“Steppe ancestry” step by step (2019): Mesolithic to Early Bronze Age Eurasia

yamnaya-gac-maykop-corded-ware-bell-beaker

The recent update on the Indo-Anatolian homeland in the Middle Volga region and its evolution as the Indo-Tocharian homeland in the Don–Volga area as described in Anthony (2019) has, at last, a strong scientific foundation, as it relies on previous linguistic and archaeological theories, now coupled with ancient phylogeography and genomic ancestry.

There are still some inconsistencies in the interpretation of the so-called “Steppe ancestry”, though, despite the one and a half years that have passed since we first had access to the closest Pontic–Caspian steppe source populations. Even my post “Steppe ancestry” step by step from a year ago is already outdated.

Admixture

The population selection process for models shown below included (1) plausibility of potential influences in the particular geographic and archaeological context; (2) looking for their clusters or particular samples in the PCA; and (3) testing with qpAdm for potential source populations that might have been involved in their development.

The results and graphics posted are therefore intended to simplistically show potential admixture events between populations potentially close to the actual sources of the target samples, whenever such mating networks could be supported by archaeology.

NOTE. This is an informal post and I am not a geneticist, so I am turning this flexibility to my advantage. If any reader is – for some strange reason – looking for a strict hypothesis testing, for the use of a full set of formal stats (as used e.g. in Ning et al. 2019 for Proto-Tocharians), and correctly redacted and peer-reviewed text, this is not the right place to find them.

spatial-pedigree-geographic-admixture
An example pedigree (a) of a focal individual sampled in the modern day, placed in its geographic context to make the spatial pedigree (b). Dashed lines denote matings, and solid lines denote parentage, with red hues for the maternal ancestors and blue hues for the paternal ancestors. In the spatial pedigree, each plane represents a sampled region in a discrete (nonoverlapping) generation, and each dot shows the birth location of an individual. The pedigree of the focal individual is highlighted back through time and across space. Image modified from Bradburd and Ralph (2019).

Despite the natural impulse to draw straight mixture trajectories (see e.g. Wang et al. 2019), simply adding or subtracting samples used for a PCA shows how the plot is affected by different variables (see e.g. what happens by including more South Asian samples to the PCA below), hence the need to draw curved arrows – not necessarily representing a sizable drift; at least not in recent prehistoric admixture events for which we have a reasonable chronological transect.

reich-arrows-admixture-neolithic-bronze-age
Representation of mixture events between European prehistoric peoples in the PCA. Image modified from David Reich‘s Who We Are and How We Got Here (2018).

Ethnolinguistic identification is a risky business that brings back memories of an evil use of cultural history and its consequences (at least in Western Europe, where this tradition was discontinued after WWII), but it seems necessary for those of us who want to find some confirmation of proposed dialectal schemes and language contacts.

Eneolithic Steppe vs. Steppe Maykop

First things first: I tested Bronze Age Eurasian peoples for the only two true steppe populations sampled to date, as potential sources of their “Steppe ancestry” – conventionally described as an EHG:CHG admixture, similar to that found in the first sampled Yamnaya individuals. I used the rightpops of Wang et al. (2018), but with a catch: since authors used WHG as a leftpop and Villabruna as a rightpop, and I find that a little inconsequential*, I preferred the strategy in Ning et al. (2019), contrasting as outgroup Eneolithic_Steppe (ca. 4300 BC) vs. Steppe_Maykop (ca. 3500 BC) when testing for WHG as a source population.

*WHG usually includes samples from a ‘western’ cluster (Loschbour and La Braña) and an ‘eastern’ cluster (Villabruna and Koros), see Lipson et al. (2017). Therefore, it doesn’t make much sense to include the same (or a very similar) population as a source AND an outgroup.

NOTE. For all other qpAdm analyses below, where WHG was not used as leftpop, I have used Villabruna as rightpop following Wang et al. (2019).

greater-caucasus-steppe-ancestry
Map of samples and sites mentioned in Wang et al. (2019), modified from the original to include labels of Eneolithic_Steppe and Steppe_Maykop samples. See PCA and ADMIXTURE grahpic for the identification of specific samples.

Results are not much different from what has been reported. In general, Yamnaya and related groups such as Bell Beakers and Steppe-related Chalcolithic/Bronze Age populations show good fits for Eneolithic_Steppe as their closest source for Steppe ancestry, and bad fits for Steppe_Maykop, whereas Corded Ware groups show the opposite, supporting their known differences.

This trend seems to be tempered in some groups, though, most likely due the influence of Samara_LN-like admixture in Circum-Baltic Late Neolithic and Eastern Corded Ware groups, and the influence of Anatolia_N/EEF-like admixture in Balkan and late European CWC or BBC groups. In fact, the more EEF-related ancestry in a populatoin, the less reliable these generic models (and even specific ones) seem to become when distinguishing the Steppe-related source.

NOTE. For more on this, see the discussion on Circum-Baltic Corded Ware peoples, and the discussion on Mycenaeans and their potential source populations.

These are just broad strokes of what might have happened around the Pontic–Caspian steppes before and during the Early Bronze Age expansions. The most relevant quest right now for Indo-European studies is to ascertain the chain of admixture events that led to the development and expansion of Indo-Uralic and its offshoots, Indo-European and Uralic.

mesolithic-eastern-europe-post-swiderian
Eastern European Mesolithic with the expansion of Post-Swiderian cultures. See full map.

A history of Steppe ancestry

This post is divided in (more or less accurate) chronological developments as follows:

  1. Hunter-gatherer pottery and the steppes
  2. Khvalynsk and Sredni Stog
  3. Post-Stog and Proto-Corded Ware
  4. Yamnaya and Afanasievo

1. Hunter-gatherer pottery and the steppes

I laid out in the ASOSAH book series the general idea – based on attempts to reconstruct the linguistic ancestor of Indo-Uralic – that Eurasiatic speakers might have expanded with the North-Eastern Techno-Complex that spread through north-eastern Europe during the warm period represented by the transition of the Palaeolithic to the Mesolithic.

If one were to trust the traditional migrationist view, a post-Swiderian population expanded from central-eastern Europe (potentially related originally to Epi-Gravettian peoples, represented by WHG ancestry) into north-eastern Europe, and then further east into the Trans-Urals, to then reappear in eastern Europe as a back-migration represented by the spread of hunter-gatherer pottery.

The marked shift from WHG-like towards EHG-related ancestry from Baltic Mesolithic (ca. 30%) to Combed Ware cultures (ca. 65%-100%) supports this continuous westward expansion, that is possibly best represented in the currently available sampling by the ‘south-eastern’ shift (CHG:ANE-related) of the hunter-gatherer from Lebyazhinka IV (5600 BC) relative to the older one from Sidelkino (9300 BC), both from the Samara region in the Middle Volga:

Mesolithic-Neolithic transition ca. 7000-6000 BC, with hunter-gatherer pottery groups spreading westwards. See full map.

From Anthony (2019):

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, 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.

Given the lack of a proper geographical and chronological transect of ancient DNA from eastern European groups, and the discontinuous appearance of both R1b-M73 and R1b-M269 lineages on both sides of the Urals within the WHG:ANE cline, where EHG appears to have formed, it is impossible at this point to assert anything with enough degree of certainty. For simplicity purposes, though, I risked to equate the expansion of R1b-M73 in West Siberia as potentially associated with Micro-Altaic, and the expansion of hg. R1b-M269 with the spread of Indo-Uralic on both sides of the Urals.

NOTE. For incrementally speculative associations of languages with prehistoric cultures and their potential link to ancestry ± haplogroup expansions, you can check sections on Early Indo-Europeans and Uralians, Indo-Uralians, Altaic peoples, Eurasians, or Nostratians. I explained why I made these simplistic choices here.

While this identification of the Indo-Uralic expansion with hg. R1b is more or less straightforward for the Cis-Urals, given the available ancient DNA samples, it will be very difficult (if at all possible) to trace the migration of these originally R1b-M269-rich populations into Trans-Uralian groups that could eventually be linked to Yukaghir speakers. The sheer number of potential admixture events and bottlenecks in Siberian forest, taiga, and tundra regions since the Mesolithic until Yukaghirs were first attested is guaranteed to give more than one headache in upcoming years…

neolithic-steppes-samara-mariupol
Spread of hunter-gatherer pottery in eastern Europe ca. 6000-5000 BC. See full map.

The slight increase in WHG-related ancestry in Ukraine Neolithic groups relative to Mesolithic ones questions the arrival of this eastern influence in the north Pontic area, or at least its relevance in genomic terms, although the cluster formed is similar to the previous one and to Combed Ware groups – despite the Central European and Baltic influences in the north Pontic region – with some samples showing 0% change relative to Mesolithic groups.

ukraine-samara-mesolithic-neolithic-evolution
Structure and change in hunter-gatherer-related populations, from Mathieson et al. (2018). Inferred ancestry proportions for populations modelled as a mixture of WHG, EHG and CHG. Dashed lines show populations from the same geographic region. Percentages indicate proportion of WHG + EHG ancestry. Standard errors range from 1.5 to 8.3%.

NOTE. For more on Indo-Uralic and its reconstruction from a linguistic point of view, check out its dedicated section on ASOSAH, or the recently published (behind paywall) The Precursors of Proto-Indo-European, edited by Kloekhorst and Pronk, Brill (2019). Authors of specific chapters have posted their contributions to Academia.edu, where they can be downloaded for free.

2. Khvalynsk and Sredni Stog

The cluster formed by the three available samples of the Khvalynsk culture (early 5th millennium BC) might be described, as expected from its position in the PCA, as a mixture of EHG-like populations of the Middle Volga with CHG-like ancestry close to that represented by samples from Progress-2 and Vonyuchka, in the North Caucasus Piedmont (ca. 4300 BC):

This variable CHG-like admixture shown in the wide cluster formed by the available Khvalynsk-related samples support the interpretation of a recently created CHG mating network in Anthony (2019):

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.

steppe-ancestry-pca-neolithic-khvalynsk
Detail of the PCA of Eurasian samples, including Neolithic clusters with the hypothesized gene flows related to (1) the formation and (2) expansion of Khvalynsk and the (3) emergence of late Sredni Stog. See full image.

The richest copper assemblage found in all Khvalynsk burials belongs to an individual of hg. R1b-V1636 and intermediate Samara_HG:Eneolithic_Steppe ancestry, while full Eneolithic_Steppe-like admixture in the Middle Volga is represented by the commoner of Khvalynsk II, of hg. Q1. The finding of hg. R1b-V1636 in the North Caucasus Piedmont – and R1b-P297 in the Samara region (probably including Yekaterinovka) begs the question of the origin of hg. R1b-V1636 in the Khvalynsk community. Based on its absence in ancient samples from the forest zone, it is tempting to assign it to steppe hunter-gatherers down the Lower Volga and possibly to the east of it, who infiltrated the Samara region precisely during these population movements described by Anthony (2019).

Suvorovo-related samples from the Balkans, including the Varna and Smyadovo outliers of Steppe ancestry, are closely related to the Khvalynsk expansion:

Similarly, the ancestry of late Sredni Stog samples from Dereivka seem to be directly related to the expansion of Mariupol-like individuals over populations of Suvorovo-Novodanilovka-like admixture, as suggested by the resurgence of typical Ukraine Neolithic haplogroups, the shift in the PCA, and the models of Eneolithic_Steppe vs. Steppe_Maykop above:

#EDIT (11 Nov 2019): In fact, the position of the unpublished Greece_Neolithic outlier that appeared in the Wang et al. (2018) preprint (see full PCA and ADMIXTURE) show that the expanding Suvorovo chiefs from the Balkans formed a tight cluster close to the two published outliers with Steppe ancestry from Bulgaria.

The Ukraine_Neolithic outlier, possibly a Novodanilovka-related sample suggests, based on its position in the PCA close to the late Trypillian outlier of Steppe-related ancestry, that Ukraine_Eneolithic samples from Dereivka are a mixture of Ukraine_Neolithic and a Novodanilovka-like community similar to Suvorovo.

The Trypillian_Eneolithic-like admixture found among Proto-Corded Ware peoples (see below) would then feature potentially a small Steppe_Eneolithic-like component already present in the north Pontic area, too.

pca-suvorovo-novodanilovka-khvalynsk-trypillia-greece-ukraine-neolithic-outlier
Image modified from Wang et al. (2018). Samples projected in PCA of 84 modern-day West Eurasian populations (open symbols). Previously known clusters have been marked and referenced. Marked and labelled are the Balkan samples referenced in this text An EHG and a Caucasus ‘clouds’ have been drawn, leaving Pontic-Caspian steppe and derived groups between them. See the original file here.

Furthermore, whereas Anthony (2019) mentions a long-lasting predominance of hg. R1b in elite graves of the Eneolithic Volga basin, not a single sample of hg. R1a is mentioned supporting the community formed by the Alexandria individual, supposedly belonging to late Sredni Stog groups, but with a Corded Ware-like genetic profile (suggesting yet again that it is possibly a wrongly dated sample).

NOTE. A lack of first-hand information rather than an absence of R1a-M417 samples in the north Pontic forest-steppes would not be surprising, since Anthony is involved in the archaeology of the Middle Volga, but not in that of the north Pontic area.

eneolithic-pontic-caspian-steppe-khvalynsk-novodanilovka-suvorovo
Khvalynsk expansion through the Pontic–Caspian steppes in the early 5th millennium BC. See full map.

3. Post-Stog and Proto-Corded Ware

The origin of the Pre-Corded Ware ancestry is still a mystery, because of the heterogeneity of the sampled groups to date, and because the only ancestral sample that had a compatible genetic profile – I6561 from Alexandria – shows some details that make its radiocarbon date rather unlikely.

The most likely explanation for the closest source population of Corded Ware groups, found in the three core samples of Steppe_Maykop and in Trypillian Eneolithic samples from the first half of the 4th millennium BC, is still that a population of north Pontic forest-steppe hunter-gatherers hijacked this kind of ancestry, that was foreign to the north Pontic region before the Late Eneolithic period, later expanding east and west through the Podolian–Volhynian upland, due to the complex population movements of the Late Eneolithic.

NOTE. The idea of Trypillia influencing the formation of the Steppe_MLBA ancestry proper of Uralic peoples has been around for quite some time already, since the publication of Narasimhan et al. (2018) (see here or here).

steppe-ancestry-pca-corded-ware-bronze-age
Detail of the PCA of Eurasian samples, including Corded Ware groups and related clusters, as well as outliers, with hypothesized gene flows related to the (1) formation and (2) initial expansion of Pre-Corded Ware ancestry, as well as (3) later regional admixture events. See full image.

The specifics of how the Proto-Corded Ware community emerged remain unclear at this point, despite the simplistic description by Rassamakin (1999) of the Late Eneolithic north Pontic population movements as a two-stage migration of 1) late Trypillian groups (Usatovo) west → east, and (2) Late Maykop–Novosvobodnaya east → west. So, for example, Manzura (2016) on the Zhivotilovka “cultural-historical horizon” (emphasis mine):

Indeed, the very complex combination of different cultural traits in the burial sites of the Zhivotilovka type is able to generate certain problems in the search for the origins of this phenomenon. The only really consistent attribute is the burial rite in contracted position on the left or right side. Yu. Rassamakin is correct in asserting that this position of the deceased can be considered as new in the North Pontic region (Rassamakin 1999, 97). However, this opinion can be accepted only partially for the territory between Dniester and Lower Don. This position is well known in the Usatovo culture in the Northwest Pontic region, although skeletons on the right side are evidenced there only in double burials, whereas single burials contain the deceased only in a contracted position on the left side. On the other hand, the southern and western orientation of the deceased, which is one of the main burial traits of the Zhivotilovka type, is not characteristic of the Usatovo culture. Nevertheless, it is possible to suppose that at least part of the Usatovo population could have played a part in the formation of the cultural type under consideration here. One aspect of this cultural tradition, for instance, could be represented by skeletons on the left side and oriented in north-eastern and eastern directions.

Especially close ties can be traced between the Zhivotilovka and Maykop-Novosvobodnaya traditions, as exemplified by similar burial customs and various grave goods. It is beyond any doubt that the Maykop-Novosvobodnaya population was actively involved in the spread of the main Zhivotilovka cultural traits. The influence of North Caucasian traditions can be well observed, at least as far as the Dnieper Basin, but farther west influence is not manifested pronouncedly. The role of cultural units situated between the Dniester and Don rivers in the process of emergence of the Zhivotilovka type looks somewhat vague. Now, it can be quite confidently asserted that at the end of the 4th millennium BC this territory was settled by migrants from the North Caucasus and Carpathian-Dniester region. This event in theory had to stimulate cultural transformations in the Azov-Black Sea steppes and, thus, bearers of local cultural traditions perhaps could have participated in forming the culture under consideration. In any event, the Zhivotilovka type can be regarded as a complex phenomenon that emerged within the regime of intensive cultural dialogue and that it absorbed totally diff erent cultural traditions. The spread of the Zhivotilovka graves across the Pontic steppes from the Carpathians to the Lower Don or even to the Kuban Basin clearly signalizes a rapid dissolution of former cultural borders and the beginning of active movements of people, things and ideas over vast territories.

zhivotilovka-horizon-north-pontic-area

What were the factors or reasons that could have provoked this event? In the beginning of the second half of the 4th millennium BC two advanced cultural centers emerged in the south of Eastern Europe. These were the Maykop-Novosvobodnaya and Usatovo cultures, which in spite of their separation by great distances were structurally very alike. This is expressed in similar monumental burial architecture, complex burial rites, even the composition of grave goods, developed bronze metallurgy, high standards of material culture, etc. Both cultures in a completely formed state exemplify prosperous societies with a high level of economic and social organization, which can correspond to the type of ranked or early complex societies. Normally, the social elite in such polities tends to rigidly control basic domains social, economic and spiritual life using different mechanisms, even open compulsion (Earle 1987, 294-297). To some extent similar social entities can be found at this moment in the forest-steppe zone of the Carpathian-Dniester region, as reflected by the well organized settlement of Brânzeni III and the Vykhatitsy cemetery (Маркевич 1981; Дергачев 1978). In spite of their complex character, such societies represent rather friable structures, which could rapidly disintegrate due to unfavourable inner or external factors.

The societies in question emerged and existed during a time of favourable natural climatic conditions, which is considered to be a transitional period from the Atlantic to the Subboreal period, lasting approximately from 3600 to 3300 cal BC, or a climatic optimum for the steppe zone (Иванова и др. 2011, 108; Спиридонова, Алешинская 1999, 30-31). These conditions to a large degree could guarantee a stable exploitation of basic resources and support existing social hierarchies. However, after 3300 cal BC significant climatic changes occurred, accompanied by an increasing aridization and fall in temperature. This event is usually termed the “Piora oscillation” or “Rapid Climatic Event”, and is regarded as having been of global character (Magny, Haas 2004). These rapid changes could have seriously disturbed existing economic and social relations and finally provoked a similar rapid disintegration of complex social structures. In this case the sites of the Zhivotilovka type could represent mere fragments of former prosperous societies, which under conditions of the absence of centralized social control and stable cultural borders tried to recombine social and economic ties. However, the population possessed the necessary social experience and important technological resources, such as developed stock-breeding based on the breeding of small cattle and wheeled transport, so they were ready for opening new territories in their search for a better life.

maykop-trypillia-intrusion-steppes
Disintegration, migration, and imports of the Azov–Black Sea region. First migration event (solid arrows): Gordineşti–Maikop expansion (groups: I – Bursuchensk; II – Zhyvotylivka; III – Vovchans’k; IV – Crimean; V – Lower Don; VI – pre-Kuban). Second migration event (hollow arrows): Repin expansion. After Rassamakin (1999), Demchenko (2016).

For more on chronology and the potentially larger, longer-lasting Zhivotilovka–Volchansk–Gordineşti cultural horizon and its expansion through the Podolian–Volhynian upland, read e.g. on the Yampil Complex in the latest volume 22 of Baltic-Pontic Studies (2017):

In the forest-steppe zone of the North-West Pontic area, important data concerning the chronological position of the Zhivotilovka-Volchansk group have been produced by the exploration of the Bursuceni kurgan, which is still awaiting full publication [Yarovoy 1978; cf. also Demcenko 2016; Manzura 2016]. Burials linked with the mentioned group were stratigraphically the eldest in the kurgan, and pre-dated a burial in the extended position and [Yamnaya culture] graves. Two of these burials (features 20 and 21) produced radiocarbon dates falling around 3350-3100 BC [Petrenko, Kovaliukh 2003: 108, Tab. 7]. Similar absolute age determinations were obtained for Podolia kurgans at Prydnistryanske [Goslar et al. 2015]. These dates, falling within the Late Eneolithic, mark the currently oldest horizon of kurgan burials in the forest-steppe zone of the North-West Pontic area. The Podolia graves linked with other, older traditions of the steppe Eneolithic seem to represent a slightly later horizon dated to the transition between the Late Eneolithic and Early Bronze Age.

The presence on the left bank of the Dniester River of kurgans associated with the Eneolithic tradition, which at the same time reveals connections with the Gordineşti-Kasperovce-Horodiştea complex, raises questions about the western range of the new trend in funerary rituals, and its potential connection with the expansion of the late Trypilia culture to the West Podolia and West Volhynia Regions. The data potentially suggesting the attribution of kurgans from the upper Dniester basin to this period is patchy and difficult to verify [e.g. Liczkowce – see Sulimirski 1968: 173]. In this context, the discovery of vessels in the Gordineşti style in a kurgan at Zawisznia near Sokal is inspiring [Antoniewicz 1925].

zhivotilovka-volchansk-burial-podolia
Burials representing funerary traditions of Zhivotilovka-Volchansk group in Podolie kurgans: 1 – Porohy, grave 3A/7, 2 – Kuzmin, grave 2/2 [after Klochko et al. 2015b, Bubulich, Khakhey 2001]

Another interesting aspect of potential source populations, in combination with those above for Eneolithic_Steppe vs. Steppe_Maykop, are groups with worse fits for Steppe_Maykop_core, which include Potapovka and Srubnaya, as reported by Wang et al. (2018), but also Sintastha_MLBA (although not Andronovo). This is compatible with the long-term admixture of Abashevo chiefs dominating over a majority of Poltavka-like herders in the Don-Volga-Ural steppes during the formation of the Sintashta-Potapovka-Filatovka community, also visible in the typical Yamnaya lineages and Yamnaya-like ancestry still appearing in the region centuries after the change in power structures had occurred.

NOTE. If you feel tempted to test for mixtures of Khvalynsk_EN, Eneolithic_Steppe, Yamnaya, etc. as a source population for Corded Ware, go for it, but it’s almost certain to give similar ‘good’ fits – whatever the model – in some Corded Ware groups and not in others. It is still unclear, as far as I know, how to formally distinguish a mixture of Corded Ware-related from a Yamnaya-related source in the same model, and the results obtained with a combination of Steppe_Maykop-related + Eneolithic_Steppe-related sources will probably artificially select either one or the other source, as it probably happened in Ning et al. (2019) with Proto-Tocharian samples (see qpAdm values) that most likely had a contribution of both, based on their known intense interactions in the Tarim Basin.

eneolithic-pontic-caspian-steppes-east-europe
Expansion of north Pontic cultures and related groups during the Late Eneolithic. See full map.

4. Yamnaya and Afanasievo

I don’t think it makes much sense to test for GAC (or Iberia_CA, for that matter) as Wang et al. (2019) did, given the implausibility of them taking part in the formation of late Repin during the mid-4th millennium BC around the Don-Volga interfluve (represented by its offshoots Yamnaya and Afanasievo), whether these or other EEF-related populations show ‘better’ fits or not. Therefore, I only tested for more or less straightforward potential source populations:

steppe-ancestry-pca-yamnaya-hungary-bulgaria-vucedol
Detail of the PCA of Eurasian samples, including Yamnaya groups and related clusters, as well as outliers, with hypothesized gene flows related to its (1) formation and (2) expansion. Also included is the inferred position of the admixed sample Yamnaya_Hungary_EBA1. See full image.

Quite unexpectedly – for me, at least – it appears that Afanasievo and Yamnaya invariably prefer Khvalynsk_EN as the closest source rather than a combination including Eneolithic_Steppe directly. In other words, late Repin shows largely genetic continuity with the Steppe ancestry already shown by the three sampled individuals from the Khvalynsk II cemetery, in line with the known strong bottlenecks of Khvalynsk-related groups under R1b lineages, visible also later in Afanasievo and Yamnaya and derived Indo-European-speaking groups under R1b-L23 subclades.

NOTE. This explains better the reported bad fits of models using directly Eneolithic_Steppe instead of Khvalynsk_EN for Afanasievo and Yamnaya Kalmykia, as is readily evident from the results above, instead of a rejection of an additional contribution to an Eneolithic_Steppe-like population, as I interpreted it, based on Anthony (2019).

repin-zhivotilovka-north-pontic-steppe
Map of major sites of the Zhivotilovka-Volchansk group (A) and Repin culture (B), by Rassamakin (see 1994 and 2013). (A) 1 – Primorskoye; 2 – Vasilevka; 3 – Aleksandrovka; 4 – Boguslav; 5 – Pavlograd; 6 – Zhivotilovka; 7 – Podgorodnoye; 8 – Novomoskovsk; 9- Sokolovo; 10 – Dneprelstan; 11- Razumovka; 12 – Pologi; 13 – Vinogradnoye; 14 – Novo-Filipovka; 15 – Volchansk; 16 – Yuryevka; 17 – Davydovka; 18 – Novovorontsovka; 19 – Ust-Kamenka; 20 – Staroselye; 21- Velikaya Aleksandrovka; 22- Kovalevka; 23 – Tiraspol; 24 – Cura-Bykuluy; 25 – Roshkany; 26 – Tarakliya; 27 – Kazakliya; 28 – Bolgrad; 29 – Sarateny; 30 – Bursucheny; 31 – Novye Duruitory; 232 – Kosteshty. (B) 1 – Podgorovka; 2 – Aleksandria; 3 – Volonterovka; 4 – Zamozhnoye; 5 – Kremenevka; 6 – Ogorodnoye; 7 – Boguslav; 8 – Aleksandrovka; 9 – Verkhnaya Mayevka; 10 – Duma Skela; 11 – Zamozhnoye; 12 – Mikhailovka II.

This might suggest that the Steppe ancestry visible in samples from Progress-2 and Vonyuchka, sharing the same cluster with the Khvalynsk II cemetery commoner of hg. Q1, most likely represents North Caspian or Black Sea–Caspian steppe hunter-gatherer ancestry that increased as Khvalynsk settlers expanded to the south-west towards the Greater Caucasus, probably through female exogamy. That would mean that Steppe_Maykop potentially represents the ‘original’ ancestry of steppe hunter-gatherers of the North Caucasus steppes, which is also weakly supported by the available similar admixture of the Lola culture. The chronology, geographical location and admixture of both clusters seemed to indicate the opposite.

eneolithic-steppe-maykop-ehg-chg-ag2
Modelling results for the Steppe and Caucasus cluster. Additional ‘eastern’ AG-Siberian gene flow in Steppe Maykop relative to Eneolithic Steppe. From Wang et al. (2019).

Due to the limitations of the currently available sampling and statistical tools, and barring the dubious Alexandria outlier, it is unclear how much of the late Trypillian-related admixture of late Repin (as reflected in Yamnaya and Afanasievo) corresponds to late Trypillian, Post-Stog, or Proto-Corded Ware groups from the north Pontic area. A mutual exchange suggestive of a common mating network (also supported by the mixed results obtained when including Khvalynsk_EN as source for early Corded Ware groups) seem to be the strongest proof to date of the Late Proto-Indo-European – Uralic contacts reflected in the period when post-laryngeal vocabulary was borrowed (with some samples predating the merged laryngeal loss), before the period of intense borrowing from Pre- and Proto-Indo-Iranian.

Between-group differences of Yamnaya samples are caused – like those between Corded Ware groups – by the admixture of a rapidly expanding society through exogamy with regional populations, evidenced by the inconstant affinities of western or southern outliers for previous local populations of the west Pontic or Caucasus area. This explanation for the gradual increase in local admixture is also supported by the strong, long-term patrilineal system and female exogamy practiced among expanding Proto-Indo-Europeans.

chalcolithic-early-bronze-yamnaya-corded-ware-vucedol
Groups of the Yamnaya culture and its western expansion after ca. 3100 BC, and Corded Ware after ca. 2900 BC See full map.

Bell Beakers and Mycenaeans

This Eneolithic_Steppe ancestry is also found among Bell Beaker groups (see above). More specifically, all Bell Beaker groups prefer a source closest to a combination of Yamnaya from the Don and Baden LCA individuals from Hungary, rather than with Corded Ware and GAC, despite the quite likely admixture of western Yamnaya settlers with (1) south-eastern European (west Pontic, Balkan) Chalcolithic populations during their expansion through the Lower Danube and with (2) late Corded Ware groups (already admixed with GAC-like populations) during their expansion as East Bell Beakers:

Similarly, Mycenaeans show good fits for a source close to the Yamnaya outlier from Bulgaria:

steppe-ancestry-pca-bell-beakers-mycenaeans
Detail of the PCA of Eurasian samples, including Bell Beaker and Balkan EBA groups and related clusters, as well as outliers, including ancestral Yamnaya samples from Hungary (position inferred) and Bulgaria. Also marked are Minoans, Mycenaeans and Armenian BA samples. See full image.

You can read more on Yamnaya-related admixture of Bell Beakers and Mycenaeans, and on Afanasievo-related admixture of Iron Age Proto-Tocharians.

Conclusion

The use of the concept of “Yamnaya ancestry”, then “Steppe ancestry” (and now even “Yamnaya Steppe ancestry“?) has already permeated the ongoing research of all labs working with human population genomics. Somehow, the conventional use of Yamnaya_Samara samples opposed to a combination of other ancient samples – alternatively selected among WHG, EHG, CHG/Iran_N, Anatolia_N, or ANE – has spread and is now unquestionably accepted as one of the “three quite distinct” ancestral groups that admixed to form the ancestry of modern Europeans, which is a rather odd, simplistic and anachronistic description of prehistory…

It has now become evident that authors involved with the Proto-Indo-European homeland question – and the tightly intertwined one of the Proto-Uralic homeland – are going to dedicate a great part of the discussion of many future papers to correct or outright reject the conclusions of previous publications, instead of simply going forward with new data.

The most striking argument to mistrust the current use of “Steppe ancestry” (as an alternative name for Yamnaya_Samara, and not as ancestry proper of steppe hunter-gatherers) is not the apparent difference in direct Eneolithic sources of Steppe ancestry for Corded Ware and Yamnaya-related peoples – closer to the available samples classified as Steppe_Maykop and Eneolithic_Steppe, respectively – or their different evolution under marked Y-DNA bottlenecks.

It is not even the lack of information about the distant origin of these Pontic–Caspian steppe hunter-gatherers of the 5th and 4th millennium BC, with their shared ancestral component potentially separated during the warmer Palaeolithic-Mesolithic transition, when the steppes were settled, without necessarily sharing any meaningful recent history before the formation of the Proto-Indo-Uralic community.

NOTE. I have raised this question multiple times since 2017 (see e.g. here or here).

The most striking paradox about simplistically misinterpreting “Steppe ancestry” as representative of Indo-European expansions is that those sub-Neolithic Pontic–Caspian steppe hunter-gatherers that had this ancestry in the 6th millennium BC were probably non-Indo-European-speaking communities, most likely related to the North(West) Caucasian language family, based on the substrate of Indo-Anatolian that sets it apart from Uralic within the Indo-Uralic trunk, and on later contacts of Indo-Tocharian with North-West Caucasian and Kartvelian, the former probably represented by Maykop and its contact with the Repin and early Yamnaya cultures.

NOTE. For more on this, see Allan Bomhard’s recent paper on the Caucasian substrate hypothesis and its ongoing supplement Additional Proto-Indo-European/Northwest Caucasian Lexical Parallels.

steppe-ancestry-racimo
“Spatiotemporal kriging of YAM steppe ancestry during the Holocene, using 5000 spatial grid points. The colors represent the predicted ancestry proportion at each point in the grid.” Image with evolution from ca. 2800 BC until the present day, modified from Racimo et al. (2019). The Copenhagen group considers the expansion of this component as representative of expanding Indo-Europeans…

This kind of error happens because we all – hence also authors, peer reviewers, and especially journal editors – love far-fetched conclusions and sensational titles, forgetting what a paper actually shows and – always more importantly in scientific reports – what it doesn’t show. This is particularly true when more than one field is involved and when extraordinary claims involve aspects foreign to the journal’s (and usually the own authors’) main interests. One would have thought that the glottochronological fiasco published in Science in 2012 (open access in PMC) should have taught an important lesson to everyone involved. It didn’t, because apparently no one has felt the responsibility or the shame to retract that paper yet, even in the age of population genomics.

If anything, the excesses of mathematical linguistics – using computational methods to try and reconstruct phylogenetic trees – have perpetuated a form of misunderstood Scientism which blindly relies on a simple promise made by authors in the Materials and Method section (rarely if ever kept beyond it) to use statistics rather than resorting to the harder, well-informed, comprehensive reasoning that is needed in the comparative method. After all, why should anyone invest hundreds of hours (or simply show an interest in) learning about historical linguistics, about ancient Indo-European or Uralic languages, carefully argumenting and discussing each and every detail of the reconstruction, when one can simply rely on the own guts to decide what is Science and what isn’t? When one can trust a promise that formulas have been used?

The conservative, null hypothesis when studying prehistoric Eurasian samples related to evolving cultures was universally understood as no migration, or “pots not people” (as most western archaeologists chose to believe until recently), whereas the alternative one should have been that there were in fact migration events, some of them potentially related to the expansion of Eurasian languages ancestral to the historically attested ones. Beyond this migrationist view there were obviously dozens of thorough theories concerning potential linguistic expansions associated with specific prehistoric cultures, and a myriad of less developed alternatives, all of which deserved to be evaluated after the null hypothesis had been rejected.

Despite the shortcomings of the 2015 papers and their lack of testing or discussion of different language expansion models, the spread of the so-called “Yamnaya ancestry” – an admixture especially prevalent (after the demise of the Yamnaya) among the most likely ancient Uralic-speaking groups as well as among modern Uralic speakers and recently acculturated groups from Eastern Europe – has been nevertheless invariably concluded by each lab to support the theories of their leading archaeologist, often combined with pre-aDNA theories of geneticists based on modern haplogroup distributions. This is as evident a case of confirmation bias, circular reasoning, and jumping to conclusions as it gets.

Why many researchers of other labs have chosen to follow such conclusions instead of challenging or simply ignoring them is difficult to understand.

Related

Yamnaya ancestry: mapping the Proto-Indo-European expansions

steppe-ancestry-expansion-europe

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

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

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

Sections:

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

1. Neolithic

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

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

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

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

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

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

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

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

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

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

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

2. Eneolithic

From Anthony (2019):

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

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

From Wang et al (2019):

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

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

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

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

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

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

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

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

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

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

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

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

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

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

3. Early Bronze Age

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

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

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

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

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

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

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

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

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

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

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

4. Middle to Late Bronze Age

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

4.1. Bell Beakers

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

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

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

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

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

olalde-iberia-chalcolithic

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

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

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

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

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

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

4.2. Palaeo-Balkan

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

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

4.3. Sintashta-Potapovka-Filatovka

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

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

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

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

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

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

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

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

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

4.4. Afanasevo

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

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

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

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

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

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

From Damgaard et al. Science (2018):

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

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

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

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

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

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

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

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

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

Related

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

ekaterinovsky-cape

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

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

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

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

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

More specifically:

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

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

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

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

Important sites mentioned in both papers and in this text:

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

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

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

The Khvalynsk chieftain

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

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

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

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

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

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

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

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

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

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

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

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

On SNP calls

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

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

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

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

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

steppe-forest-steppe-biomes

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

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

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

A Persistent ecological and cultural frontier

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

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

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

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

A barrier to steppe migrations into northern Europe

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

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

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

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

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

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

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

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

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

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

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

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

Related

R1a-Z280 lineages in Srubna; and first Palaeo-Balkan R1b-Z2103?

herodotus-world-map

Scythian samples from the North Pontic area are far more complex than what could be seen at first glance. From the new Y-SNP calls we have now thanks to the publications at Molgen (see the spreadsheet) and in Anthrogenica threads, I think this is the basis to work with:

NOTE. I understand that writing a paper requires a lot of work, and probably statistical methods are the main interest of authors, editors, and reviewers. But it is difficult to comprehend how any user of open source tools can instantly offer a more complex assessment of the samples’ Y-SNP calls than professionals working on these samples for months. I think that, by now, it should be clear to everyone that Y-DNA is often as important (sometimes even more) than statistical tools to infer certain population movements, since admixture can change within few generations of male-biased migrations, whereas haplogroups can’t…

Srubna

Srubna-Andronovo samples are as homogeneous as they always were, dominated by R1a-Z645 subclades and CWC-related (steppe_MLBA) ancestry.

The appearance of one (possibly two) R-Z280 lineages in this mixed Srubna-Alakul region of the southern Urals and this early (1880-1690 BC, hence rather Pokrovka-Alakul) points to the admixture of R1a-Z93 and R1a-Z280 already in Abashevo, which also explains the wide distribution of both subclades in the forest zones of Central Asia.

If Abashevo is the cornerstone of the Indo-Iranian / Uralic community, as it seems, the genetic admixture would initially be quite similar, undergoing in the steppes a reduction to haplogroup R1a-Z93 (obviously not complete), at the same time as it expanded to the west with Pokrovka and Srubna, and to the east with Petrovka and Andronovo. To the north, similar reductions will probably be seen following the Seima-Turbino phenomenon.

NOTE. Another R1a-Z280 has been found in the recent sample from Bronze Age Poland (see spreadsheet). As it appears right now in ancient and modern DNA, there seems to be a different distribution between subclades:

  • R1a-Z280 (formed ca. 2900 BC, TMRCA ca. 2600 BC) appears mainly distributed today to the east, in the forest and steppe regions, with the most ‘successful’ expansions possibly related to the spread of Abashevo- and Battle Axe-related cultures (Indo-Iranian and Uralic alike).
  • R1a-M458 (formed ca. 2700, TMRCA ca. 2700 BC) appears mainly distributed to the north, from central Europe to the east – but not in the steppe in aDNA, with the most ‘successful’ expansions to the west.

M458 lineages seem thus to have expanded in the steppe in sizeable numbers only after the Iranian expansions (see a map of modern R1a distributions) i.e. possibly with the expansion of Slavs, which supports the model whereby cultures from central-east Europe (like Trzciniec and Lusatian), accompanied mainly by M458 lineages, were responsible for the expansion of Proto-Balto-Slavic (and later Proto-Slavic).

The finding of haplogroup R1a-Z93, among them one Z2123, is no surprise at this point after other similar Srubna samples. As I said, the early Srubna expansion is most likely responsible for the Szólád Bronze Age sample (ca. 2100-1700 BC), and for the Balkans BA sample (ca. 1750-1625 BC) from Merichleri, due to incursions along the central-east European steppe.

cheek-pieces
Map of decorated bone/antler bridle cheek-pieces and whip handle equivalents. They are often local translations that remained faithful to the originals (from data in Piggott, 1965; Kristiansen & Larsson, 2005; David, 2007). Image from Vandkilde (2014).

Cimmerians

Cimmerian samples from the west show signs of continuity with R1a-Z93 lineages. Nevertheless, the sample of haplogroup Q1a-Y558, together with the ‘Pre-Scythian’ sample of haplogroup N (of the Mezőcsát Culture) in Hungary ca. 980-830 BC, as well as their PCA, seem to depict an origin of these Pre-Scythian peoples in populations related to the eastern Central Asian steppes, too.

NOTE. I will write more on different movements (unrelated to Uralic expansions) from Central and East Asia to the west accompanied by Siberian ancestry and haplogroup N with the post of Ugric-Samoyedic expansions.

Scythians

The Scythian of Z2123 lineage ca. 375-203 BC from the Volga (in Mathieson et al. 2015), together with the sample scy193 from Glinoe (probably also R1a-Z2123), without a date, as well as their common Steppe_MLBA cluster, suggest that Scythians, too, were at first probably quite homogeneous as is common among pastoralist nomads, and came thus from the Central Asian steppes.

The reduction in haplogroup variability among East Iranian peoples seems supported by the three new Late Sarmatian samples of haplogroup R1a-Z2124.

Approximate location of Glinoe and Glinoe Sad (with Starosilya to the south, in Ukrainian territory):

This initial expansion of Scythians does not mean that one can dismiss the western samples as non-Scythians, though, because ‘Scythian’ is a cultural attribution, based on materials. Confirming the diversity among western Scythians, a session at the recent ISBA 8:

Genetic continuity in the western Eurasian Steppe broken not due to Scythian dominance, but rather at the transition to the Chernyakhov culture (Ostrogoths), by Järve et al.

The long-held archaeological view sees the Early Iron Age nomadic Scythians expanding west from their Altai region homeland across the Eurasian Steppe until they reached the Ponto-Caspian region north of the Black and Caspian Seas by around 2,900 BP. However, the migration theory has not found support from ancient DNA evidence, and it is still unclear how much of the Scythian dominance in the Eurasian Steppe was due to movements of people and how much reflected cultural diffusion and elite dominance. We present new whole-genome results of 31 ancient Western and Eastern Scythians as well as samples pre- and postdating them that allow us to set the Scythians in a temporal context by comparing the Western Scythians to samples before and after within the Ponto-Caspian region. We detect no significant contribution of the Scythians to the Early Iron Age Ponto-Caspian gene pool, inferring instead a genetic continuity in the western Eurasian Steppe that persisted from at least 4,800–4,400 cal BP to 2,700–2,100 cal BP (based on our radiocarbon dated samples), i.e. from the Yamnaya through the Scythian period.

(…) Our results (…) support the hypothesis that the Scythian dominance was cultural rather than achieved through population replacement.

Detail of the slide with admixture of Scythian groups in Ukraine:

scythians-admixture

The findings of those 31 samples seem to support what Krzewińska et al. (2018) found in a tiny region of Moldavia-south-western Ukraine (Glinoi, Glinoi Sad, and Starosilya).

The question, then, is as follows: if Scythian dominance was “cultural rather than achieved through population replacement”…Where are the R1b-Z2103 from? One possibility, as I said in the previous post, is that they represent pockets of Iranian R1b lineages in the steppes descended from eastern Yamna, given that this haplogroup appears in modern populations from a wide region surrounding the steppes.

The other possibility, which is what some have proposed since the publication of the paper, is that they are related to Thracians, and thus to Palaeo-Balkan populations. About the previously published Thracian individuals in Sikora et al. (2014):

thracian-samples
Geographic origin of ancient samples and ADMIXTURE results. (A) Map of Europe indicating the discovery sites for each of the ancient samples used in this study. (B) Ancestral population clusters inferred using ADMIXTURE on the HGDP dataset, for k = 6 ancestral clusters. The width of the bars of the ancient samples was increased to aid visualization. https://doi.org/10.1371/journal.pgen.1004353.g001

For the Thracian individuals from Bulgaria, no clear pattern emerges. While P192-1 still shows the highest proportion of Sardinian ancestry, K8 more resembles the HG individuals, with a high fraction of Russian ancestry.

Despite their different geographic origins, both the Swedish farmer gok4 and the Thracian P192-1 closely resemble the Iceman in their relationship with Sardinians, making it unlikely that all three individuals were recent migrants from Sardinia. Furthermore, P192-1 is an Iron Age individual from well after the arrival of the first farmers in Southeastern Europe (more than 2,000 years after the Iceman and gok4), perhaps indicating genetic continuity with the early farmers in this region. The only non-HG individual not following this pattern is K8 from Bulgaria. Interestingly, this individual was excavated from an aristocratic inhumation burial containing rich grave goods, indicating a high social standing, as opposed to the other individual, who was found in a pit.

pca-thracians

The following are excerpts from A Companion to Ancient Thrace (2015), by Valeva, Nankov, and Graninger (emphasis mine):

Thracian settlements from the 6th c. BC on:

(…) urban centers were established in northeastern Thrace, whose development was linked to the growth of road and communication networks along with related economic and distributive functions. The early establishment of markets/emporia along the Danube took place toward the middle of the first millennium BCE (Irimia 2006, 250–253; Stoyanov in press). The abundant data for intensive trade discovered at the Getic village in Satu Nou on the right bank of the Danube provides another example of an emporion that developed along the main artery of communication toward the interior of Thrace (Conovici 2000, 75–76).

Undoubtedly the most prominent manifestation of centralization processes and stratification in the settlement system of Thrace arrives with the emergence of political capitals – the leading urban centers of various Thracian political formations.

getic-thracian
Image from Volf at Vol_Vlad LiveJournal.

Their relationships with Scythians and Greeks

The Scythian presence south of the Danube must be balanced with a Thracian presence north of the river. We have observed Getae there in Alexander’s day, settled and raising grain. For Strabo the coastlands from the Danube delta north as far as the river and Greek city of Tyras were the Desert of the Getae (7.3.14), notable for its poverty and tracklessness beyond the great river. He seems to suggest also that it was here that Lysimachus was taken alive by Dromichaetes, king of the Getae, whose famous homily on poverty and imperialism only makes sense on the steppe beyond the river (7.3.8; cf. Diod. 21.12; further on Getic possessions above the Danube, Paus. 1.9 with Delev 2000, 393, who seems rather too skeptical; on poverty, cf. Ballesteros Pastor 2003). This was the kind of discourse more familiarly found among Scythians, proud and blunt in the strength of their poverty. However, as Herodotus makes clear, simple pastoralism was not the whole story as one advanced round into Scythia. For he observes the agriculture practiced north and west of Olbia. These were the lands of the Alizones and the people he calls the Scythian Ploughmen, not least to distinguish them from the Royal Scythians east of Olbia, in whose outlook, he says, these agriculturalist Scythians were their inferiors, their slaves (Hdt. 4.20). The key point here is that, as we began to see with the Getan grain-fields of Alexander’s day, there was scope for Thracian agriculturalists to maintain their lifestyles if they moved north of the Danube, the steppe notwithstanding. It is true that it is movement in the other direction that tends to catch the eye, but there are indications in the literary tradition and, especially, in the archaeological record that there was also significant movement northward from Thrace across the Danube and the Desert of the Getae beyond it.

Greek literary sources were not much concerned with Thracian migration into Scythia, but we should observe the occasional indications of that process in very different texts and contexts. At the level of myth, it is to be remembered that Amazons were regularly considered to be of Thracian ethnicity from Archaic times onward and so are often depicted in Thracian dress in Greek art (Bothmer 1957; cf. Sparkes 1997): while they are most familiar on the south coast of the Black Sea, east of Sinope, they were also located on the north coast, especially east of the Don (the ancient Tanais). Herodotus reports an origin-story of the Sauromatians there, according to which this people had been created by the union of some Scythian warriors with Amazons captured on the south coast and then washed up on the coast of Scythia (4.110). While the story is unhistorical, it is not without importance. First, it reminds us that passage north from the Danube was not the only way that Thracians, Thracian influence, and Thracian culture might find their way into Scythia. There were many more and less circuitous routes, especially by sea, that could bring Thrace into Scythia. Secondly, the myth offered some ideological basis for the Sauromatian settlement in Thrace that Strabo records, for Sauromatians might claim a Thracian origin through their Amazon forebears. Finally, rather as we saw that Heracles could bring together some of the peoples of the region, we should also observe that Ares, whose earthly home was located in Thrace by a strong Greek and Roman tradition, seems also to have been a deity of special significance and special cult among the Scythians. So much was appropriate, especially from a Classical perspective, in associations between these two peoples, whose fame resided especially in their capacity for war.

skythen
Scythians: cultures and findings (ca. 7th-4th/3rd c. BC). Greek colonies marked with concentric circles.

This broad picture of cultural contact, interaction, and osmosis, beyond simple conflict, provides the context for a range of archaeological discoveries, which – if examined separately – may seem to offer no more than a scatter of peculiarities. Here we must acknowledge especially the pioneering work of Melyukova, who has done most to develop thinking on Thracian–Scythian interaction. As she pointed out, we have a good example of Thracian–Scythian osmosis as early as the mid-seventh century bce at Tsarev Brod in northeastern Bulgaria, where a warrior’s burial combines elements of Scythian and Thracian culture (Melyukova 1965). For, while the manner of his burial and many of the grave goods find parallels in Scythia and not Thrace, there are also goods which would be odd in a Scythian burial and more at home in a Thracian one of this period (notably a Hallstatt vessel, an iron knife, and a gold diadem). Also interesting in this regard are several stone figures found in the Dobrudja which resemble very closely figures of this kind (baby) known from Scythia (Melyukova 1965, 37–38). They range in date from perhaps the sixth to the third centuries bce, and presumably were used there – as in Scythia – to mark the burials of leading Scythians deposited in the area. Is this cultural osmosis? We should probably expect osmosis to occur in tandem with the movement of artefacts, so that only good contexts can really answer such questions from case to case. However, the broad pattern is indicated by a range of factors. Particularly notable in this regard is the observable development of a Thraco-Scythian form of what is more familiar as “Scythian animal style,” a term which – it must be understood – already embraces a range of types as we examine the different examples of the style across the great expanse from Siberia to the western Ukraine. As Melyukova observes, Thrace shows both items made in this style among Scythians and, more numerous and more interesting, a Thracian tendency to adapt that style to local tastes, with observable regional distinctions within Thrace itself. Among the Getae and Odrysians the adaptation seems to have been at its height from the later fifth century to the mid-third century (Melyukova 1965, 38; 1979).

The absence of local animal style in Bulgaria before the fifth century bce confirms that we have cultural influences and osmosis at work here, though that is not to say that Scythian tradition somehow dominated its Thracian counterpart, as has been claimed (pace Melyukova 1965, 39; contrast Kitov 1980 and 1984). Of particular interest here is the horse-gear (forehead-covers, cheek-pieces, bridle fittings, and so on) which is found extensively in Romania and Bulgaria as well as in Scythia, both in hoarded deposits and in burials. This exemplifies the development of a regional animal style, not least in silver and bronze, which problematizes the whole issue of the place(s) of its production. Accordingly, the regular designation as “Thracian” of horse-gear from the rich fourth century Scythian burial of Oguz in the Ukraine becomes at least awkward and questionable (further, Fialko 1995). And let us be clear that this is no minor matter, nor even part of a broader debate about the shared development of toreutics among Thracians and Scythians (e.g., Kitov 1980 and 1984). A finely equipped horse of fine quality was a strong statement and striking display of wealth and the power it implied

(…) while Thracian pottery appears at Olbia, Scythian pottery among Thracians is largely confined to the eastern limits of what should probably be regarded as Getic territory, namely the area close to the west of the Dniester, from the sixth century bce. Rather exceptional then is the Scythian pottery noted at Istros, which has been explained as a consequence of the Scythian pursuit of the withdrawing army of Darius and, possibly, a continued Scythian grip on the southern Danube in its aftermath (Melyukova 1965, 34). The archaeology seems to show us, therefore, that the elite Thracians and Scythians were more open to adaptation and acculturation than were their lesser brethren.

palaeo-balkan-languages
Paleo-Balkan languages in Eastern Europe between 5th and 1st century BC. From Wikipedia.

Conclusion

(…) we see distinct peoples and organizations, for example as Sitalces’ forces line up against the Scythians. Much more striking, however, against that general background, are the various ways in which the two peoples and their elites are seen to interact, connect, and share a cultural interface. We see also in Scyles’ story how the Greek cities on the coast of Thrace and Scythia played a significant role in the workings of relationships between the two peoples. It is not simply that these cities straddled the Danube, but also that they could collaborate – witness the honors for Autocles, ca. 300 bce (SEG 49.1051; Ochotnikov 2006) – and were implicated with the interactions of the much greater non-Greek powers around them. At the same time, we have seen the limited reality of familiar distinctions between settled Thracians and nomadic Scythians and the limited role of the Danube too in dividing Thrace and Scythia. The interactions of the two were not simply matters of dynastic politics and the occasional shared taste for artefacts like horse-gear, but were more profoundly rooted in the economic matrix across the region, so that “Scythian” nomadism might flourish in the Dobrudja and “Thracian-style” agriculture and settlement can be traced from Thrace across the Danube as far as Olbia. All of that offers scant justification for the Greek tendency to run together Thracians and Scythians as much the same phenomenon, not least as irrational, ferocious, and rather vulgar barbarians (e.g., Plato, Rep. 435b), because such notions were the result of ignorance and chauvinism. However, Herodotus did not share those faults to any degree, so that we may take his ready movement from Scythians to Thracians to be an indication of the importance of interaction between the two peoples whom he had encountered not only as slaves in the Aegean world, but as powerful forces in their own lands (e.g., Hdt. 4.74, where Thracian usage is suddenly brought into his account of Scythian hemp). Similarly, Thucydides, who quite without need breaks off his disquisition on the Odrysians to remark upon political disunity among the Scythians (Thuc. 2.97, a favorite theme: cf. Hdt. 4.81; Xen., Cyr. 1.1.4). As we have seen throughout this discussion, there were many reasons why Thracians might turn the thoughts of serious writers to Scythians and vice versa.

It seems, following Sikora et al. (2014), that Thracian ‘common’ populations would have more Anatolian Neolithic ancestry compared to more ‘steppe-like’ samples. But there were important differences even between the two nearby samples published from Bulgaria, which may account for the close interaction between Scythians and Thracians we see in Krzewińska et al. (2018), potentially reflected in the differences between the Central, Southern and the South-Central clusters (possibly related to different periods rather than peoples??).

If these R1b-Z2103 were descended from Thracian elites, this would be the first proof of Palaeo-Balkan populations showing mainly R1b-Z2103, as I expect. Their appearance together with haplogroup I2a2a1b1 (also found in Ukraine Neolithic and in the Yamna outlier from Bulgaria) seem to support this regional continuity, and thus a long-lasting cultural and ethnic border roughly around the Danube, similar to the one found in the northern Caucasus.

However, since these samples are some 2,500 years younger than the Yamna expansion to the south, and they are archaeologically Scythians, it is impossible to say. In any case, it would seem that the main expansion of R1a-Z645 lineages to the south of the Danube – and therefore those found among modern Greeks – was mediated by the Slavic expansions centuries later.

krzewinska-scythians-pca
Modified image from Krzewińska et al. (2018), with added Y-DNA haplogroups to each defined Scythian cluster and Sarmatians. Principal component analysis (PCA) plot visualizing 35 Bronze Age and Iron Age individuals presented in this study and in published ancient individuals in relation to modern reference panel from the Human Origins data set. See image with population references.

On the Northern cluster there is a sample of haplogroup R1b-P312 which, given its position on the PCA (apparently even more ‘modern Celtic’-like than the Hallstatt_Bylany sample from Damgaard et al. 2018), it seems that it could be the product of the previous eastward Hallstatt expansion…although potentially also from a recent one?:

Especially important in the archaeology of this interior is the large settlement at Nemirov in the wooded steppe of the western Ukraine, where there has been considerable excavation. This settlement’s origins evidently owe nothing significant to Greek influence, though the early east Greek pottery there (from ca. 650 bce onward: Vakhtina 2007) and what seems to be a Greek graffito hint at its connections with the Greeks of the coast, especially at Olbia, which lay at the estuary of the River Bug on whose middle course the site was located (Braund 2008). The main interest of the site for the present discussion, however, is its demonstrable participation in the broader Hallstatt culture to its west and south (especially Smirnova 2001). Once we consider Nemirov and the forest steppe in connection with Olbia and the other locations across the forest steppe and coastal zone, together with the less obvious movements across the steppe itself, we have a large picture of multiple connectivities in which Thrace bulks large.

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

While the above description of clear-cut R1a-Steppe and R1b-Balkans is attractive (and probably more reliable than admixture found in scattered samples of unclear dates), the true ancient genetic picture is more complicated than that:

  • There is nothing in the material culture of the published western Scythians to distinguish the supposed Thracian elites.
  • We have the sample I0575, an Early Sarmatian from the southern Urals (one of the few available) of haplogroup R1b-Z2106, which supports the presence of R1b-Z2103 lineages among Eastern Iranian-speaking peoples.
  • We also have DA30, a Sarmatian of I2b lineage from the central steppes in Kazakhstan (ca. 47 BC – 24 AD).
  • Other Sarmatian samples of haplogroup R remain undefined.
  • There is R1a-Z93 in a late Sarmatian-Hun sample, which complicates the picture of late pastoralist nomads further.

Therefore, the possibility of hidden pockets of Iranian peoples of R1b-Z2103 (maybe also R1b-P312) lineages remains the best explanation, and should not be discarded simply because of the prevalent haplogroups among modern populations, or because of the different clusters found, or else we risk an obvious circular reasoning: “this sample is not (autosomically or in prevalent haplogroups) like those we already had from the steppe, ergo it is not from this or that steppe culture.” Hopefully, the upcoming paper by Järve et al. will help develop a clearer genetic transect of Iranian populations from the steppes.

All in all, the diversity among western Scythians represents probably one of the earliest difficult cases of acculturation to be studied with ancient DNA (obviously not the only one), since Scythians combine unclear archaeological data with limited and conflicting proto-historical accounts (also difficult to contrast with the wide confidence intervals of radiocarbon dates) with different evolving clusters and haplogroups – especially in border regions with strong and continued interactions of cultures and peoples.

With emerging complex cases like these during the Iron Age, I am happy to see that at least earlier expansions show clearer Y-DNA bottlenecks, or else genetics would only add more data to argue about potential cultural diffusion events, instead of solving questions about proto-language expansions once and for all…

Related

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

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

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

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

scythian-cimmerian-sarmatian-y-dna-mtdna

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

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

    About the PCA

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

    Cimmerians

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

    Scythians

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

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

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

    Comments

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

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

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

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

    A few interesting lessons to be learned:

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

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

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

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

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

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

    Related

    Mitogenomes show likely origin of elevated steppe ancestry in neighbouring Corded Ware groups

    west-yamna-corded-ware

    Open Access Mitochondrial genomes reveal an east to west cline of steppe ancestry in Corded Ware populations, by Juras et al., Scientific Reports (2018) 8:11603.

    Interesting excerpts (emphasis mine, references have been deleted for clarity):

    Ancient DNA was extracted from the Corded Ware culture individuals excavated in southeastern Poland (N = 12) and Moravia (N = 3). Late Eneolithic (N = 5) and Bronze Age human remains (N = 25) originated from western Ukraine and came from the Yampil barrow cemetery complex located in the north–western region of the Black Sea. Bronze Age individuals were associated with different archaeological cultures, including Yamnaya (N = 14), Catacomb (N = 2), Babyno (N = 4) and Noua (N = 5).

    The PCA results described 50.62% of the variability and were combined with the k-means clustering (with the k value of 5 as the best representation of the data, at the average silhouette of 0.2608). Based on these results individuals associated with the western and eastern Yamnaya horizon (YAE and YAW in Fig. 2) were grouped within a cluster consisting of populations from central Eurasia and Europe (blue cluster) including people associated with eastern Corded Ware culture (CWPlM) and Baltic Corded Ware culture (CWBal). This cluster did not contain any populations linked with early Neolithic farmers (red), or hunter-gatherers (green and yellow). On the other hand, k-means clustering linked the western Corded Ware culture-associated population (CWW) with Near East and Neolithic farmer ancestry groups from western and central Europe.

    pca-cwc-yamna
    Modified image, from the paper. PCA based on mitochondrial DNA haplogroup frequencies with k-means clustering. The two principal components explained 50.62% of the total variance. Loading vectors, representing mitochondrial haplogroup contributions, are highlighted as grey arrows. Populations are grouped into four clusters according to k-means. Population abbreviations are as follows: BABA – Bronze Age Balkans; CAT – Catacomb Culture; CWPlM – Corded Ware Culture from Poland and Moravia; CWBal – Baltic Corded Ware Culture; IAK – Iron Age Kazakchstan; IASI – Iron Age Syberia – Aldy Bel Culture; SCA – Scytho-Siberian Pazyryk (Altai); SCR – Rostov-Scythians, Samara; SCU – Scythians from Moldova and Ukraine; TAG – Tagar Culture; GAC – Globular Amphora Culture; YAW – western Yamnaya horizon population from Ukraine and Bulgaria; YAE – eastern Yamnaya horizon population; BAC – Baalberge Culture; BANE – Bronze Age Near East; BEC – Bernburg Culture; CHAHu – Chalcolithic Hungary; CWW – Corded Ware Culture west; CHABA – Chalcolitic Balkans; EBAG – Early Bronze Age Germany; FBC – Funnel Beaker Culture; IAG – Iron Age Germany; MNG – Middle Neolithic Germany; LBK – Linear Pottery Culture; LDN – Late Danubian Neolithic; MIC – Minoans; NEBA – Neolithic Balkans; PPNE – Pre-Pottery Near East; SCG – Schöningen group; SMC – Salzmünde Culture; AND – Andronovo Culture; BASI – Bronze Age Siberia; PWC – Pitted Ware Culture; HGE – eastern hunter-gatherers; NEUk- Neolithic Ukraine; HGS – southern hunter-gatherers; HGBal – Baltic hunter-gatheres; HGC – central huther-gatherers.

    Pairwise mtDNA-based FST values, visualized on MDS using the raw non-linearized FST (stress value = 0.099) (Fig. 4), also supported the PCA results and indicated that western and eastern Yamnaya horizon groups (YAW and YAE) were closer to people associated with the eastern Corded Ware culture (CWPlM) (FST = 0.00; FST = 0.01, respectively; both p > 0.05) and Baltic Corded Ware culture (CWBal) (FST = 0.00; FST = 0.00, respectively; both p > 0.05), than to populations associated with the western Corded Ware culture (CWW) (FST = 0.047 and FST = 0.059, respectively; both statistically significant p < 0.05). Western and eastern Yamnaya horizon groups also showed close genetic affinity to the Iron Age western Scythians (SCU) (FST = 0.0022 and FST = 0.006, respectively, both p > 0.05). The most distant populations to the Yamnaya horizon groups were western hunter-gatherers (HGW) (FST = 0.23 and FST = 0.15, p < 0.001).The FST-based MDS reflected the general European population history in the post-LGM period as the three highest FST scores were detected between western hunter-gatherers (HGW) and people associated with Linear Pottery culture (LBK) (FST = 0.33, p < 0.001), between eastern hunter-gatherers (HGE) and Baltic hunter-gatherers (HGBal) (FST = 0.35, p < 0.05), and between western (HGW) and eastern hunter-gatherers (HGE) (FST = 0.36, p < 0.05). The Yamnaya horizon groups (YAE and YAW) were placed centrally between northern hunter-gatherers (HGN) and Neolithic farmers (LDN), in direct proximity to the Bronze and Iron Age populations from Eastern Europe (SCU, BARu, SRU) and close to individuals associated with eastern and Baltic Corded Ware culture.

    yamna-corded-ware-pca
    Modified image, from the paper. In circles, relevant European groups for the question of ‘steppe ancestry’. MDS plot based on FST values calculated from mitochondrial genomes. Population abbreviations: BBC – Bell Beaker Culture; BAHu – Bronze Age Hungary; BARu – Bronze Age Russia; CWPlM – Corded Ware Culture from Poland and Moravia; CWW – western Corded Ware Culture; CWBal – Baltic Corded Ware Culture; EBAG – Early Bronze Age Germany; GAC – Globular Amphora Culture; HGE – eastern hunter-gatherers; HGN – northern hunter-gatherers; HGW – western hunter-gatherers; HGBal – Baltic hunter-gatherers; LBK – Linear Pottery Culture; LDN – Late Danubian Neolithic; MNE – Middle Neolithic; NENE – Near Eastern Neolithic; SCU – Scythians from Moldova and Ukraine; SRU – Rostov-Scythians, Samara.

    Among the analyzed samples, we identified two Catacomb culture-associated individuals (poz220 and poz221) belonging to hg X4. They are the first ancient individuals assigned to this particular lineage. Haplogroup X4 is rare among present day populations and has been found only in one individual each from Central Europe, Balkans, Anatolia and Armenia.

    Moreover, we have reported mtDNA haplotypes that might be associated with the migration from the steppe and point to genetic continuity in the north Pontic region from Bronze Age until the Iron Age. These haplotypes were assigned to hgs U5, U4, U2 and W3. MtDNA hgs U5a and U4, identified in this study among Yamnaya, Late Eneolithic and Corded Ware culture-associated individuals, have previously been found in high frequencies among northern and eastern hunter-gatherers. Moreover, they appeared in the north Pontic region in populations associated with Mesolithic (hg U5a), Eneolithic (Post-Stog) (hg U4), Yamnaya (hgs U5, U5a), Catacomb (hgs U5 and U5a) and Iron Age Scythians (hg U5a), suggesting genetic continuity of these particular mtDNA lineages in the Pontic region from, at least, the Bronze Age. Hgs U5a and U4-carrying populations were also present in the eastern steppe, along with individuals from the Yamnaya culture from Samara region, the Srubnaya and the Andronovo from Russia. Interestingly, hg U4c1 found in the Yamnaya individual (poz224) has so-far been found only in two Bell Beaker- associated individuals and one Late Bronze Age individual from Armenia, which might suggest a steppe origin for hg U4c1. A steppe origin can possibly also be assigned to hg U4a2f, found in one individual (poz282) but not reported in any other ancient populations to date, and to U5a1- the ancestral lineage of U5a1b, reported for individual poz232, which was identified not only in Corded Ware culture-associated population from central and eastern Europe, but also in representatives of Catacomb culture from the north Pontic region, Yamnaya from Bulgaria and Russia, Srubnaya and Andronovo-associated groups. Hg U2e, reported for Late Eneolithic individual (poz090), was also identified in western Corded Ware culture-associated individual and in succeeding Sintashta, Potapovka and Andronovo groups, suggesting possible genetic continuity of U2e1 in the western part of the north Pontic region.

    Hgs W3a1 and W3a1a, found in two Yamnaya individuals from this study (poz208 and poz222), were also identified in Yamnaya-associated individuals from the Russia Samara region and later in Únětice and Bell Beaker groups from Germany, supporting the idea of an eastern European steppe origin of these haplotypes and their contribution to the Yamnaya migration toward the central Europe. The W3a1 lineage was not identified in Neolithic times and, thus, we assume that it appeared in the steppe region for the first time during the Bronze Age. Notably, hgs W1 and W5, which predate the Bronze Age in Europe, were found only in individuals associated with the early Neolithic farmers from Starčevo in Hungary (hg W5), early Neolithic farmers from Anatolia (hg W1-T119C), and from the Schöningen group (hg W1c) and Globular Amphora culture from Poland (hg W5).

    west-yamna-west-corded-ware

    Some comments

    The most recent radiocarbon dates show that Early Yamna expanded to the west with Repin settlers of the Lower Don ca. 3350/3300 BC. At the end of the 4th millennium, then, these settlers dominated over groups whose population had in turn also elevated ‘steppe ancestry’ (at least from ca. 4000 BC, as shown by Ukraine Eneolithic samples from the forest-zone), and probably replaced the male population completely, as evidenced by other Yamna and Poltavka, and later Bell Beaker, Catacomb, and Sintashta samples.

    The ‘second wave’ of expansion of Yamna settlers to the west, into east-central European steppes, began probably ca. 3100/3000 BC, and – based on material culture – stemmed mainly from the North Pontic area. The Yampil Barrow Complex on the Dnieper (which I recently wrote about) seems to be part of one of the groups of western Yamna migrants: those who migrated westward from the left bank of the Dniester to the west into the Prut-Siret region, and north along the Prut.

    This region is the key for population movements that gave rise to the Corded Ware culture (see another recent post on Corded Ware origins). It is quite likely that we will see a dance of late Trypillia / Usatovo, GAC, (Proto-)Corded Ware, and Yamna samples in this area. Judging by the clear-cut Y-DNA bottlenecks we are seeing in Neolithic populations, especially among steppe pastoralists, the difference between groups in recovered ancient samples will not only be clear from their culture, but also from their male lineages.

    Based on the number of burials studied from the different settlement regions for West Yamna migrants, the Prut-Siret group was one of the smallest new Yamna ‘provinces’ in south-eastern Europe, and was probably overrun early, although – since kurgan findings continued into the Catacomb culture in the Yampil complex – the Dnieper region was well-enough connected to the core North Pontic area to be kept into its retreating territory by 2500 BC, as was the Danube delta, in contrast with other east-central European areas.

    steppe-chalcolithic-migrations
    Steppe-related migrations ca. 3100-2600 BC with tentative linguistic identification.

    Taking into account that the earliest Corded Ware burials are from ca. 2900 BC (in the Single Grave culture), and that the earliest A-horizon pottery expanded from Lesser Poland (a syncretic pottery based on the previous GAC-type) a century later, it is likely that what this paper shows for Corded Ware in eastern Europe and the Baltic is what I have suggested many times (see here, or here) as the most likely reason for elevated steppe ancestry (and close PCA cluster) of the Baltic LN ‘outliers’: the exogamy of Corded Ware groups with females from Yamna or a North Pontic steppe culture with similar ancestry.

    If Proto-Corded Ware populations of the North Pontic region did not have an identical “steppe ancestry” to these eastern CW groups already during the Eneolithic (which is the other possibility), I might be right in their more recent exogamy, and this could be seen in this study by the close cluster of east Corded Ware (especially Baltic) mtDNA to GAC and Yamna West groups, and distant from previous hunter-gatherer populations of the area, which suggests that expanding males from the Volhynia/Podolia region practiced exogamy mainly with southern groups.

    I think this is probably related to demographic pressure imposed on other populations by the explosive expansion of pastoralists with their new subsistence economy (part of the “Secondary Products Revolution”), which the hunter-gatherer and farmer population of Europe could not keep up with (as seen later in the admixture of expanding East Bell Beakers), although studies on European prehistoric demography are scarce and too general to tell us anything relevant for this precise period and region.

    Related

    The end of the Kura-Araxes settlements: large-scale phenomenon but with varied causes

    kura-araxes-indo-european-uralic-migrations

    Open access The End of the Kura-Araxes Culture as Seen from Nadir Tepesi in Iranian Azerbaijan, by Alizadeh, Maziar & Mohammadi, American Journal of Archaeology (2018) 122(3):463-477.

    Interesting excerpts (emphasis mine):

    The test trenches at Nadir Tepesi suggest that the Kura-Araxes occupation ended abruptly in the mid third millennium B.C.E. and that the site was then occupied or visited by a new group of people with new cultural traditions. Evidence for a significant destruction followed by the sharp discontinuity in the material culture could represent a violent termination of the Kura-Araxes occupation at Nadir Tepesi. This possibility provides one hypothesis for the end of the Kura-Araxes culture elsewhere as well in the Mughan Steppe.

    It appears that there is no subsequent substantial built settlement until possibly the Late Iron Age in the region. Our intensive and extensive surveys on the Mughan Steppe did not provide evidence for settlements until long after the Kura-Araxes time. For whatever reason, settlements on the Mughan Steppe seem to have reappeared only in the Iron Age and remained sparse until the Sassanian period in late antiquity.45 Although some ceramics with parallels in the Middle and Late Bronze Age and the Iron Age were found at a few sites, they do not seem to represent settlements.

    kura-araxes-sites-caucasus
    Major Kura-Araxes sites in the Caucasus region and location of Nadir Tepesi (modified from Bourrichon/Wikimedia Commons/CC BY-SA 3.0/GFDL).

    Indeed, except for the sites that may possibly contain burials, we do not know much about the Middle and Late Bronze Ages through the Iron Age in the Mughan Steppe. Similarly, archaeological investigations in the southern Caucasus do not provide information on settlements in the Middle Bronze Age.46 From a broad perspective, the abrupt and possibly violent end to the Kura-Araxes occupation at Nadir Tepesi, together with the sudden disappearance of the Kura-Araxes settlements and the scarcity of post–Kura-Araxes sites in the Mughan Steppe,47 may indicate that these changes were part of a larger phenomenon. This evidence could suggest a major sociocultural and demographic transformation at a regional level, at least in the western Caspian littoral plain, in the middle of the third millennium B.C.E. Other archaeological investigations in the southern Caucasus portray a similar picture, that of newcomers with a significantly different lifestyle and means of subsistence possibly associated with a mobile economy. Except in some elements of the ceramic traditions, evidence of continuity of Kura-Araxes traditions and their coexistence with newcomers is scarce and uncertain.48

    On one hand, Puturidze argues that there is no evidence supporting the notion of a migration of people into the southern Caucasus.50 Rather, she associates all the changes in the post–Kura-Araxes period with influences from Near Eastern societies as a result of developing interactions by the end of the third millennium B.C.E. On the other hand, Kohl hypothesizes the possibility of a “push-pull process”51 in which new groups of people with wheeled carts and oxen-pulled wagons gradually moved from the steppes of the north into the southern Caucasus, and the Kura-Araxes communities subsequently moved farther south.52.

    kura-araxes-late-iindo-european-uralic-migrations
    Early Chalcolithic migrations (3100-2600 BC)

    Kohl also reminds us of the evidence of increased militarism from the Early to the Late Bronze Age that is reflected in more fortified sites, new weaponry, and an iconography of war as seen on the Karashamb Cup.53 The appearance of defensive mechanisms such as fortification walls, which can be seen at Köhne Shahar, a Kura-Araxes settlement near Chaldran in Iranian Azerbaijan, further emphasizes the increase of intergroup conflicts and militarism during the Early Bronze Age, before the Kura-Araxes culture came to an end.54 Kohl argues that, while the number of Kura-Araxes settlements decreased in the southern Caucasus, archaeological research indicates that the Kura-Araxes culture spread to western Iran in the Zagros region and to the Levant.55 In Kohl’s view, as new groups of people moved in, the Kura-Araxes communities abandoned the southern Caucasus and moved farther south, where some of them already resided. Although some scholars suggest the possible movement of new groups of people from the northern steppes to the southern Caucasus,56 others associate the cultures of the post–Kura-Araxes period, especially the Trialeti.

    We believe that the evidence supports a less uniform scenario. The Kura-Araxes culture may have disappeared in various ways; the transition to the post–Kura-Araxes time may not be explained by a single model. Different Kura-Araxes settlements may have ended differently. The evidence from Nadir Tepesi could support a violent end at that site, and it is possible that similar evidence will be found at other sites in the Mughan Steppe. At some sites, such as Köhne Tepesi in the Khoda Afarin Plain,58 the Kura-Araxes occupation also ended abruptly but without any sign of destruction. In other regions, there may be evidence supporting the coexistence of newcomers with Kura-Araxes communities for some period.59 The results from Gegharot60 in Armenia and recent excavations by one of the authors of this report at Köhne Shahar, do not support any of these models. At Köhne Shahar, the Kura-Araxes culture ended around the middle of the third millennium B.C.E.61 In the last phase of Kura-Araxes occupation at the site, six storage jars in one of the workshop units stood intact, five of them still carefully covered by stone slabs. The evidence from Köhne Shahar may point to a nonviolent end or a planned abandonment of the site.62

    late-kura-araxes-indo-european-uralic-migrations
    Late Chalcolithic migrations (2600-2250 BC)

    The picture continues to be somehow blurred for what happened in the Caucasus and North Iran after the Late Indo-European expansions, due to contradictory information.

    With the analysis of the dataset from Narasimhan et al. (2018), it seemed that steppe peoples might have migrated into North Iran after the first Khvalynsk/Repin or Early Yamna expansions, because some samples from North Iran were reported to have steppe-related admixture.

    NOTE. As I already said, the Hajji Firuz sample of R1b-Z2103 subclade (of uncertain date) clusters closer to the Iron Age sample F38 from Iran (Broushaki et al. 2016), of the same subclade, which is quite likely related to Proto-Armenian speakers, so it is possible that both belong to the same, Late Bronze Age / Iron Age group of migrants.

    The other possibility, since it also clusters at a certain distance from the Hajji Firuz I4243 ‘outlier’, dated ca. 2326 BC (from the same archaeological site as other Chalcolithic samples, but being an intrusive Bronze Age burial), is that the Hajji Firuz sample is related to these hypothetical early migrations described here; or, that its date of I4243 is also not reliable…

    These initial reports, coupled with archaeological descriptions of potential migrants from the steppe ending the Kura-Araxes culture, may suggest that peoples of steppe origin (or peoples with steppe admixture from the Caucasus) occupied territories further to the south (see here for potential early migration waves).

    However, studies of samples from the Caucasus in Wang et al. (2018) have shown that no migrations related to EHG ancestry happened to the south, and that the minimal EHG/WHG contribution in Kura-Araxes individuals is probably part of the Anatolian farmer-related ancestry, and not from the steppe.

    In fact, further contribution from Iran Chalcolithic-related ancestry was found intruding to the north during the Early Bronze Age, into Kura-Araxes and Maykop-Novosvobodnaya samples. In the Middle Bronze Age, some peoples from the North Caucasus show steppe ancestry (further to the south than the first steppe ancestry incursions of the North Caucasus piedmont), but most late Caucasus groups studied retain the ‘southern’ Armenian/Iran Chalcolithic profile.

    trialeti-indo-european-uralic-migrations
    Early Bronze Age migrations (2600-2250 BC)

    All this casts doubts on the whole idea of intrusive steppe ancestry found in Iran Chalcolithic and Early Bronze Age (or, alternatively, on the proper dates of the Hajji Firuz ‘outliers’).

    Also, the archaeological discontinuity in the region until the Iron Age, and the close relationship of Armenian to Greek (relative to other Palaeo-Balkan languages, which seem to have expanded to the south-west with Yamna settlers), does not support these hypothetical early steppe migrants as the Proto-Armenian community; earlier migrations of LPIE speakers without known modern descendants are obviously possible, but no clear archaeological or linguistic link has been offered to date to support this.

    Until we have more samples with a clear archaeological and chronological context from Anatolia, Iran, and the Armenian Highlands during the Bronze and Iron Ages, and until they show clear steppe ancestry assessed in peer-reviewed papers (or at least thoroughly contrasted with other potential sources of such ancestry, and with solid statistical results), the question of intrusive steppe ancestry, and thus maybe LPIE-speakers (which may or may not be associated with Proto-Armenians) remains open.

    NOTE. The Armenian question remains open, not because genetics has precedence over linguistics, but because the linguistic classification and date of separation, in this case, is not clear, and may be quite old. The fact that Palaeo-Balkan and Pre-Indo-Iranian might have separated quite early within the Khvalynsk – Volga-Ural (Early Yamna) community adds to the difficulty in assessing migration routes, although I do believe that the close similarity of Armenian with Greek among Palaeo-Balkan languages do not warrant such an early separation, and the Middle to Late Bronze Age period in the Balkans and Anatolia offers a better route for this expansion.

    See also