Bronze Age cultures in the Tarim Basin and the elusive Proto-Tocharians

andronovo-xiaohe-horizon

Master’s thesis Shifting Memories: Burial Practices and Cultural Interaction in Bronze Age China: A study of the Xiaohe-Gumugou cemeteries in the Tarim Basin, by Yunyun Yang, Uppsala University, Department of Archaeology and Ancient History (2019).

Summary excerpts, mainly from the conclusions (emphasis mine):

Both the Xiaohe and the Gumugou groups are suggested as possibly originating from southern Siberia or Central Asia and being related to Afanasievo and Andronovo people (Han 1986, 1994; Li et al. 2010, 2015). But a latest research suggest that the Xiaohe males are genetic distinct from the Afanasievo males, considering the paternal lineages (Hollard et al. 2018). From genetic evidence, it is suggested that southern Siberia and Central Asia were dominated by Europeans during the Bronze Age. Southern Siberia was predominant by Europeans since the Bronze Age as a result of eastward migration of Kurgan people (Keyser et al. 2009). Central Asia started to have an eastern Eurasian maternal lineage that coexisted with the previous western maternal lineage from around 700 BCE (Lalueza-Fox et al. 2004). Based on the research mentioned above, we can conclude as that the Xiaohe and the Gumugou people possibly came from the southern Siberia or Central Asia.

Origin of the Xiaohe horizon

There are two hypotheses about the origins of the Xiaohe horizon. The “steppe hypothesis” assumes that the early settlers (Gumugou people) of the Tarim Basin came from the Afanasievo culture in the Minusinsk Basin-Altai Mountains regions (Kuz’mina et al. 2008; Mallory et al. 2008). The “oasis hypothesis” argues that the early settlers were related to the spreading of the oasis-based agricultural groups from the Bactria and Margiana parts of the southern Central Asia area (Chen et al. 1995). Both hypotheses mainly relied on the use of some materials such as animal cattle, sheep/goats, camel hair, and plant wheat, whose origins were bound to western traditions. But these proofs cannot provide enough support to claim that the Xiaohe horizon cultures were from Afanasievo or BMAC cultures, except for telling there were possible cultural connections or interactions among them. What’s more, there were no horses or potteries in the Xiaohe horizon.

It is worth noting that Ephedra plant is commonly thought as a strong candidate of the Soma or Haoma sacred drink for the ancient Indians or Iranians. Soma is the name recorded in the Vedic Brahmanism religious literature Rigveda, Haoma in the Zoroastrianism Avesta, and indicates as a ritual drink from plant juice. The reason to address Ephedra plant to Soma-Haoma drink is mainly because of its ephedrine, which works on muscle strength, low blood pressure, (and asthma) to make people get rid of tiredness (Houben 2013). Furthermore, it is thought that Ephedra with anti-fatigue function gives gods or the dead immortality, longevity, and resurrection (Mahdihassan 1987). From a mobile consideration of Vedic Aryans perspective, it is thought Vedic Aryans made use of Ephedra, cannabis and poppy to produce Soma drink in Margiana, only Ephedra in Bactria and in Indian mountains area, but other substitutes in Indian plains (Shah 2014). From the Ephedra perspective, it is agreeable that the Xiaohe-Gumugou people were related to the Indo-Aryan peoples (Mallory et al. 1997; Wang 2017).

gumugou-xiaohe
The distribution map of the sites in the Xiaohe cultural horizon.

Burial customs

Both the Xiaohe and the Gumugou groups maintained similar burial customs, but we can distinguish a developing process from the slight diverse ways of the Gumugou cemetery to the highly consistent and advanced technology in making coffins of the Xiaohe cemetery. In terms of the dressing, the dead wore a felt cap, a pair of leather boots, a bracelet twined on the right wrist, and was wrapped in a big felt mantle. The dead in the Xiaohe cemetery also wore a loin-cloth. Commonly, both cemeteries contained burials goods of Ephedra twigs, grains of wheat and millet, grass-made baskets, animal ears (such as calf ears), and livestock. Wooden coffins in the two cemeteries were constructed in a similar way, by assembling two side-planks, two end-boards, a lid consisting of a few short straight boards, and covered with livestock hide (mainly cattle hide in the Xiaohe cemetery and sheep/goats hide in the Gumugou cemetery).

Considering the similar and continuous burial behaviours in the two cemeteries, it can be assumed that both the Xiaohe and the Gumugou societies were stable and consistent. The Xiaohe cemetery had both the special clay-lid wooden coffins and the normal coffins in its early phase (burial layers 4th-5th), then turned to be stable and consistent with the normal coffins (burial layers 1st-3rd), and have developed better construction of the boat-shape coffins. The Gumugou cemetery contained two main burial patterns, type I; the sun-radiating-spokes burials and type II; the normal burials, which coexisted during the same time. Burials of type II were similar but not limited to strict rules. Burials in both the Xiaohe and the Gumugou cemetery were fairly heterogeneous, and the clay-lid wooden coffins in the Xiaohe cemetery and the sun-radiating-spokes burials in the Gumugou cemetery only took up in a small percentage of each cemetery. These special burial types could indicate special roles of the dead in their related societies. Either the dead had high social positions or possibly they actually had a different ancestry origin. It is argued here that the latter is something that is quite possible, considering the mixed populations in the two cemeteries.

The sun-radiating-spokes burials share some features with a similar type of grave, constructed of circular stone kerbs of the stone-pit graves. The sun-radiating-spokes burials might represent an adaption to the local desert environment, which had better access to wood rather than stones. Circular stone kerbs with stone-pit in centre were widely seen in Bronze Age Afanasievo and Andronovo burials, and also in the late Bronze Age and early Iron Age burials along the Tian Shan. The present study suggests a high possibility that the six males buried in the sun-radiating-spokes graves came from the contemporary parallel Andronovo horizon, and kept some of their own ancestry memories in an adapted way.

xinjiang-afanasievo-andronovo-bmac-tian-shan
An assumption of the spreading/expansion routes stone burial constructAn assumption of the spreading/expansion routes stone burial construct.

Societies

Although the Xiaohe and Gumugou societies were stable and consistent, it does not mean that the societies were isolated, and we can see strong indications of them being open to the outside. With time, the Xiaohe population were getting even more diverse origins, as newcomers kept joining the group from outside. However, the burial behaviours in the Xiaohe cemetery did not change as a consequence if these additions. This suggests that the newcomers inherited the local burial customs, and strongly indicates that they became part of the community and adopted the new social identity, possibly through marriage. As a result, the diverse populations can well explain the coexistence of different cultural elements in the burials, e.g. cattle, sheep/goats, camel hair (from Central Asia), grains of wheat (from the west) and millet (from the east), etc.

The Xiaohe and the Gumugou societies were similar, but the Xiaohe society developed to a more advanced level both in economy and in social structure. First, the oasis-based economic system of the Xiaohe and the Gumugou had similar husbandry, but later this was developed to different extent. Both societies mainly relied on livestock, and while the Xiaohe people favoured cattle, the Gumugou people favoured sheep/goats. The two societies also developed agriculture, which can be seen from the grains of wheat and millet. It has been shown that grains of wheat are bread wheat. The Xiaohe people also cooked porridge with millet and milk, and had dairy products.

From these evidences, we can assume that the Xiaohe people have developed a stronger economic level. Secondly, the Xiaohe society had more distinguished gender roles, resulting in different social roles for men and women in terms of work and religions. The female and male dead were buried in a distinguished way with loin-cloths and wooden monuments. Sexual identity on a social level refers to how people consider and expect different genders to act and behave under the social and cultural framework. In the Xiaohe society, men carried out hunting tasks (creatures like vultures, badgers, lizards, snakes); women were associated to the rebirth of lives. To synthesize, a possible relation between the Xiaohe and the Gumugou societies is that they represent two parallel groups who shared similar economic systems because of the similar environment, or that there is a chronological difference where the Gumugou people may have existed earlier. The absolute dating information from the two cemeteries is insufficient to rule out the second situation.

tarim-basin-regions
The area division of the Tarim Basin and its surroundings (The division is made based on the mountain ranges including Altai Mountains, Tian Shan, and Kunlun Mountains, and also the distribution of ancient cemeteries in the whole Xinjiang generally.)

Surroundings

To place the Xiaohe horizon in the larger context of the Bronze Age burials in its surroundings, the hypothesis presented in this study is that the Xiaohe-Gumugou people might possibly represent a parallel to the Andronovo groups, with an eastward migration, that developed their own societies and ethnicities in the Tarim Basin with some ancestral memories still preserved. Considering the location and the geographical features of Xinjiang, the Altai Mountains and the Tian Shan left open access from the Eurasian Steppe to the Dzungarian Basin. The Hami Basin-the Balikun Grassland was the first intersection area to combine the possible western and eastern cultural influences. To pass by the Turpan Basin and enter into the Tarim Basin, there were two possible routes, one northern route along the southern edge of Tian Shan, and one southern route along the northern edge of Kunlun Mountains.

In the early Bronze Age, the burials in Xinjiang had some clear typical geographic features that distinguish them from their surroundings. But from the late Bronze Age to the early Iron Age, the tradition with circular kerbs of stones with stone-pits burials expanded along the southern edge of the Tian Shan, which was a major shift of burial practice that possibly could be linked to the expansion of the Andronovo horizon or a general nomadic expansion.

Although there were no horses or wagons found in the Xiaohe burials, the wooden horse-hoof objects were an indication of horses, which did not exist in their daily lives anymore, but possibly were related to some settlers’ ancestral memories of their nomadic origins. However, it was more important for them to assimilate to the common social identities of their new group. After people died, it was preferred to be buried in the communal cemetery. Even if the dead bodies were lost, wooden substitutes will be used in graves to represent the dead, since they believed in afterlife and thought that the end of the death is rebirth.

Comments

While the results of Li et al. (2010, 2015) of Xiaohe mummies regarding Y-chromosome haplogroups – showing mostly R1a(xZ93) – and radiocarbon dates of the samples are yet to be confirmed, Proto-Tocharians are known to have had contacts with Samoyeds, early Indo-Iranians (in turn in contact with the BMAC language), then into Common Tocharian with ancient Iranians, and then Indo-Aryan and Iranian languages again (for more on this, see Ged Carling‘s publications).

The connection of the Tocharian branch with Afanasevo is essentially indisputable today, like that of Late Proto-Indo-European with late Repin/early Yamna, even more so than it was just 10 years ago, thanks to the most recent genetic investigation. The common genetic stock of Yamna and Afanasevo – as well as that of East Bell Beakers and Palaeo-Balkan peoples – fits perfectly earlier predictions based on the linguistic estimates of the separation and evolution of the diverse language communities, and the tentative attribution to Eurasian steppe-related cultures.

early-bronze-age-tocharian-chemurchek
Tentative identification of language groups among Early Bronze Age cultures. Pre-/Proto-Tocharian is traditionally associated with Chemurchek. See full image.

The trail leading from Afanasevo to Common Tocharians, on the other hand, seems to be more tricky, not unlike many other Indo-European-speaking groups from Europe and Asia, whose precise evolution until their historical attestation is often unclear. Nevertheless, the eventual presence of diverse haplogroups among historical Tocharians – whether they coincide with ancient DNA recovered from BMAC, South India, Andronovo, or Bronze Age Tian Shan populations – will only be relevant to understand the genetic evolution of the speakers of Tocharian during its different stages.

If the genetic trail backwards from known Tocharians to (earlier) unknown Common Tocharians, and forwards from known Pre-Tocharians to (later) unknown Proto-Tocharians leads unequivocally to these populations from the Xiaohe cultural horizon, this paper shows one of the mechanisms through which peoples of the Andronovo cultural horizon (or, more precisely, male lines derived from it) may have become integrated into a Tocharian-speaking population, not dissimilar to what happened in the steppes between Uralic-speaking Abashevo and Pre-Proto-Indo-Iranian-speaking Catacomb-Poltavka to form the Proto-Indo-Iranian-speaking Sintashta-Potapovka-Filatovka culture.

As we have discussed in this blog many times over, to solve this ethnolinguistic identification of prehistoric cultures one needs to investigate ancient DNA in combination with linguistic guesstimates and the Indo-European homeland problem from a wide anthropological perspective. People not understanding this simple concept are bound to end up in some comical Tocharo-Indo-Iranian grouping related to Corded Ware ancestry from Andronovo, similar to the Celto-Ibero-Basques of elevated CEU BA ancestry and hg. R1b-P312 to the south of the Pyrenees during the Iron Age from Olalde et al. (2019), and to the Balto-Finno-Slavs of hg. R1a-Z283 and elevated “Steppe ancestry” in the BA-IA East Baltic from Saag et al. (2019)

Related

“Steppe ancestry” step by step: Khvalynsk, Sredni Stog, Repin, Yamna, Corded Ware

dzudzuana_pca-large

Wang et al. (2018) is obviously a game changer in many aspects. I have already written about the upcoming Yamna Hungary samples, about the new Steppe_Eneolithic and Caucasus Eneolithic keystones, and about the upcoming Greece Neolithic samples with steppe ancestry.

An interesting aspect of the paper, hidden among so many relevant details, is a clearer picture of how the so-called Yamnaya or steppe ancestry evolved from Samara hunter-gatherers to Yamna nomadic pastoralists, and how this ancestry appeared among Proto-Corded Ware populations.

anatolia-neolithic-steppe-eneolithic
Image modified from Wang et al. (2018). Marked are in orange: equivalent Steppe_Maykop ADMIXTURE; 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 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.”

Please note: arrows of “ancestry movement” in the following PCAs do not necessarily represent physical population movements, or even ethnolinguistic change. To avoid misinterpretations, I have depicted arrows with Y-DNA haplogroup migrations to represent the most likely true ethnolinguistic movements. Admixture graphics shown are from Wang et al. (2018), and also (the K12) from Mathieson et al. (2018).

1. Samara to Early Khvalynsk

The so-called steppe ancestry was born during the Khvalynsk expansion through the steppes, probably through exogamy of expanding elite clans (eventually all R1b-M269 lineages) originally of Samara_HG ancestry. The nearest group to the ANE-like ghost population with which Samara hunter-gatherers admixed is represented by the Steppe_Eneolithic / Steppe_Maykop cluster (from the Northern Caucasus Piedmont).

Steppe_Eneolithic samples, of R1b1 lineages, are probably expanded Khvalynsk peoples, showing thus a proximate ancestry of an Early Eneolithic ghost population of the Northern Caucasus. Steppe_Maykop samples represent a later replacement of this Steppe_Eneolithic population – and/or a similar population with further contribution of ANE-like ancestry – in the area some 1,000 years later.

PCA-caucasus-steppe-samara

This is what Steppe_Maykop looks like, different from Steppe_Eneolithic:

steppe-maykop-admixture

NOTE. This admixture shows how different Steppe_Maykop is from Steppe_Eneolithic, but in the different supervised ADMIXTURE graphics below Maykop_Eneolithic is roughly equivalent to Eneolithic_Steppe (see orange arrow in ADMIXTURE graphic above). This is useful for a simplified analysis, but actual differences between Khvalynsk, Sredni Stog, Afanasevo, Yamna and Corded Ware are probably underestimated in the analyses below, and will become clearer in the future when more ancestral hunter-gatherer populations are added to the analysis.

2. Early Khvalynsk expansion

We have direct data of Khvalynsk-Novodanilovka-like populations thanks to Khvalynsk and Steppe_Eneolithic samples (although I’ve used the latter above to represent the ghost Caucasus population with which Samara_HG admixed).

We also have indirect data. First, there is the PCA with outliers:

PCA-khvalynsk-steppe

Second, we have data from north Pontic Ukraine_Eneolithic samples (see next section).

Third, there is the continuity of late Repin / Afanasevo with Steppe_Eneolithic (see below).

3. Proto-Corded Ware expansion

It is unclear if R1a-M459 subclades were continuously in the steppe and resurged after the Khvalynsk expansion, or (the most likely option) they came from the forested region of the Upper Dnieper area, possibly from previous expansions there with hunter-gatherer pottery.

Supporting the latter is the millennia-long continuity of R1b-V88 and I2a2 subclades in the north Pontic Mesolithic, Neolithic, and Early Eneolithic Sredni Stog culture, until ca. 4500 BC (and even later, during the second half).

Only at the end of the Early Eneolithic with the disappearance of Novodanilovka (and beginning of the steppe ‘hiatus’ of Rassamakin) is R1a to be found in Ukraine again (after disappearing from the record some 2,000 years earlier), related to complex population movements in the north Pontic area.

NOTE. In the PCA, a tentative position of Novodanilovka closer to Anatolia_Neolithic / Dzudzuana ancestry is selected, based on the apparent cline formed by Ukraine_Eneolithic samples, and on the position and ancestry of Sredni Stog, Yamna, and Corded Ware later. A good alternative would be to place Novodanilovka still closer to the Balkan outliers (i.e. Suvorovo), and a source closer to EHG as the ancestry driven by the migration of R1a-M417.

PCA-sredni-stog-steppe

The first sample with steppe ancestry appears only after 4250 BC in the forest-steppe, centuries after the samples with steppe ancestry from the Northern Caucasus and the Balkans, which points to exogamy of expanding R1a-M417 lineages with the remnants of the Novodanilovka population.

steppe-ancestry-admixture-sredni-stog

4. Repin / Early Yamna expansion

We don’t have direct data on early Repin settlers. But we do have a very close representative: Afanasevo, a population we know comes directly from the Repin/late Khvalynsk expansion ca. 3500/3300 BC (just before the emergence of Early Yamna), and which shows fully Steppe_Eneolithic-like ancestry.

afanasevo-admixture

Compared to this eastern Repin expansion that gave Afanasevo, the late Repin expansion to the west ca. 3300 BC that gave rise to the Yamna culture was one of colonization, evidenced by the admixture with north Pontic (Sredni Stog-like) populations, no doubt through exogamy:

PCA-repin-yamna

This admixture is also found (in lesser proportion) in east Yamna groups, which supports the high mobility and exogamy practices among western and eastern Yamna clans, not only with locals:

yamnaya-admixture

5. Corded Ware

Corded Ware represents a quite homogeneous expansion of a late Sredni Stog population, compatible with the traditional location of Proto-Corded Ware peoples in the steppe-forest/forest zone of the Dnieper-Dniester region.

PCA-latvia-ln-steppe

We don’t have a comparison with Ukraine_Eneolithic or Corded Ware samples in Wang et al. (2018), but we do have proximate sources for Abashevo, when compared to the Poltavka population (with which it admixed in the Volga-Ural steppes): Sintashta, Potapovka, Srubna (with further Abashevo contribution), and Andronovo:

sintashta-poltavka-andronovo-admixture

The two CWC outliers from the Baltic show what I thought was an admixture with Yamna. However, given the previous mixture of Eneolithic_Steppe in north Pontic steppe-forest populations, this elevated “steppe ancestry” found in Baltic_LN (similar to west Yamna) seems rather an admixture of Baltic sub-Neolithic peoples with a north Pontic Eneolithic_Steppe-like population. Late Repin settlers also admixed with a similar population during its colonization of the north Pontic area, hence the Baltic_LN – west Yamna similarities.

NOTE. A direct admixture with west Yamna populations through exogamy by the ancestors of this Baltic population cannot be ruled out yet (without direct access to more samples), though, because of the contacts of Corded Ware with west Yamna settlers in the forest-steppe regions.

steppe-ancestry-admixture-latvia

A similar case is found in the Yamna outlier from Mednikarovo south of the Danube. It would be absurd to think that Yamna from the Balkans comes from Corded Ware (or vice versa), just because the former is closer in the PCA to the latter than other Yamna samples. The same error is also found e.g. in the Corded Ware → Bell Beaker theory, because of their proximity in the PCA and their shared “steppe ancestry”. All those theories have been proven already wrong.

NOTE. A similar fallacy is found in potential Sintashta→Mycenaean connections, where we should distinguish statistically that result from an East/West Yamna + Balkans_BA admixture. In fact, genetic links of Mycenaeans with west Yamna settlers prove this (there are some related analyses in Anthrogenica, but the site is down at this moment). To try to relate these two populations (separated more than 1,000 years before Sintashta) is like comparing ancient populations to modern ones, without the intermediate samples to trace the real anthropological trail of what is found…Pure numbers and wishful thinking.

Conclusion

Yamna and Corded Ware show a similar “steppe ancestry” due to convergence. I have said so many times (see e.g. here). This was clear long ago, just by looking at the Y-chromosome bottlenecks that differentiate them – and Tomenable noticed this difference in ADMIXTURE from the supplementary materials in Mathieson et al. (2017), well before Wang et al. (2018).

This different stock stems from (1) completely different ancestral populations + (2) different, long-lasting Y-chromosome bottlenecks. Their similarities come from the two neighbouring cultures admixing with similar populations.

If all this does not mean anything, and each lab was going to support some pre-selected archaeological theories from the 1960s or the 1980s, coupled with outdated linguistic models no matter what – Anthony’s model + Ringe’s glottochronological tree of the early 2000s in the Reich Lab; and worse, Kristiansen’s CWC-IE + Germano-Slavonic models of the 1940s in the Copenhagen group – , I have to repeat my question again:

What’s (so much published) ancient DNA useful for, exactly?

See also

Related

Yamna/Afanasevo elite males dominated by R1b-L23, Okunevo brings ancient Siberian/Asian population

afanasevo-okunevo

Open access paper New genetic evidence of affinities and discontinuities between bronze age Siberian populations, by Hollard et al., Am J Phys Anthropol. (2018) 00:1–11.

NOTE. This seems to be a peer-reviewed paper based on a more precise re-examination of the samples from Hollard’s PhD thesis, Peuplement du sud de la Sibérie et de l’Altaï à l’âge du Bronze : apport de la paléogénétique (2014).

Interesting excerpts:

Afanasevo and Yamna

The Afanasievo culture is the earliest known archaeological culture of southern Siberia, occupying the Minusinsk-Altai region during the Eneolithic era 3600/3300 BC to 2500 BC (Svyatko et al., 2009; Vadetskaya et al., 2014). Archeological data showed that the Afanasievo culture had strong affinities with the Yamnaya and pre-Yamnaya Eneolithic cultures in the West (Grushin et al., 2009). This suggests a Yamnaya migration into western Altai and into Afanasievo. Note that, in most current publications, “the Yamnaya culture” combines the so-called “classical Yamnaya culture” of the Early Bronze Age and archeological sites of the preceding Repin culture in the middle reaches of the Don and Volga rivers. In the present article we conventionally use the term Yamnaya in the same sense, in which case the beginning of the “Yamnaya culture” can be dated after the middle of the 4th millennium BC, when the Afanasievo culture appeared in the Altai.

Because of numerous traits attributed to early Indo-Europeans and cultural relations with Kurgan steppe cultures, members of the Afanasievo culture are believed to have been Indo-European speakers (Mallory and Mair, 2000). In a recent whole-genome sequencing study, Allentoft et al. (2015) concluded that Eastern Yamnaya individuals and Afanasievo individuals were genetically indistinguishable. Moreover, this study and one published concurrently by Haak et al. (2015) analyzed 11 Eastern Yamnaya males and showed that all of them belonged to the R1b1a1a (formerly R1b1a) (…)

indo-european-uralic-migrations-afanasevo
Early Chalcolithic migrations ca. 3300-2600 BC.

Published works indicate that R1b was a predominant haplogroup from the late Neolithic to the early Bronze Age, notably in the Bell Beaker and Yamnaya cultures (Allentoft et al., 2015; Haak et al., 2015; Lee et al., 2012; Mathieson et al., 2015). Nearly 100% of the Afanasievo men we typed belonged to the R1b1a1a subhaplogroup and, for at least three of them, more precisely to the L23 (xM412) subclade. (…)

(…) our results therefore support the hypothesis of a genetic link between Afanasievo and Yamnaya. This also suggests that R1b was indeed dominant in the early Bronze Age Siberian steppe, at least in individuals that were buried in kurgans (possibly an elite part of the population). The geographical and temporal distribution of subhaplogroup R1b1a1a supports the hypothesis of population expansion from West to East in the Eurasian steppe during this period. It should however be noted that the Yamnaya burials from which the samples for DNA analysis were obtained (Allentoft et al., 2015; Haak et al., 2015; Mathieson et al., 2015) were dated within the limits of the Afanasievo period. Ancestors of both East Yamnaya and Afanasievo populations must therefore be sought in the context of earlier Eneolithic cultures in Eastern Europe. Sufficient Y-chromosomal data from such Eneolithic populations is, unfortunately, not yet available.

mtdna-ydna-afanasevo-okunevo
Mitochondrial- (A) and Y- (B) haplogroup distribution in studied populations

Okunevo and paternal lineage shift in South Siberia

Results obtained in the current study, from more than a dozen Okunevo individuals belonging to the earliest stage of Okunevo culture, that is the Uibat period (2500–2200 BC) (Lazaretov, 1997), suggest a discontinuity in the genetic pool between Afanasievo and Okunevo cultures. Although Y-chromosomal data obtained for bearers of the Okunevo culture showed that one individual carried haplogroup R1b, most Okunevo Y-haplogroups are representative of an Asian component represented by paternal lineages Q and NO1.

Okunevo carrier of Y-haplogroup Q1b1a-L54, which also supports this hypothesis (L54 being a marker of the lineage from which M3, the main Ameridian lineage, arose). Okunevo people could therefore be a remnant paleo-Siberian population with possible Afanasievo input, as suggested by the presence of the R1b1a1a2a subhaplogroup in one individual.

indo-european-uralic-migrations-afanasevo-late
Late Chalcolithic migrations ca. 2600-2250 BC.

Replacement of Asian Indo-European elite lineages by R1a

Published genetic data from the late Bronze Age Andronovo culture from the Minusinsk Basin (Keyser et al., 2009), the Sintashta culture from Russia (Allentoft et al., 2015) and the Srubnaya culture from the region of Samara (Mathieson et al., 2015), show that males did not belong to Y-haplogroup R1b but mostly to R1a clades: there appears to have been a change in the dominant Y-chromosomal haplogroup between the early and the late Bronze Age in these regions. Moreover, as described in Allentoft et al. (2015), the Andronovo and Sintashta peoples were closely related to each other but clearly distinct from both Yamnaya and Afanasievo. Although these results do not imply that Y-haplogroup R1b was entirely absent in these later populations, they could correspond to a replacement of the elite between these two main periods and therefore a difference in the haplogroups of the men that were preferentially buried.

indo-european-uralic-migrations-okunevo-andronovo
Early Bronze Age migrations ca. 2250-1750 BC.

Afanasevo and the Tarim Basin

The discovery, in the Tarim Basin, of well-preserved mummies from the Bronze Age allows for the construction of two hypotheses regarding the peopling of the Xinjiang province at this period. The “steppe hypothesis,” argues for a link with nomadic steppe herders (Hemphill and Mallory, 2004), possibly represented in this case by Afanasievo populations and their descendants (Mallory and Mair, 2000). However, newly published cultural data from the burial grounds of Gumugou (Wang, 2014) and Xiaohe (Xinjiang, 2003, 2007) shows material culture and burial rites incompatible with the Afanasievo culture. The earliest 14C date for Tarim Basin burials would place them at the turn of the 2nd millenium BC (Wang, 2013), 500 years after the Afanasievo period.

Instead, early Gumugou and Xiaohe burial grounds were contemporary with the start of the Andronovo period. Likewise, the Bronze Age population of the Xinjiang at Gumugou/Qäwrighul is not phenotypically closest to Afanasievo but to the Andronovo (Fedorovo) group of northeastern Kazakhstan and western Altai (Kozintsev, 2009). Our investigations demonstrate that Y-chromosomal lineage composition is also compatible with the notion that the ancient Tarim population was genetically distinct from the Afanasievo population. The only Y-haplogroup found by Li et al. (2010) in the Bronze Age Tarim Basin population was Y-haplogroup R1a, which suggests a proximity of this population with Andronovo groups rather than Afanasievo groups.

I don’t think these finds are much of a surprise based on what we already know, or need much explanation…

I would add that, once again, we have more proof that the movement of Okunevo and related ancient Siberian migrants from Central or North Asia will not be able to explain the presence of Uralic languages spread over North-East Europe and Scandinavia already during the Bronze Age.

Also interesting is to read in more peer-reviewed papers the idea of Late Indo-European speakers clearly linked to the expansion of patrilineally-related elite males marked by haplogroup R1b-L23, most likely since Eneolithic Khvalynsk/Repin cultures.

Related: