly under R1a-Z282, and to the south into Middle Dnieper – Fatyanovo-Balanovo – Abashevo, probably eventually under R1a-Z93.

This separation is in line with their reported TMRCA, and supports the split of Finno-Permic from an eastern Uralic group (Ugric and Samoyedic), although still in contact through the Russian forest zone to allow for the spread of Indo-Iranian loans.

This bottleneck also supports in archaeology the expansion of a sort of unifying “Corded Ware A-horizon” spreading with people (disputed by Furholt), the disintegrating Uralians, and thus a source of further loanwords shared by all surviving Uralic languages.

Confirming this ‘concentrated’ Uralic expansion to the east is the presence of R1a-M417 (xR1a-Z645) lineages among early and late Single Grave groups in the west – which essentially disappeared after the Bell Beaker expansion – , as well as the presence of these subclades in modern Central and Western Europeans. Central European groups became thus integrated in post-Bell Beaker European EBA cultures, and their Uralic dialect likely disappeared without a trace.

NOTE. The fate of R1b-L51 lineages – linked to North-West Indo-Europeans undergoing a bottleneck in the Yamna Hungary -> Bell Beaker migration to the west – is thus similar to haplogroup R1a-Z645 – linked to the expansion of Late Uralians to the east – , hence proving the traditional interpretation of the language expansions as male-driven migrations. These are two of the most interesting genetic data we have to date to confirm previous language expansions and dialectal classifications.

It will be also interesting to see if known GAC and Corded Ware I2a-Y6098 subclades formed eventually part of the ancient Uralic groups in the east, apart from lineages which will no doubt appear among asbestos ware groups and probably hunter-gatherers from north-eastern Europe (see the recent study by Tambets et al. 2018).

Corded Ware ancestry marked the expansion of Uralians

Sadly, some brilliant minds decided in 2015 that the so-called “Yamnaya ancestry” (now more appropriately called “steppe ancestry”) should be associated to ‘Indo-Europeans’. This is causing the development of various new pet theories on the go, as more and more data contradicts this interpretation.

There is a clear long-lasting cultural, populational, and natural barrier between Yamna and Corded Ware: they are derived from different ancestral populations, which show clearly different ancestry and ancestry evolution (although they did converge to some extent), as well as different Y-DNA bottlenecks; they show different cultures, including those of preceding and succeeding groups, and evolved in different ecological niches. The only true steppe pastoralists who managed to dominate over grasslands extending from the Upper Danube to the Altai were Yamna peoples and their cultural successors.

corded-ware-yamna-pca
Corded Ware admixture proper of expanding late Sredni Stog-like populations from the forest-steppe. See full version here.

NOTE. You can also read two recent posts by FrankN in the blog aDNA era, with detailed information on the Pontic-Caspian cultures and the formation of “steppe ancestry” during the Palaeolithic, Mesolithic and Neolithic: How did CHG get into Steppe_EMBA? Part 1: LGM to Early Holocene and How did CHG get into Steppe_EMBA? Part 2: The Pottery Neolithic. Unlike your typical amateur blogger on genetics using few statistical comparisons coupled with ‘archaeolinguoracial mumbo jumbo’ to reach unscientific conclusions, these are obviously carefully redacted texts which deserve to be read.

I will not enter into the discussion of “steppe ancestry” and the mythical “Siberian ancestry” for this post, though. I will just repost the opinion of Volker Heyd – an archaeologist specialized in Yamna Hungary and Bell Beakers who is working with actual geneticists – on the early conclusions based on “steppe ancestry”:

[A]rchaeologist Volker Heyd at the University of Bristol, UK, disagreed, not with the conclusion that people moved west from the steppe, but with how their genetic signatures were conflated with complex cultural expressions. Corded Ware and Yamnaya burials are more different than they are similar, and there is evidence of cultural exchange, at least, between the Russian steppe and regions west that predate Yamnaya culture, he says. None of these facts negates the conclusions of the genetics papers, but they underscore the insufficiency of the articles in addressing the questions that archaeologists are interested in, he argued. “While I have no doubt they are basically right, it is the complexity of the past that is not reflected,” Heyd wrote, before issuing a call to arms. “Instead of letting geneticists determine the agenda and set the message, we should teach them about complexity in past human actions.

Related

Dzudzuana, Sidelkino, and the Caucasus contribution to the Pontic-Caspian steppe

hunter-gatherer-pottery

It has been known for a long time that the Caucasus must have hosted many (at least partially) isolated populations, probably helped by geographical boundaries, setting it apart from open Eurasian areas.

David Reich writes in his book the following about India:

The genetic data told a clear story. Around a third of Indian groups experienced population bottlenecks as strong or stronger than the ones that occurred among Finns or Ashkenazi Jews. We later confirmed this finding in an even larger dataset that we collected working with Thangaraj: genetic data from more than 250 jati groups spread throughout India (…)

Rather than an invention of colonialism as Dirks suggested, long-term endogamy as embodied in India today in the institution of caste has been overwhelmingly important for millennia. (…)

The Han Chinese are truly a large population. They have been mixing freely for thousands of years. In contrast, there are few if any Indian groups that are demographically very large, and the degree of genetic differentiation among Indian jati groups living side by side in the same village is typically two to three times higher than the genetic differentiation between northern and southern Europeans. The truth is that India is composed of a large number of small populations.

There is little doubt now, based on findings spanning thousands of years, that the Mesolithic and Neolithic Caucasus hosted various very small populations, even if the ancestral components may be reduced to the few known to date (such as ANE, EHG, AME*, ENA, CHG, and other “deep” ancestral components).

NOTE. I will call the ancestral component of Dzudzuana/Anatolian hunter-gatherers Ancient Middle Easterner (AME), to give a clear idea of its likely extension during the Late Upper Palaeolithic, and to avoid using the more simplistic Dzudzuana, unless it is useful to mention these specific local samples.

dzudzuana-pca
Image modified from Lazaridis et al. (2018), including Caucasus, Don-Volga-Ural, and North Pontic Mesolithic-Neolithic populations. “Ancient West Eurasian population structure. (a) Geographical distribution of key ancient West Eurasian populations. (b) Temporal distribution of key ancient West Eurasian populations (approximate date in ky BP). (c) PCA of key ancient West Eurasians, including additional populations (shown with grey shells), in the space of outgroup f4-statistics (Methods).”

Genetic labs have a strong fixation with ancestry. I guess the use of complex statistical methods gives professionals and laymen alike the feeling of dealing with “Science”, as opposed to academic fields where you have to interpret data. I think language reveals a lot about the way people think, and the fact that ancestral components are called ‘lineages’ – while not wrong per se – is a clear symptom of the lack of interest in the true lineages: Y-DNA haplogroups.

Y-DNA bottlenecks

It has become quite clear that male-biased migrations are often the ones which can be confidently followed for actual population movements and ethnolinguistic identification, at least until the Iron Age. The frequently used Palaeolithic clusters offer a clear example of why ancestry does not represent what some people believe: They merely give a basic idea of sizeable population replacements by distant peoples.

Both concepts are important: sizeable and distant peoples. For example, during the Upper Palaeolithic in Europe there was a sizeable population replacement of the Aurignacian Goyet cluster by the Gravettian Vestonice cluster (probably from populations of far eastern Russia) coupled with the arrival of haplogroup I, although during the thousands of years that this material culture lasted, the previously expanded C1a2 lineages did not disappear, and there were probably different resurgence and admixture events.

Haplogroup I certainly expanded with the Gravettian culture to Iberia, where the Goyet ancestry did not change much – probably because of male-driven migrations -, to the extent that during the Magdalenian expansions haplogroup I expanded with an ancestry closer to Goyet, in what is called a ‘resurge’ of the Goyet cluster – even though there is a clear replacement of male lines.

The Villabruna (WHG) cluster is another good example. It probably spread with haplogroup R1b-L754, which – based on the extra ‘East Asian’ affinity of some samples and on modern samples from the Middle East – came probably from the east through a southern route, and not too long before the expansion of WHG likely from around the Black Sea, although this is still unclear. The finding of haplogroup I in samples of mostly WHG ancestry could confuse people that do not care about timing, sub-structured populations, and gene flow.

palaeolithic-expansions-reich
Image from David Reich’s Who We Are and How We Got Here. Having migrated out of Africa and the Near East, modern human pioneer populations spread throughout Eurasia (1). By at least thirty-nine thousand years ago, one group founded a lineage of European hunter-gatherers that persisted largely uninterrupted for more than twenty thousand years (2). Eventually, groups derived from an eastern branch of this founding population of European huntergatherers spread west (3), displaced previous groups, and were eventually themselves pushed out of northern Europe by the spread of glacial ice, shown at its maximum extent (top right). As the glaciers receded, western Europe was repeopled from the southwest (4) by a population that had managed to persist for tens of thousands of years and was related to an approximately thirty-five-thousand-year old individual from far western Europe. A later human migration, following the first strong warming period, had an even larger impact, with a spread from the southeast (5) that not only transformed the population of western Europe but also homogenized the populations of Europe and the Near East. At a single site—Goyet Caves in Belgium—ancient DNA from individuals spread over twenty thousand years reflects these transformations, with representatives from the Aurignacian, Gravettian, and Magdalenian periods.

NOTE. If you don’t understand why ‘clusters’ that span thousands of years don’t really matter for the many Palaeolithic population expansions that certainly happened among hunter-gatherers in Europe, just take a look at what happened with Bell Beakers expanding from Yamna into western Europe within 500 years.

If we don’t thread carefully when talking about population migrations, these terms are bound to confuse people. Just as the fixation on “steppe ancestry” – which marks the arrival in Chalcolithic Europe of peoples from the Pontic-Caspian region – has confused a lot of researchers to this day.

When I began to write about the Indo-European demic diffusion model, my concern was to find a single spot where a North-West Indo-European proto-language could have expanded from ca. 2000 BC (our most common guesstimate). Based on the 2015 papers, and in spite of their conclusions, I thought it had become clear that Corded Ware was not it, and it was rather Bell Beakers. I assumed that Uralic was spoken to the north (as was the traditional belief), and thus Corded Ware expanded from the forest zone, hence steppe ancestry would also be found there with other R1a lineages.

With the publication of Mathieson et al. (2017) and Olalde et al. (2017), I changed my mind, seeing how “steppe ancestry” did in fact appear quite late, hence it was likely to be the result of very specific population movements, probably directly from the Caucasus. Later, Mathieson published in a revision the sample from Alexandria of hg R1a-M417 (probably R1a-Z645, possibly Z93+), which further supported the idea that the migration of Corded Ware peoples started near the North Pontic forest-steppe (as I included in a the next revision).

The question remains the same I repeated recently, though: where do the extra Caucasus components (i.e. beyond EHG) of Eneolithic Ukraine/Corded Ware and Khvalynsk/Yamna come from?

Steppe ancestry: “EHG” + “CHG”?

About EHG ancestry

From Lazaridis et al. (2018):

Considering 2-way mixtures, we can model Karelia_HG as deriving 34 ± 2.8% of its ancestry from a Villabruna-related source, with the remainder mainly from ANE represented by the AfontovaGora3 (AG3) sample from Lake Baikal ~17kya.

AG3 was likely of haplogroup Q1a (as reported by YFull, see Genetiker), and probably the ANE ancestry found in Eastern Europe accompanied a Palaeolithic migration of Q1a2-M25 (formed ca. 22600 BC, TMRCA ca. 14300 BC).

NOTE. You can read more about the expansion of Q lineages during the Palaeolithic.

Combined with what we know about the Eneolithic Steppe and Caucasus populations – it is likely that ANE ancestry remained the most important component of some of the small ghost populations of the Caucasus until their emergence with the Lola culture.

pca-caucasus-dzudzuana
Image modified from Wang et al. (2018). Samples projected in PCA of 84 modern-day West Eurasian populations (open symbols). Previously known clusters have been marked and referenced. Marked and labelled are the Balkan samples referenced in this text An EHG and a Caucasus ‘clouds’ have been drawn, leaving Pontic-Caspian steppe and derived groups between them. See the original file here. To understand the drawn potential Caucasus Mesolithic cluster, see above the PCA from Lazaridis et al. (2018).

The first sample we have now attributed to the EHG cluster is Sidelkino, from the Samara region (ca. 9300 BC), mtDNA U5a2. In Damgaard et al. (Science 2018), Yamnaya could be modelled as a CHG population related to Kotias Klde (54%) and the remaining from ANE population related to Sidelkino (>46%), with the following split events:

  1. A split event, where the CHG component of Yamnaya splits from KK1. The model inferred this time at 27 kya (though we note the larger models in Sections S2.12.4 and S2.12.5 inferred a more recent split time).
  2. A split event, where the ANE component of Yamnaya splits from Sidelkino. This was inferred at about about 11 kya.
  3. A split event, where the ANE component of Yamnaya splits from Botai. We inferred this to occur 17 kya. Note that this is above the Sidelkino split time, so our model infers Yamnaya to be more closely related to the EHG Sidelkino, as expected.
  4. An ancestral split event between the CHG and ANE ancestral populations. This was inferred to occur around 40 kya.

Other samples classified as of the EHG cluster:

  • Popovo2 (ca. 6250 BC) of hg J1, mtDNA U4d – Po2 and Po4 from the same site (ca. 6550 BC) show continuity of mtDNA.
  • Karelia_HG, from Juzhnii Oleni Ostrov (ca. 6300 BC): I0211/UzOO40 (ca. 6300 BC) of hg J1(xJ1a), mtDNA U4a; and I0061/UzOO74 of hg R1a1(xR1a1a), mtDNA C1
  • UzOO77 and UzOO76 from Juzhnii Oleni Ostrov (ca. 5250 BC) of mtDNA R1b.
  • Samara_HG from Lebyanzhinka (ca. 5600 BC) of hg R1b1a, mtDNA U5a1d.

From the analysis of Lazaridis et al. (2018), we have some details about their admixture:

dzudzuana-admixture-sidelkino
Image modified from Lazaridis et al. (2018). Modeling present-day and ancient West-Eurasians. Mixture proportions computed with qpAdm (Supplementary Information section 4). The proportion of ‘Mbuti’ ancestry represents the total of ‘Deep’ ancestry from lineages that split prior to the split of Ust’Ishim, Tianyuan, and West Eurasians and can include both ‘Basal Eurasian’ and other (e.g., Sub-Saharan African) ancestry. (Left) ‘Conservative’ estimates. Each population 367 cannot be modeled with fewer admixture events than shown. (Right) ‘Speculative’ estimates. The highest number of sources (≤5) with admixture estimates within [0,1] are shown for each population. Some of the admixture proportions are not significantly different from 0 (Supplementary Information section 4).

About Anatolia_Neolithic ancestry

About the enigmatic Anatolia_Neolithic-related ancestry found in Pontic-Caspian steppe samples, this is what Wang et al. (2018) had to say:

We focused on model of mixture of proximal sources such as CHG and Anatolian Chalcolithic for all six groups of the Caucasus cluster (Eneolithic Caucasus, Maykop and Late Makyop, Maykop-Novosvobodnaya, Kura-Araxes, and Dolmen LBA), with admixture proportions on a genetic cline of 40-72% Anatolian Chalcolithic related and 28-60% CHG related (Supplementary Table 7). When we explored Romania_EN and Greece_Neolithic individuals as alternative southeast European sources (30-46% and 36-49%), the CHG proportions increased to 54-70% and 51-64%, respectively. We hypothesize that alternative models, replacing the Anatolian Chalcolithic individual with yet unsampled populations from eastern Anatolia, South Caucasus or northern Mesopotamia, would probably also provide a fit to the data from some of the tested Caucasus groups.

Also:

The first appearance of ‘Near Eastern farmer related ancestry’ in the steppe zone is evident in Steppe Maykop outliers. However, PCA results also suggest that Yamnaya and later groups of the West Eurasian steppe carry some farmer related ancestry as they are slightly shifted towards ‘European Neolithic groups’ in PC2 (Fig. 2D) compared to Eneolithic steppe. This is not the case for the preceding Eneolithic steppe individuals. The tilting cline is also confirmed by admixture f3-statistics, which provide statistically negative values for AG3 as one source and any Anatolian Neolithic related group as a second source

yamnaya-caucasus-dzudzuana
Modified image from Wang et al. (2018). In blue, Yamna-related populations. In red, Corded Ware-related populations, and two elevated Anatolia_Neolithic values in Yamna. Notice how only GAC-related admixture increases the Anatolian_N-related ancestry in the Yamna outlier from Ozero, and the late Yamna sample from Hungary, related to the homogeneous Yamna population. “Supplementary Table 14. P values of rank=3 and admixture proportions in modelling Steppe ancestry populations as a four-way admixture of distal sources EHG, CHG, Anatolian_Neolithic and WHG using 14 outgroups.Left populations: Steppe cluster, EHG, CHG, WHG, Anatolian_Neolithic. Right populations: Mbuti.DG, Ust_Ishim.DG, Kostenki14, MA1, Han.DG, Papuan.DG, Onge.DG, Villabruna, Vestonice16, ElMiron, Ethiopia_4500BP.SG, Karitiana.DG, Natufian, Iran_Ganj_Dareh_Neolithic.”

Detailed exploration via D-statistics in the form of D(EHG, steppe group; X, Mbuti) and D(Samara_Eneolithic, steppe group; X, Mbuti) show significantly negative D values for most of the steppe groups when X is a member of the Caucasus cluster or one of the Levant/Anatolia farmer-related groups (Supplementary Figs. 5 and 6). In addition, we used f- and D-statistics to explore the shared ancestry with Anatolian Neolithic as well as the reciprocal relationship between Anatolian- and Iranian farmer-related ancestry for all groups of our two main clusters and relevant adjacent regions (Supplementary Fig. 4). Here, we observe an increase in farmer-related ancestry (both Anatolian and Iranian) in our Steppe cluster, ranging from Eneolithic steppe to later groups. In Middle/Late Bronze Age groups especially to the north and east we observe a further increase of Anatolian farmer related ancestry consistent with previous studies of the Poltavka, Andronovo, Srubnaya and Sintashta groups and reflecting a different process not especially related to events in the Caucasus.

(…) Surprisingly, we found that a minimum of four streams of ancestry is needed to explain all eleven steppe ancestry groups tested, including previously published ones (Fig. 2; Supplementary Table 12). Importantly, our results show a subtle contribution of both Anatolian farmer-related ancestry and WHG-related ancestry (Fig.4; Supplementary Tables 13 and 14), which was likely contributed through Middle and Late Neolithic farming groups from adjacent regions in the West. The discovery of a quite old AME ancestry has rendered this probably unnecessary, because this admixture from an Anatolian-like ghost population could be driven even by small populations from the Caucasus.

yamna-caucasus-cwc-anatolia-neolithic
Image modified from Wang et al. (2018). Marked are: in red, approximate limit of Anatolia_Neolithic ancestry found in Yamna populations; in blue, Corded Ware-related groups. “Modelling results for the Steppe and Caucasus 1128 cluster. Admixture proportions based on (temporally and geographically) distal and proximal models, showing additional Anatolian farmer-related ancestry in Steppe groups as well as additional gene flow from the south in some of the Steppe groups as well as the Caucasus groups (see also Supplementary Tables 10, 14 and 20).”

NOTE. For a detailed account of the possibilities regarding this differential admixture in the North Pontic area in contrast to the Don-Volga-Ural region, you can read the posts Sredni Stog, Proto-Corded Ware, and their “steppe admixture”, and Corded Ware culture origins: The Final Frontier.

While it is not yet fully clear, the increased Anatolian_Neolithic-like ancestry in Ukraine_Eneolithic samples (see below) makes it unlikely that all such ancestry in Corded Ware groups comes from a GAC-related contribution. It is likely that at least part of it represents contributions from populations of the Caucasus, based on the mostly westward population movements in the steppe from ca. 4600 BC on, including the Suvorovo-Novodanilovka expansion, and especially the Kuban-Maykop expansion during the final Eneolithic into the North Pontic area.

NOTE. Since CHG-like groups from the Caucasus may have combinations of AME and ANE ancestry similar to Yamna (which may thus appear as ‘steppe ancestry’ in the North Pontic area), it is impossible to interpret with precision the following ADMIXTURE graphic:

ukraine-whg-ehg-steppe
Modified image from Mathieson et al. (2018). Supervised ADMIXTURE analysis, modelling each ancient individual (one per row) as a mixture of population clusters constrained to contain northwestern-Anatolian Neolithic (grey), Yamnaya from Samara (yellow), EHG (pink) and WHG (green) populations. Dates in parentheses indicate approximate range of individuals in each population.

North-Eastern Technocomplex

The East Asian contribution to samples from the WHG samples (like Loschbour or La Braña), as specified in Fu et al. (2016), does not seem to be related to Baikal_EN, and appears possibly (in the ADMIXTURE analysis) integrated into he Villabruna component. I guess this implies that the shared alleles with East Asians are quite early, and potentially due to the expansion of R1b-L754 from the East.

It would be interesting to know the specific material culture Sidelkino belonged to – i.e. if it was related to the expansion of the North-Eastern Technocomplex – , and its Y-DNA. The Post-Swiderian expansion into eastern Europe, probably associated with the expansion of R1b-P297 lineages (including R1b-M73, found later in Botai and in Baltic HG) is supposed to have begun during the 11th millennium BC, but migrations to the Urals and beyond are probably concentrated in the 9th millennium, so this sample is possibly slightly early for R1b.

NOTE. User Rozenfeld at Anthrogenica posted this, which I think is interesting (in case anyone wants to try a Y-SNP call):

there is something strange with Sidelkino EHG: first, its archaeological context is not described in the supplementary. Second, its sex is not listed in the supplementary tables. Third, after looking for info about this sample, I found that: “Сиделькино-3. Для снятия вопроса о половой принадлежности индивида была проведена генетическая экспертиза, выявившая принадлежность останков мужчине.”(translation: Sidelkino-3. To resolve the question about sex of the remains, the genetic analysis was conducted, which showed that remains belonged to male), source: http://static.iea.ras.ru/books/7487_Traditsii.pdf

So either they haven’t mentioned his Y-DNA in the paper for some reason, or there are more than one Sidelkino sample and the male one has not yet been published. The coverage of the Sidelkino sample from the paper is 2.9, more than enough to tell Y-DNA haplogroup.

zaliznyak-post-swiderian
The map of spreading of Post-Swiderian and Post-Krasnosillian sites in Mesolithic of Eastern Europe in the 8th millennia BC. From Zaliznyak (see here).

My speculative guess right now about specific population movements in far eastern Europe, based on the few data we have:

  • The expansion of the North-Eastern Technocomplex first around the 9th millennium BC, most likely expanded R1b-P279 ca. 11300 BC, judging by its TMRCA, with both R1b-M73 (TMRCA 5300) and R1b-M269 (TMRCA 4400 BC) info (with extra El Mirón ancestry) back, and thus Eurasiatic.
  • The expansion of haplogroup J1 to the north may have happened before or after the R1b-P279 expansion. Judging by the increase in AG3-related ancestry near Karelia compared to Baltic_HG, it is possible that it expanded just after R1b-P279 (hence possibly J1-Y6304? TMRCA 9700 BC). Its long-lasting presence in the Caucasus is supported by the Satsurblia (ca. 11300 BC) and the Dolmen BA (ca. 1300 BC) samples.
  • The expansion of R1a-M17 ca. 6600 BC is still likely to have happened from the east, based on the R1a-M17 samples found in Baikalic cultures slightly later (ca. 5300 BC). The presence of elevated Baikal_EN ancestry in Karelia HG and in Samara HG, and the finding of R1a-M417 samples in the Forest Zone after the Mesolithic suggests a connection with the expansion of Hunter-Gatherer pottery, from the Elshanka culture in the Samara region northward into the Forset Zone and westward into the North Pontic area.
  • The expansion of R1b-M73 ca. 5300 BC is likely to be associated with the emergence of a group east of the Urals (related to the later Botai culture, and potentially Pre-Yukaghir). Its presence in a Narva sample from Donkalnis (ca. 5200 BC) suggest either an early split and spread of both R1b-P297 lineages (M73 and M269) through Eastern Europe, or maybe a back-migration with hunter-gatherer pottery.
  • R1b-M269 spread successfully ca. 4400 BC (and R1b-L23 ca. 4100 BC, both based on TMRCA), and this successful expansion is probably to be associated with the Khvalynsk-Novodanilovka expansion. We already know that Samara_HG ca. 5600 was R1b1a, so it is likely that R1b-M269 appeared (or ‘resurged’) in the Volga-Ural region shortly after the expansion of R1a-M17, whose expansion through the region may be inferred by the additional AG3 and Baikal_EN ancestry. Interesting from Samara_HG compared to the previous Sidelkino sample is the introduction of more El Mirón-related ancestry, typical of WHG populations (and thus proper of Baltic groups).

NOTE. The TMRCA dates are obviously gross approximations, because a) the actual rate of mutation is unknown and b) TMRCA estimates are based on the convergence of lineages that survived. The potential finding of R1a-Z645 (possibly Z93+) in Ukraine Eneolithic (ca. 4000 BC), and the potential finding of R1b-L23 in Khvalynsk ca. 4250 BC complicates things further, in terms of dates and origins of any subclade.

The question thus remains as it was long ago: did R1b-M269 lineages expand (‘return’) from the east, near the Urals, or directly from the north? Were they already near Samara at the same time as the expansion of hunter-gatherer pottery, and were not much affected by it? Or did they ‘resurge’ from populations admixed with Caucasus-related ancestry after the expansion of R1a-M17 with this pottery (since there are different stepped expansions from the Samara region)? We could even ask, did R1a-M17 really expand from the east, i.e. are the dates on Baikalic subclades from Moussa et al. (2016) reliable? Or did R1a-M17 expand from some pockets in the Pontic-Caspian steppe, taking over the expansion of HG pottery at some point?

hunger-gatherer-pottery
Early Neolithic cultures in eastern and central Europe: 1–Yelshanian; 2–North Caspian; 3–Rakushechnyj Yar; 4–Surskian; 5–Dnieper-Donetsian; 6– Bug-Dniesterian; 7–Upper Volga; 8–Narvian; 9–Linear Pottery. White arrows: expansion of early farming; black arrows: spread of pottery-making traditions. From Dolukhanov et al. (2009).

Maglemose-related migrations

The most interesting aspect from the new paper (regarding Indo-Uralic migrations) is that Ancestral Middle Easterner ancestry will probably be a better proxy for the Anatolia_Neolithic component found in Ukraine Mesolithic to Eneolithic, and possibly also for some of the “more CHG-like” component found among Pontic-Caspian steppe populations, all likely derived from different admixture events with groups from the Caucasus.

NOTE. Even the supposed gene flow of Neolithic Iranian ancestry into the Caucasus can be put into question, since that means possibly a Dzudzuana-like population with greater “deep ancestry” proportion than the one found in CHG, which may still be found within the Caucasus.

If it was not clear already that following ‘steppe ancestry’ wherever it appears is a rather lame way of following Indo-European migrations, every single sample from the Caucasus and their admixture with Pontic-Caspian steppe populations will probably show that “steppe ancestry” is in fact formed by a variety of steppe-related ancestral components, impossible to follow coherently with a single population. Exactly what is happening already with the Siberian ancestry.

If the paper on the Dzudzuana samples has shown something, is that the expansion of an ANE-like population shook the entire Caucasus area up to the Zagros Mountains, creating this ANE – AME cline that are CHG and Iran_N, with further contributions of “deep ancestries” (probably from the south) complicating the picture further.

If this happens with few known samples, and we know of an ANE-like ghost population in the Caucasus (appearing later in the Lola culture), we can already guess that the often repeated “CHG component” found in Ukraine_Eneolithic and Khvalynsk will not be the same (except the part mediated by the Novodanilovka expansion).

This ANE-like expansion happened probably in the Late Upper Palaeolithic, and reached Northern Europe probably after the expansion of the Villabruna cluster (ca. 12000 BC), judging by the advance of AG3-like and ENA-like ancestry in later WHG samples.

The population movements during the Mesolithic and Early Neolithic in the North Pontic area are quite complicated: the extra AME ancestry is probably connected to the admixture with populations from the Caucasus, while the close similarity of Ukraine populations with Scandinavian ones (with an increase in Villabruna ancestry from Mesolithic to Neolithic samples), probably reveal population movements related to the expansion of Maglemose-related groups.

maglemose-mesolithic
Etno-cultural situation in Central and Eastern Europe in the Late Mesolithic — Early Neolithic (VI—V Mill. BC) (after Конча 2004: 201, карта 1; made after ideas by L. L. Zaliznyak). Legend: 1 — Maglemose circle in the VII Mill. BC (after Gr. Clark); 2—7 — Mesolithic cultures of the Post-Maglemose tradition, VI Mill. BC (after S. Kozłowsky, L. L. Zaliznyak): 2 — de Leyen-Wartena; 3 — Oldesloe — Godenaa; 4 — Chojnice — Peńki; 5 — Janisłavice; 6 — finds of Janisłavice artefacts outside of the main area; 7 — Donets culture; 8 — directions of the settling of Janisłavice people (after S. Kozłowsky and L. L. Zaliznyak); 9 — the south border of Mesolithic and Early Neolithic cultures of post-Swidrian and post-Arensburgian traditions; 10 — northern border of settlement of the Balkan-Danubian farmers; 11 — Bug- Dniester culture; 12 — Neolithic cultures emerged on the ethno-cultural basis of post-Maglemose: Э — Ertebölle-Ellerbeck, Н — Neman, Д — Dnieper-Donets, М — Mariupol (western variants). From Klein (2017).

These Maglemose-related groups were probably migrants from the north-west, originally from the Northern European Plains, who occupied the previous Swiderian territory, and then expanded into the North Pontic area. The overwhelming presence of I2a (likely all I2a2a1b1b) lineages in Ukraine Neolithic supports this migration.

The likely picture of Mesolithic-Neolithic migrations in the North Pontic area right now is then:

  1. Expansion of R1a-M459 from the east ca. 12000 BC – probably coupled with AG3 and also some Baikal_EN ancestry. First sample is I1819 from Vasilievka (ca. 8700 BC), another is from Dereivka ca. 6900 BC.
  2. Expansion of R1b-V88 from the Balkans in the west ca. 9700 BC, based on its TMRCA and also the Balkan hunter-gatherer population overwhemingly of this haplogroup from the 10th millennium until the Neolithic. First sample is I1734 from Vasilievka (ca. 7252 BC), which suggests that it replaced the male population there, based on their similar EHG-like adxmixture (and lack of sizeable WHG increase), and shared mtDNA U5b2, U5a2.
  3. Expansion of I2a-Y5606 probably ca. 6800 based on its TMRCA with Janislawice culture. Supporting this is the increase in WHG contribution to Neolithic samples, including the spread of U4 subclades compared to the previous period.
  4. Expansion of R1a-M17 starting probably ca. 6600 BC in the east (see above).

NOTE. The first sample of haplogroup I appears in the Mesolithic: I1763 (ca. 8100 BC) of haplogroup I2a1, probably related to an older Upper Palaeolithic expansion.

janislawice
Distribution of archeological cultures in the North Pontic Region during the Mesolithic (7th – 6th millennium BCE). Dotted, dashed and solid lines with corresponding arrows indicate alternative models of the spread of the Grebenyky culture groups. (After Bryuako IV., Samojlova TL., Eds, Drevnie kul’tury Severo-­‐Zapadnogo Prichernomor’ya, Odessa: SMIL, 2013.) Nikitin – Ivanova 2017.

Conclusion

It is becoming more and more clear with each new paper that – unless the number of very ancient samples increases – the use of Y-chromosome haplogroups remains one of the most important tools for academics; this is especially so in the steppes, in light of the diversity found in populations from the Caucasus. A clear example comes from the Yamna – Corded Ware similarities:

After the publication of the 2015 papers, it was likely that Yamna expanded with haplogroup R1b-L23, but it has only become crystal clear that Yamna expanded through the steppes into Bell Beakers, now that we have data about the strict genetic homogeneity of the whole Yamna population from west to east (including Afanasevo), in contrast with contemporary Corded Ware peoples which expanded from a different forest-steppe population.

The presence of haplogroups Q and R1a-M459 (xM17) in Khvalynsk along with a R1b1a sample, which some interpreted as being akin to modern ‘mixed’ populations in the past, is likely to point instead to a period of Khvalynsk-Novodanilovka expansion with R1b-M269, where different small populations from the steppe were being integrated into the common Khvalynsk stock, but where differences are seen in material culture surrounding their burials, as supported by the finding of R1b1 in the Kuban area already in the first half of the 5th millennium. The case would be similar to the early ‘mixed’ Icelandic population.

Only after the emergence of the Samara culture (in the second half of the 6th millennium BC), with a sample of haplogroup R1b1a, starts then the obvious connection with Early Proto-Indo-Europeans; and only after the appearance of late Sredni Stog and haplogroup R1a-M417 (ca. 4000 BC) is its connection with Uralic also clear. In previous population movements, I think more haplogroups were involved in migrations of small groups, and only some communities among them were eventually successful, expanding to be dominant, creating ever growing cultures during their expansions.

Indeed, if you think in terms of Uralic and Indo-European just as converging languages, and forget their potential genetic connection, then the genetic + linguistic picture becomes simplified, and the upper frontier of the 6th millennium BC with a division North Pontic (Mariupol) vs. Volga-Ural (Samara) is enough. However, tracing their movements backwards – with cultural expansions from west to east (with the expansion of farming), and earlier east to west (with hunter-gatherer pottery), and still earlier west to east (with the north-eastern technocomplex), offers an interesting way to prove their potential connection to macrofamilies, at least in terms of population movements.

corded-ware-uralic-qpgraph
Modified image from Tambets et al. (2018) Proportions of ancestral components in studied European and Siberian populations and the tested qpGraph model. a The qpGraph model fitting the data for the tested populations. Colour codes for the terminal nodes: pink—modern populations (‘Population X’ refers to test population) and yellow—ancient populations (aDNA samples and their pools). Nodes coloured other than pink or yellow are hypothetical intermediate populations. We putatively named nodes which we used as admixture sources using the main recipient among known populations. The colours of intermediate nodes on the qpGraph model match those on the admixture proportions panel. The NeolL (Neolithic Levant) ancestry selected in this qpGraph is likely to correspond (at least in part) to a specific Dzudzuana-like component present in the CHG-like population that admixed in the North Pontic area.

I am quite convinced right now that it would be possible to connect the expansion of R1b-L754 subclades with a speculative Nostratic (given the R1b-V88 connection with Afroasiatic, and the obvious connection of R1b-L297 with Eurasiatic). Paradoxically, the connection of an Indo-Uralic community in the steppes (after the separation of Yukaghir) with any lineage expansion (R1a-M17, R1b-M269, or even Q, I or J1) seems somehow blurrier than one year ago, possibly just because there are too many open possibilities.

David Reich says about the admixture with Neanderthals, which he helped discover:

At the conclusion of the Neanderthal genome project, I am still amazed by the surprises we encountered. Having found the first evidence of interbreeding between Neanderthals and modern humans, I continue to have nightmares that the finding is some kind of mistake. But the data are sternly consistent: the evidence for Neanderthal interbreeding turns out to be everywhere. As we continue to do genetic work, we keep encountering more and more patterns that reflect the extraordinary impact this interbreeding has had on the genomes of people living today.

I think this is a shared feeling among many of us who have made proposals about anything, to fear that we have made a gross, evident mistake, and constantly look for flaws. However, it seems to me that geneticists are more preoccupied with being wrong in their developed statistical methods, in the theoretical models they are creating, and not so much about errors in the true ancient ethnolinguistic picture human population genetics is (at least in theory) concerned about. Their publications are, after all, constantly associating genetic finds with cultures and (whenever possible) languages, so this aspect of their research should not be taken lightly.

Seeing how David Anthony or Razib Khan (among many others) have changed their previously preferred migration models as new data was published, and they continue to be respected in their own fields, I guess we can be confident that professionals with integrity are going to accept whatever new picture appears. While I don’t think that genetic finds can change what we can reconstruct with comparative grammar, I am also ready to revise guesstimates and routes of expansion of certain dialects if R1a-Z645 is shown to have accompanied Late Proto-Indo-Europeans during their expansion with Yamna, and later integrated somehow with Corded Ware.

However, taking into account the obsession of some with an ancestral, uninterrupted R1a—Indo-European association, and the lack of actual political repercussion of Neanderthal admixture, I think the most common nightmare that all genetic researchers should be worried about is to keep inflating this “Yamnaya ancestry”-based hornet’s nest, which has been constantly stirred up for the past two years, by rejecting it – or, rather, specifying it into its true complex nature.

This succession of corrections and redefinitions, coupled with the distinct Y-DNA bottleneck of each steppe population, will eventually lead to a completely different ethnolinguistic picture of the Pontic-Caspian region during the Eneolithic, which is likely to eventually piss off not only reasonable academics stubbornly attached to the CWC-IE idea, but also a part of those interested in daydreaming about their patrilineal ancestors.

Sometimes it’s better to just rip off the band-aid once and for all…

Featured image from The oldest pottery in hunter-gatherer communitiesand models of Neolithisation of Eastern Europe (2015), by Andrey Mazurkevich and Ekaterina Dolbunova.

Related

Interesting is today’s post in Ancient DNA Era: Is Male-driven Genetic Replacement always meaning Language-shift?

Early Iranian steppe nomadic pastoralists also show Y-DNA bottlenecks and R1b-L23

New paper (behind paywall) Ancient genomes suggest the eastern Pontic-Caspian steppe as the source of western Iron Age nomads, by Krzewińska et al. Science (2018) 4(10):eaat4457.

Interesting excerpts (emphasis mine, some links to images and tables deleted for clarity):

Late Bronze Age (LBA) Srubnaya-Alakulskaya individuals carried mtDNA haplogroups associated with Europeans or West Eurasians (17) including H, J1, K1, T2, U2, U4, and U5 (table S3). In contrast, the Iron Age nomads (Cimmerians, Scythians, and Sarmatians) additionally carried mtDNA haplogroups associated with Central Asia and the Far East (A, C, D, and M). The absence of East Asian mitochondrial lineages in the more eastern and older Srubnaya-Alakulskaya population suggests that the appearance of East Asian haplogroups in the steppe populations might be associated with the Iron Age nomads, starting with the Cimmerians.

scythian-cimmerian-sarmatian-y-dna-mtdna

#UPDATE (5 OCT 2018): Some Y-SNP calls have been published in a Molgen thread, with:

  • Srubna samples have possibly two R1a-Z280, three R1a-Z93.
  • Cimmerians may not have R1b: cim357 is reported as R1a.
  • Some Scythians have low coverage to the point where it is difficult to assign even a reliable haplogroup (they report hg I2 for scy301, or E for scy197, probably based on some shared SNPs?), but those which can be reliably assigned seem R1b-Z2103 [hence probably the use of question marks and asterisks in the table, and the assumption of the paper that all Scythians are R1b-L23]:
    • The most recent subclade is found in scy305: R1b-Z2103>Z2106 (Z2106+, Y12538/Z8131+)
    • scy304: R1b-Z2103 (M12149/Y4371/Z8128+).
    • scy009: R1b-P312>U152>L2 (P312+, U152?, L2+)?
  • Sarmatians are apparently all R1a-Z93 (including tem002 and tem003);
  • You can read here the Excel file with (some probably as speculative as the paper’s own) results.

    About the PCA

    1. Srubnaya-Alakulskaya individuals exhibited genetic affinity to northern and northeastern present-day Europeans, and these results were also consistent with outgroup f3 statistics.
    2. The Cimmerian individuals, representing the time period of transition from Bronze to Iron Age, were not homogeneous regarding their genetic similarities to present-day populations according to the PCA. F3 statistics confirmed the heterogeneity of these individuals in comparison with present-day populations
    3. The Scythians reported in this study, from the core Scythian territory in the North Pontic steppe, showed high intragroup diversity. In the PCA, they are positioned as four visually distinct groups compared to the gradient of present-day populations:
      1. A group of three individuals (scy009, scy010, and scy303) showed genetic affinity to north European populations (…).
      2. A group of four individuals (scy192, scy197, scy300, and scy305) showed genetic similarities to southern European populations (…).
      3. A group of three individuals (scy006, scy011, and scy193) located between the genetic variation of Mordovians and populations of the North Caucasus (…). In addition, one Srubnaya-Alakulskaya individual (kzb004), the most recent Cimmerian (cim357), and all Sarmatians fell within this cluster. In contrast to the Scythians, and despite being from opposite ends of the Pontic-Caspian steppe, the five Sarmatians grouped close together in this cluster.
      4. A group of three Scythians (scy301, scy304, and scy311) formed a discrete group between the SC and SE and had genetic affinities to present-day Bulgarian, Greek, Croatian, and Turkish populations (…).
      5. Finally, one individual from a Scythian cultural context (scy332) is positioned outside of the modern West Eurasian genetic variation (Fig. 1C) but shared genetic drift with East Asian populations.
    scythian-cimmerian-pca
    Radiocarbon ages and geographical locations of the ancient samples used in this study. Figure panels presented (Left) Bar plot visualizing approximate timeline of presented and previously published individuals. (Right) Principal component analysis (PCA) plot visualizing 35 Bronze Age and Iron Age individuals presented in this study and in published ancient individuals (table S5) in relation to modern reference panel from the Human Origins data set (41).

    Cimmerians

    The presence of an SA component (as well as finding of metals imported from Tien Shan Mountains in Muradym 8) could therefore reflect a connection to the complex networks of the nomadic transmigration patterns characteristic of seasonal steppe population movements. These movements, although dictated by the needs of the nomads and their animals, shaped the economic and social networks linking the outskirts of the steppe and facilitated the flow of goods between settled, semi-nomadic, and nomadic peoples. In contrast, all Cimmerians carried the Siberian genetic component. Both the PCA and f4 statistics supported their closer affinities to the Bronze Age western Siberian populations (including Karasuk) than to Srubnaya. It is noteworthy that the oldest of the Cimmerians studied here (cim357) carried almost equal proportions of Asian and West Eurasian components, resembling the Pazyryks, Aldy-Bel, and Iron Age individuals from Russia and Kazakhstan (12). The second oldest Cimmerian (cim358) was also the only one with both uniparental markers pointing toward East Asia. The Q1* Y chromosome sublineage of Q-M242 is widespread among Asians and Native Americans and is thought to have originated in the Altai Mountains (24)

    Scythians

    In contrast to the eastern steppe Scythians (Pazyryks and Aldy-Bel) that were closely related to Yamnaya, the western North Pontic Scythians were instead more closely related to individuals from Afanasievo and Andronovo groups. Some of the Scythians of the western Pontic-Caspian steppe lacked the SA and the East Eurasian components altogether and instead were more similar to a Montenegro Iron Age individual (3), possibly indicating assimilation of the earlier local groups by the Scythians.

    Toward the end of the Scythian period (fourth century CE), a possible direct influx from the southern Ural steppe zone took place, as indicated by scy332. However, it is possible that this individual might have originated in a different nomadic group despite being found in a Scythian cultural context.

    scythian-alakul-variation
    Genetic diversity and ancestral components of Srubnaya-Alakulskaya population.(here called “Srubnaya”): (Left) Mean f3 statistics for Srubnaya and other Bronze Age populations. Srubnaya group was color-coded the same as with PCA. (Right) Pairwise mismatch estimates for Bronze Age populations.

    Comments

    I am surprised to find this new R1b-L23-based bottleneck in Eastern Iranian expansions so late, but admittedly – based on data from later times in the Pontic-Caspian steppe near the Caucasus – it was always a possibility. The fact that pockets of R1b-L23 lineages remained somehow ‘hidden’ in early Indo-Iranian communities was clear already since Narasimhan et al. (2018), as I predicted could happen, and is compatible with the limited archaeological data on Sintashta-Potapovka populations outside fortified settlements. I already said that Corded Ware was out of Indo-European migrations then, this further supports it.

    Even with all these data coming just from a north-west Pontic steppe region (west of the Dnieper), these ‘Cimmerians’ – or rather the ‘Proto-Scythian’ nomadic cultures appearing before ca. 800 BC in the Pontic-Caspian steppes – are shown to be probably formed by diverse peoples from Central Asia who brought about the first waves of Siberian ancestry (and Asian lineages) seen in the western steppes. You can read about a Cimmerian-related culture, Anonino, key for the evolution of Finno-Permic peoples.

    Also interesting about the Y-DNA bottleneck seen here is the rejection of the supposed continuous western expansions of R1a-Z645 subclades with steppe tribes since the Bronze Age, and thus a clearest link of the Hungarian Árpád dynasty (of R1a-Z2123 lineage) to either the early Srubna-related expansions or – much more likely – to the actual expansions of Hungarian tribes near the Urals in historic times.

    NOTE. I will add the information of this paper to the upcoming post on Ugric and Samoyedic expansions, and the late introduction of Siberian ancestry to these peoples.

    A few interesting lessons to be learned:

    • Remember the fantasy story about that supposed steppe nomadic pastoralist society sharing different Y-DNA lineages? You know, that Yamna culture expanding with R1b from Khvalynsk-Repin into the whole Pontic-Caspian steppes and beyond, developing R1b-dominated Afanasevo, Bell Beaker, and Poltavka, but suddenly appearing (in the middle of those expansions through the steppes) as a different culture, Corded Ware, to the north (in the east-central European forest zone) and dominated by R1a? Well, it hasn’t happened with any other steppe migration, so…maybe Proto-Indo-Europeans were that kind of especially friendly language-teaching neighbours?
    • Remember that ‘pure-R1a’ Indo-Slavonic society emerged from Sintashta ca. 2100 BC? (or even Graeco-Aryan??) Hmmmm… Another good fantasy story that didn’t happen; just like a central-east European Bronze Age Balto-Slavic R1a continuity didn’t happen, either. So, given that cultures from around Estonia are those showing the closest thing to R1a continuity in Europe until the Iron Age, I assume we have to get ready for the Gulf of Finland Balto-Slavic soon.
    • Remember that ‘pure-R1a’ expansion of Indo-Europeans based on the Tarim Basin samples? This paper means ipso facto an end to the Tarim Basin – Tocharian artificial controversy. The Pre-Tocharian expansion is represented by Afanasevo, and whether or not (Andronovo-related) groups of R1a-Z645 lineages replaced part or eventually all of its population before, during, or after the Tocharian expansion into the Tarim Basin, this does not change the origin of the language split and expansion from Yamna to Central Asia; just like this paper does not change the fact that these steppe groups were Proto-Iranian (Srubna) and Eastern Iranian (Scythian) speakers, regardless of their dominant haplogroup.
    • And, best of all, remember the Copenhagen group’s recent R1a-based “Indo-Germanic” dialect revival vs. the R1b-Tocharo-Italo-Celtic? Yep, they made that proposal, in 2018, based on the obvious Yamna—R1b-L23 association, and the desire to support Kristiansen’s model of Corded Ware – Indo-European expansion. Pepperidge Farm remembers. This new data on Early Iranians means another big NO to that imaginary R1a-based PIE society. But good try to go back to Gimbutas’ times, though.
    olander-classificatoin
    Olander’s (2018) tree of Indo-European languages. Presented at Languages and migrations in pre-historic Europe (7-12 Aug 2018)

    Do you smell that fresher air? It’s the Central and East European post-Communist populist and ethnonationalist bullshit (viz. pure blond R1a-based Pan-Nordicism / pro-Russian Pan-Slavism / Pan-Eurasianism, as well as Pan-Turanism and similar crap from the 19th century) going down the toilet with each new paper.

    #EDIT (5 OCT 2018): It seems I was too quick to rant about the consequences of the paper without taking into account the complexity of the data presented. Not the first time this impulsivity happens, I guess it depends on my mood and on the time I have to write a post on the specific work day…

    While the data on Srubna, Cimmerians, and Sarmatians shows clearer Y-DNA bottlenecks (of R1a-Z645 subclades) with the new data, the Scythian samples remain controversial, because of the many doubts about the haplogroups (although the most certain cases are R1b-Z2103), their actual date, and cultural attribution. However, I doubt they belong to other peoples, given the expansionist trends of steppe nomads before, during, and after Scythians (as shown in statistical analyses), so most likely they are Scythian or ‘Para-Scythian’ nomadic groups that probably came from the east, whether or not they incorporated Balkan populations. This is further supported by the remaining R1b-P312 and R1b-Z2103 populations in and around the modern Eurasian steppe region.

    scythian-peoples-balkans
    Early Iron Age cultures of the Carpathian basin ca. 7-6th century BC, including steppe groups Basarabi and Scythians. Ďurkovič et al. (2018).

    You can find an interesting and detailed take on the data published (in Russian) at Vol-Vlad’s LiveJournal (you can read an automatic translation from Google). I think that post is maybe too detailed in debunking all information associated to the supposed Scythians – to the point where just a single sample seems to be an actual Scythian (?!) -, but is nevertheless interesting to read the potential pitfalls of the study.

    Related