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 Pro-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. Q1a2-M25 (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 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. Q1a2-M25, and at least one Q1a1-B284, 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 Q1a2-M25 (in particular Q1a2-L712), and hg. Q reported from Elunino, Sagsai, Khövsgöl, and also among peoples of the Srubna-Andronovo horizon (the Krasnoyarsk MLBA outlier), and in Karasuk. Q1a-M25 was earlier found in a Baltic hunter-gatherer, which supports a widespread distribution of Q1a2 and Q1a1 in North Eurasia during the Neolithic and Bronze Age.

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

A study of genetic diversity of three isolated populations in Xinjiang using Y-SNP

indo-european-indo-iranian-migrations

New open access paper (in Chinese) A study of genetic diversity of three isolated populations in Xinjiang using Y-SNP, by liu et al. Acta Anthropologica Sinitica (2018)

Abstract:

The Keriyan, Lopnur and Dolan peoples are isolated populations with sparse numbers living in the western border desert of our country. By sequencing and typing the complete Y-chromosome of 179 individuals in these three isolated populations, all mutations and SNPs in the Y-chromosome and their corresponding haplotypes were obtained. Types and frequencies of each haplotype were analyzed to investigate genetic diversity and genetic structure in the three isolated populations. The results showed that 12 haplogroups were detected in the Keriyan with high frequencies of the J2a1b1 (25.64%), R1a1a1b2a (20.51%), R2a (17.95%) and R1a1a1b2a2 (15.38%) groups. Sixteen haplogroups were noted in the Lopnur with the following frequencies: J2a1 (43.75%), J2a2 (14.06%), R2 (9.38%) and L1c (7.81%). Forty haplogroups were found in the Dolan, noting the following frequencies: R1b1a1a1 (9.21%), R1a1a1b2a1a (7.89%), R1a1a1b2a2b (6.58%) and C3c1 (6.58%). These data show that these three isolated populations have a closer genetic relationship with the Uygur, Mongolian and Sala peoples. In particular, there are no significant differences in haplotype and frequency between the three isolated populations and Uygur (f=0.833, p=0.367). In addition, the genetic haplotypes and frequencies in the three isolated populations showed marked Eurasian mixing illustrating typical characteristics of Central Asian populations.

population-distribution-map
Figure 1. The populations distribution map. Left: Uluru. Center: Dali Yabuyi. Right: Kaerqu.

My knowledge of written Chinese is almost zero, so here are some excerpts with the help of Google Translate:

The source of 179 blood samples used in the study is shown in Figure 1. The Keriyan blood samples were collected from Dali Yabuyi Township, Yutian County (39 samples). The blood samples of the Lopnur people were collected from Kaerqu Township, Yuli County (64 cases); the blood samples of the Dolan people were collected from the town of Uluru, Awati County (76).

haplotype-frequency-uighur
Columns one and two are the Keriyan haplotypes and frequencies, respectively; the third and fourth columns are the Lopnur haplotypes and frequencies; the last four columns are the Daolang haplotypes and frequencies.

The composition and frequency of the Keriyan people’s haplogroup are closest to those of the Uighurs, and both Principal Component Analysis and Phylogenetic Tree Analysis show that their kinship is recent. We initially infer that the Keriyan are local desert indigenous people. They have a connection with the source of the Uighurs. Chen et al. [42] studied the patriarchal and maternal genetic analysis of the Keriyan people and found that they are not descendants of the Tibetan ethnic group in the West. The Keriyan people are a mixed group of Eastern and Western Europeans, which may originate from the local Vil group. Duan Ranhui [43] and other studies have shown that the nucleotide variability and average nucleotide differences in the Keriyan population are between the reported Eastern and Western populations. The phylogenetic tree also shows that the populations in Central Asia are between the continental lineage of the eastern population and the European lineage of the western population, and the genetic distance between the Keriyan and the Uighurs is the closest, indicating that they have a close relationship.

y-chromosome-pca

Regarding the origin of the Lopnur people, Purzhevski judged that it was a mixture of Mongolians and Aryans according to the physical characteristics of the Lopnur people. In 1934, the Sino-Swiss delegation discovered the famous burials of the ancient tombs in the Peacock River. After research, they were the indigenous people before the Loulan period; the researcher Yang Lan, a researcher at the Institute of Cultural Relics of the Chinese Academy of Social Sciences, said that the Lopnur people were descendants of the ancient “Landan survivors”. However, the Loulan people speaking an Indo-European language, and the Lopnur people speaking Uyghur languages contradict this; the historical materials of the Western Regions, “The Geography of the Western Regions” and “The Western Regions of the Ming Dynasty” record the Uighurs who lived in Cao Cao in the late 17th and early 18th centuries. Because of the occupation of the land by the Junggar nobles and their oppression, they fled. Some of them were forced to move to the Lop Nur area. There are many similar archaeological discoveries and historical records. We have no way to determine their accuracy, but they are at different times, and there is a great difference in what is heard in the same region. (…) The genetic characteristics of modern Lopnur people are the result of the long-term ethnic integration of Uyghurs, Mongols, and Europeans. This is also consistent with the similarity of the genetic structure of the Y chromosome of Lopnur in this study with the Uighurs and Mongolians. For example, the frequency of J haplogroup is as high as 59.37%, while J and its downstream sub-haplogroup are mainly distributed in western Europe, West Asia and Central Asia; the frequency of O, R haplogroup is close to that of Mongolians.

y-chromosome-frequency
1) KA: Keriya, LB: Rob, DL: Daolang, HTW: Hetian Uygur, HTWZ: and Uygur, TLFW: Turpan Uighur, HZ: Hui, HSKZ: Kazakh, WZBKZ: Wuhuan Others, TJKZ: Tajik, KEKZZ: Kirgiz, TTEZ: Tatar, ELSZ: Russian XBZ: Xibo, MGZ: Mongolian, SLZ: Salar, XJH: Xinjiang Han, GSH: Gansu Han, GDH: Guangdong Han SCH: Sichuan Han. 2) Reference population data source literature 19-22. After the population names in the table have been marked, all the shorthands in the text are referred to in this table. 3) Because the degree of haplotypes of each reference population is different to each sub-group branch, the sub-group branches under the same haplogroup are merged when the population haplogroup data is aggregated, for example: for haplogroup G Some people are divided into G1a and G2a levels, others are assigned to G1, G2, and G3, while some people can only determine G this time. Therefore, each subgroup is merged into a single group G.

According to Ming History·Western Biography, the Mongolians originated from the Mobei Plateau and later ruled Asia and Eastern Europe. Mongolia was established, and large areas of southern Xinjiang and Central Asia were included. Later, due to the Mongolian king’s struggle for power, it fell into a long-term conflict. People of the land fled to avoid the war, and the uninhabited plain of the lower reaches of the Yarkant River naturally became a good place to live. People from all over the world gathered together and called themselves “Dura” and changed to “Dang Lang”. The long-term local Uyghur exchanges that entered the southern Mongolian monks and “Dura” were gradually assimilated [44]. According to the report, locals wore Mongolian clothes, especially women who still maintained a Mongolian face [45]. In 1976, the robes and waistbands found in the ancient time of the Daolang people in Awati County were very similar to those of the ancients. Dalang Muqam is an important part of Daolang culture. It is also a part of the Uyghur Twelve Muqam, and it retains the ancient Western culture, but it also contains a larger Mongolian culture and relics. The above historical records show that the Daolang people should appear in the Chagatai Khanate and be formed by the integration of Mongolian and Uighur ethnic groups. Through our research, we also found that the paternal haplotype of the Daolang people is contained in both Uygur and Mongolian, and the main haplogroups are the same, whereas the frequencies are different (see Table 3). The principal component analysis and the NJ analysis are also the same. It is very close to the Uyghur and the Mongolian people, which establishes new evidence for the “mixed theory” in molecular genetics.

main-haplogroup-uighur
Genetic relationship between the three isolated populations: the Uygur and the Mongolian is the closest, and the main haplogroup can more intuitively compare the source composition of the genetic structure of each population. Haplogroups C, D, and O are mainly distributed in Asia as the East Asian characteristic haplogroup; haplogroups G, J, and R are mainly distributed in continental Europe, and the high frequency distribution is in Europe and Central Asia.

If the nomenclature follows a recent ISOGG standard, it appears that:

The presence of exclusively R1a-Z93 subclades and the lack of R1b-M269 samples is compatible with the expansion of R1a-Z93 into the area with Proto-Tocharians, at the turn of the 3rd-2nd millennium BC, as suggested by the Xiaohe samples, supposedly R1a(xZ93).

Now that it is obvious from ancient DNA (as it was clear from linguistics) that Pre-Tocharians separated earlier than other Late PIE peoples, with the expansion of late Khvalynsk/Repin into the Altai, at the end of the 4th millennium, these prevalent R1a (probably Z93) samples may be showing a replacement of Pre-Tocharian Y-DNA with the Andronovo expansion already by 2000 BC.

Lacking proper assessment of ancient DNA from Proto-Tocharians, this potential early Y-DNA replacement is still speculative*. However, if that is the case, I wonder what the Copenhagen group will say when supporting this, but rejecting at the same time the more obvious Y-DNA replacement in East Yamna / Poltavka in the mid-3rd millennium with incoming Corded Ware-related peoples. I guess the invention of an Indo-Tocharian group may be near…

*NOTE. The presence of R1b-M269 among Proto-Tocharians, as well as the presence of R1b-M269 among Tarim Basin peoples in modern and ancient times is not yet fully discarded. The prevalence of R1a-Z93 may also be the sign of a more recent replacement by Iranian peoples, before the Mongolian and Turkic expansions that probably brought R1b(xM269).

Also, the presence of R1b (xM269) samples in east Asia strengthens the hypothesis of a back-migration of R1b-P297 subclades, from Northern Europe to the east, into the Lake Baikal area, during the Early Mesolithic, as found in the Botai samples and later also in Turkic populations – which are the most likely source of these subclades (and probably also of Q1a2 and N1c) in the region.

Related

Y-DNA haplogroups of Tuvinian tribes show little effect of the Mongol expansion

uralic-turkic

Open access Estimating the impact of the Mongol expansion upon the gene pool of Tuvans, by Balanovskaya et al., Vavilov Journal of genetics and breeding (2018), 22(5):611-619.

Abstract (emphasis mine):

With a view to trace the Mongol expansion in Tuvinian gene pool we studied two largest Tuvinian clans – those in which, according to data of humanities, one could expect the highest Central Asian ancestry, connected with the Mongol expansion. Thus, the results of Central Asian ancestry in these two clans component may be used as upper limit of the Mongol influence upon the Tuvinian gene pool in a whole. According to the data of 59 Y-chromosomal SNP markers, the haplogroup spectra in these Tuvinian tribal groups (Mongush, N = 64, and Oorzhak, N = 27) were similar. On average, two-thirds of their gene pools (63 %) are composed by North Eurasian haplogroups (N*, N1a2, N3a, Q) connected with autochtonous populations of modern area of Tuvans. The Central Asian haplogroups (C2, O2) composed less then fifth part (17 %) of gene pools of the clans studied. The opposite ratio was revealed in Mongols: there were 10 % North Eurasian haplogroups and 75 % Central Asian haplogroups in their gene pool. All the results derived – “genetic portraits”, the matrix of genetic distances, the dendrogram and the multidimensional scaling plot, which mirror the genetic connections between Tuvinian clans and populations of South Siberia and East Asia, demonstrated the prominent similarity of the Tuvinian gene pools with populations from and Khakassia and Altai. It could be therefore assumed that Tuvinian clans Mongush and Oorzhak originated from autochtonous people (supposedly, from the local Samoyed and Kets substrata). The minor component of Central Asian haplogroups in the gene pool of these clans allowed to suppose that Mongol expansion did not have a significant influence upon the Tuvinan gene pool at a whole.

tuvan-clans-y-dna

Interesting excerpts:

Haplogroup C2 peaks in Central Asia (Wells et al., 2001; Zerial et al., 2003), though its variants are abundant in other peoples of Siberia and Far East. For instance, in one of Buryat clans, namely Ekhirids, hg C2 frequency is 88 % (Y-base); in Kazakhs from different regions of Kazakhstan, total occurrence of hg C2 variants averages between 17 and 81 % (Abilev et al., 2012; Zhabagin et al., 2013, 2014, 2017), in populations of the Amur River (such as Nanais, Negidals, Nivkhs, Ulchs) – between 40 and 65 %, in Evenks – up to 68 % (Y-base), in Kyrgyz people of Pamir-Alay – up to 22 %, correspondingly; of all Turkic peoples of Altai, relatively high hg C2 frequency (16 %) is detected only in Telengits (Balanovskaya et al., 2014; Balaganskaya et al., 2011a, 2016). In Tuvinian clans under the study, hg C2 frequency is rather low – 19 % in Mongush and 11 % in Oorzhak, while in Mongols it makes up almost two thirds of the entire gene pool an comprises different genetic lines (subhaplogroups).

tuvinian-y-chromosome
Y-chromosomal haplogroup spectra in gene pools of Tuvinian Oorzhak and Mongush clans and of the neighboring populations of South Siberia and Central Asia.

Haplogroup N is abundant all over North Eurasia from Scandinavia to Far East (Rootsi et al., 2007). The study on whole Y-chromosome sequencing conducted with participation of our group (Ilumäe et al., 2016) subdivided this haplogroup into several branches with their regional distribution. In gene pools of the Tuvans involved, hg N was represented by two sub-clades, namely N1a2 and N3a.

Sub-clade N1a2 peaks in populations of West Siberia (in Nganasans, frequency is 92 %) and South Siberia (in Khakas 34 %, in Tofalars 25 %) (Y-base). In Tuvans, N1a2 occurrence is nearly 16 % in Mongush and 15 % in Oorzhak clans, respectively, while in Mongols, the frequency is three times less (5 %). Hg N1a2 is supposed to display the impact of the Samoyedic component to the gene pool of Tuvinian clans (Kharkov et al., 2013).

Sub-clade N3a is major in the Oorzhak clan comprising almost half of the gene pool (45 %); it is represented by two sub-clades, namely N3a* and N3a5. The same sub-branches are specific to the Mongush clan as well, though with lower frequencies: N3a* – 9 % and N3a5 – 14 % (see Table). In Khori-Buryats from the Transbaikal region, a high frequency is observed – 82 % (Kharkov et al., 2014), while in Mongols, N3a5 occurs rather rarely (6 %). Hg N3a* was detected in populations of South Siberia only, and was widely spread in Khakas-Sagays and Shors (up to 40 %) (Ilumäe et al., 2016) (Y-base).

samoyedic
Map of distribution of Samoyedic languages (red) in the XVII century (approximate; hatching) and in the end of XX century (continuous background). Modified from Wikipedia, with the Tuva region labelled.

Within the pan-Eurasian haplogroup R1a1a, two large genetic lines (sub-haplogroups) are identified: “European” (marker M458) and “Asian” (marker Z93) the latter almost never occurring in Europe (Balanovsky, 2015) but abundant in South Siberia and northern Hindustan. In the Altai-Sayan region, high frequencies of the “Asian” branch are spread in many peoples – Shors, Tubalars, Altai-Kizhi people, Telengits, Sagays, Kyzyl Khakas, Koibals, Teleuts (Y-base) (Kharkov et al., 2009). Hg R1a1a comprises perceptible parts of gene pools of Tuvinian clans (19 % in Mongush, and 15 % in Oorzhak), though its occurrence in Mongols is much lower (6 %). Those results also count in favor of the hypothesis of autochtonous component dominance even in the gene pools of clans potentially most influenced by Mongolian ancestry. If we add R1a1a variants to the “North Eurasian” haplogroups, the “not-Central Asian” component will compose average four fifth of the entire gene pools for Tuvinian clans (in Mongush 77 %, and in Oorzhak 81 %), being only 16 % in Mongols. Such data are definitely contrary to the hypothesis of a crucial influence of the Mongol expansion upon the development of Tuvinian gene pool.

I found interesting the high proportion of R1a-Z93 subclades among Sagays in Khakhasia, which stem from a local Samoyed substratum, as described by the paper…

Featured Image: Map of Uralic and Altaic languages, from Wikipedia.

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Updated phylogenetic tree of haplogroup Q-M242 points to Palaeolithic expansions

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New paper (behind paywall) Paternal origin of Paleo-Indians in Siberia: insights from Y-chromosome sequences by Wei et al., Eur. J. Hum. Genet. (2018)

Interesting excerpts (for Eurasian migrations):

Differentiation and diffusion in Palaeolithic Siberia

Based on the phylogenetic analyses and the current distributions of relative sub-lineages, we propose that the prehistoric population differentiation in Siberia after the LGM (post-LGM) provided the genetic basis for the emergence of the Paleo-Indian, American aborigine, population. According to the phylogenetic tree of Y-chromosome haplogroup C2-M217 (Fig. 2 and Figure S1), eight sub-lineages emerged in a short period between 15.3 kya and 14.3 kya (Table S5). Within these sub-lineages, haplogroups C2-M48, C2-F1918, and C2- F1756 are predominant paternal lineages in modern Altaic-speaking populations [46, 51, 52]. Samples of haplogroups C2-F8535 and C2-P53.1 were found in two Turkic- and Mongolic-speaking minorities in China (Table S1). Both archeological and genetic data suggest that Altaic-speaking populations are results of population expansion in the past several thousand years in the Altai Mountain, Mongolia Plateau, and Amur River region [51–54].

By contrast, three other sub-lineages, C2-B79, C2-B77, and C2-P39, appear only in Koryaks and Native Americans [16, 35]. The latitude of the Altai Mountain, the Mongolia Plateau, and Amur River region are much lower than that of Beringia, where the ancestors of Native Americans finally separated from their close relatives in Siberia. Therefore, the phylogeographic patterns of sub-lineages of C2-M217 in this study reveal a major splitting event between populations in a lower latitude region of Siberia and ancestors of Koryaks and Native Americans during the post-LGM period.

The sub-lineages of the Y-chromosome Q-M242 haplogroup were found in populations throughout the Eurasia continent. According to available data, the Q1-L804 lineage is exclusively found in Northwest Europe, while Q1-M120 is primarily restricted to East Asia [48]. Additionally, the lineage Q1-L330 is the predominant paternal lineage in Altai, Tuva, and Kets in South Siberia [34–36, 55]. A number of Q1-M242 samples have also been found in ancient remains from South Siberia and adjacent regions [56, 57]. Other sub-lineages of Q-M242 are scattered widely in different geographic regions of Eurasia, including Q1-L275, Q1-M25, and Q1-Y2659 [14, 35, 37, 58]. Additionally, the Y-chromosome of a 6000–5100 BCE sample (I4550) from Zvejnieki, Latvia has been identified as Q1-L56 [59]. These findings suggest that the sub-lineages of Q-M242 started to diffuse throughout Eurasia in a very ancient period.

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Founding paternal lineages of American aborigines and their most closely related lineages among Eurasia populations

Emergence of Paleo-Indian populations

The revised phylogenetic tree of Y-chromosome haplogroup Q-M242 in this study provides clues regarding the origin of Native American lineages Q1-M3 and Q1-Z780 (Fig. 3). According to our estimates, haplogroup Q1-L54 expanded rapidly between 17.2 kya and 15.0 kya and finally gave rise to two major founding paternal lineages of Native American populations, known as Q1-Z780 and Q1-M3. Ancient DNA studies indicate that the early population in South Siberia, represented by MA1 genomes, had a genetic influence on both modern western European and Native American populations [7]. Therefore, we conclude that the accumulated diversity of sub-lineages of Q-M242 before 15.3 kya resulted from the in situ differentiation of Q-M242 in Central Eurasia and South Siberia since the Paleolithic Age, and the appearance of the Paleo-Indian population is part of the great human diffusion throughout the Eurasia after the Last Glacial Maximum.

The Southern Caucasus PIE homeland

PCA-caucasus-lola-ane-chg
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. An EHG and a Caucasus ‘clouds’ have been drawn, leaving Pontic-Caspian steppe and derived groups between them.See the original file here.

The origin of Q-M242 in Zvejnieki, like those of Lola (Q1a2-M25) and Steppe Maykop (Q1a2-M25) from Wang et al. (2018) are therefore most likely migrations throughout North Eurasia dated to the Palaeolithic.

As you might remember, the sample of haplogroup Q1a from Khvalynsk was the closest one (in the PCA, see above) to those we now know most likely represent one or more groups of the steppe north of the Caucasus, which were absorbed during the formation and expansion of Khvalynsk.

NOTE. In fact, the position of this early Khvalynsk sample in the PCA is near the Steppe Eneolithic cluster, in turn near ANE (with the Lola sample Q1a2-M25, circle in dark blue/violet above), and Steppe Maykop (which includes the other Q1a2-M25 sample).

It is often assumed that these populations absorbed in the Pontic-Caspian steppe were dominated by haplogroup J, due to the oldest representatives of CHG ancestry (Kotias Klde and Satsurblia).

However, it would not be surprising now to find out that (one or more of) these “CHG/ANE-rich” groups from the steppe (possibly the Kairshak culture in the North Caspian region) were in fact dominated by Q1-M25 subclades.

If this is the case, I don’t know where the proponents of the (south of the) Caucasus homeland will retreat to.

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