The expansion of Indo-Europeans in Y-chromosome haplogroups

yamnaya-corded-ware-y-dna-haplogroups

I have been playing around a little more with GIS tools and haplogroups, and I managed to get some interesting outputs.

I made a video with a timeline of the evolution of Indo-European speakers, according to what is known today about reconstructed languages, prehistoric cultures and ancient DNA:

yamnaya-expansion

NOTE. The video is best viewed in HD 1080p (1920×1080) with a display that allows for this or greater video quality, and a screen big enough to see haplogroup symbols, i.e. tablet or greater. The YouTube link is here. The Facebook link is here.

Based on the results of the past 5 years or so, which have been confirming this combined picture every single time, I doubt there will be much need to change it in any radical way, as only minor details remain to be clarified.

Haplogroup maps

I wanted to publish a GIS tool of my own for everyone to have an updated reference of all data I use for my books.

The most complex GIS tools consume too many resources when used online in a client-server model, so I have to keep that to myself, but there are some ways to publish low quality outputs.

The files below include the possibility to zoom some levels to be able to see more samples, and also to check each one for more information on their ID, attributed culture and label, archaeological site, source paper, subclade (and people responsible for SNP inferences if any), etc.

Some usage notes:

  • Files are large (ca. 20 Mb), so they still take some time to load.
  • For the meaning of symbols and colors (for Y-DNA haplogroups), if there is any doubt, check the video above.
  • Pop-ups with sample information will work on desktop browsers by clicking on them, apparently not on smartphone and related tactile OS. I have changed the settings to show pop-ups on hover, so that it now works (to some extent) on tactile OS.
  • The search tool can look for specific samples according to their official ID, and works by highlighting the symbol of the selected individual (turning it into a bright blue dot), and leading the layer view to the location, but it seems to work best only with some browser and OS settings – in other browsers, you need to zoom out to see where the dot is located. The specific sample with its information could paradoxically disappear in search mode, so you might need to reload and look again for the same site that was highlighted.
  • Latitude and longitude values have been randomly modified to avoid samples overcrowding specific sites, so they are not the original ones.

Y-DNA

There are three versions:

  1. Labels with more specific subclades (including negative SNPs), using YTree for R1b samples (whenever it conflicts with YFull).
  2. Labels with YFull nomenclature.
  3. Simbols without labels (more symbols visible per layer).

y-dna-haplogroups

mtDNA

There are two versions:

  1. Symbols with labels.
  2. Symbols without labels.

NOTE. Because there are too many samples at the starting view, depending on the file you should zoom some levels to start seeing symbols.

mtdna-haplogroups

ADMIXTURE

I have tried running supervised ADMIXTURE models by selecting distant populations based on PCA and qpAdm results, but it seems to work fine only for a small K number, being easily improved when running it unsupervised.

Adding distant populations seems to improve or mess up with the results in unpredictable ways, too, so at this point I doubt ADMIXTURE (or anything other than qpAdm) is actually useful to obtain anything precise in terms of ancestry evolution, although it can give a good overall idea of rough ancestry changes, if K is kept small enough.

Anyway, I will keep trying to find a simple way to show the actual evolution and expansion of “Steppe ancestry”. Since every single run for thousands of samples takes days, I don’t really know if and when I will find something interesting to show…

See also

R1b-L23-rich Bell Beaker-derived Italic peoples from the West vs. Etruscans from the East

final-bronze-age-italy

New paper (behind paywall) Ancient Rome: A genetic crossroads of Europe and the Mediterranean, by Antonio et al. Science (2019).

The paper offers a lot of interesting data concerning the Roman Empire and more recent periods, but I will focus on Italic and Etruscan origins.

NOTE. I have updated prehistoric maps with Y-DNA and mtDNA data, and also the PCA of ancient Eurasian samples by period including the recently published samples, now with added sample names to find them easily by searching the PDFs.

Apennine homeland problem

The traditional question of Italic vs. Etruscan origins from a cultural-historical view* lies in the opposition of the traditional way of life during the Bronze Age as opposed to increasingly foreign influences in the Final Bronze Age, which eventually brought about a proto-urban period in the Apennine Peninsula.

* From a modern archaeological perspective, as well as from the (unrelated) nativist view, “continuity” of ancient cultures, languages, and peoples is generally assumed, so this question is a no-brainer. Seeing how population genomics has essentially supported the cultural-historical view, dismissing the concepts of unscathed genomic or linguistic continuity, we have to assume that different cultures potentially represent different languages, and that genetic shift coupled with radical cultural changes show a strong support for linguistic change, although the later Imperial Roman period is an example of how this is not necessarily the case.

bronze-age-polada-proto-apennine
Early Bronze Age cultures ca. 2200 – 1750 BC. See full maps.

A little background to the Italic vs. Etruscan homeland problem, from Forsythe (2006) (emphasis mine):

While the material culture of the Po Valley developed in response to influences from central Europe and the Aegean, peninsular Italy during the late Bronze Age lagged somewhat behind for the most part. Inhumation continued to be the funerary practice of this region. Although agriculture doubtless remained the mainstay of human subsistence, other evidence (the occupation of mountainous sites not conducive to farming, the remains of cattle, sheep, pigs, and goats, and ceramic vessels used for boiling milk and making cheese) indicates that pastoralism was also very widespread. This suggests that transhumance was already a well-established pattern of human existence. In fact, since the material culture of central and southern Italy was relatively uniform at this time, it has been conjectured that this so-called Apennine Culture of c. 1600–1100 B.C. owed its uniformity in part to the migratory pattern characteristic of ancient Italian stockbreeding.

During the first quarter of the twelfth century B.C. the Bronze-Age civilizations of the eastern Mediterranean came to an abrupt end. The royal palaces of Pylos, Tiryns, and Mycenae in mainland Greece were destroyed by violence, and the Hittite kingdom that had ruled over Asia Minor was likewise swept away. The causes and reasons for this major catastrophe have long been debated without much scholarly consensus (see Drews 1993, 33–96). Apart from the archaeological evidence indicating the violent destruction of many sites, the only ancient accounts relating to this phenomenon come from Egypt. The most important one is a text inscribed on the temple of Medinet Habu at Thebes, which accompanies carved scenes portraying the pharaoh’s military victory over a coalition of peoples who had attempted to enter the Nile Delta by land and sea.

sea-peoples-egypt-rameses-iii

Iron metallurgy did not reach Italy until the ninth century B.C., and even then it was two or more centuries before iron displaced bronze as the most commonly used metal. Thus, archaeologists date the beginning of the Iron Age in Italy to c. 900 B.C.; and although the Italian Bronze Age is generally assigned to the period c. 1800–1100 B.C. and is subdivided into early, middle, and late phases, the 200-year interval between the late Bronze Age and early Iron Age has been labeled the Final Bronze Age.

During this period the practice of cremation spread south of the Po Valley and is attested at numerous sites throughout the peninsula. Since this cultural tradition developed into the Villanovan Culture which prevailed in Etruria and much of the Po Valley c. 900–700 B.C., modern archaeologists have devised the term “Proto-Villanovan” to describe the cremating cultures of the Italian Final Bronze Age.

The fact that some of the earliest urnfield sites of peninsular Italy are located on the coast (e.g. Pianello in Romagna and Timmari in Apulia) is interpreted by some archaeologists as an indication that cremating people had come into Italy by sea, and that their migration was part of the larger upheaval which affected the eastern Mediterranean at the end of the Bronze Age (so Hencken 1968, 78–90). On the other hand, the same data can be explained in terms of indigenous coastal settlements adopting new cultural traits as the result of commercial interaction with foreigners. In any case, by the end of the Final Bronze Age inhumation had reemerged as the dominant funerary custom of southern Italy, but cremation continued to be an integral aspect of the Villanovan Culture of northern and much of central Italy.

etruscan-world
Diffusion of the Villanovan culture (after M. Torelli, ed., Gli Etruschi, Milan, 2000, p. 45). Modified from The Etruscan World (2013), by Turfa.

There is a myriad of linguistic reasons why eastern foreign influences can be attributed to Indo-European (mainly Anatolian, including a hypothetic influence on Latino-Faliscan) or Tyrsenian – as well as many other less credible models – and there is ground in archaeology to support any of the linguistic models proposed, given the long-lasting complex interactions of Italy with other Mediterranean cultures.

NOTE. The lack of theoretical schemes including integral archaeological-linguistic cultural-historical models due to the radical reaction against the excesses of the early 20th century have paradoxically allowed anyone (from archaeologists or linguists to laymen) to posit infinite population movements often based on the simplest similarities in vase decoration, burial practices, or shared vocabulary.

However, recent studies in population genomics have simplified the picture of Bronze Age population movements, identifying radical changes related to population replacements as opposed to more subtle admixture events. As of today, (France Bell Beaker-like) Urnfield stands as the most likely vector of Celtic languages; NW Iberian Bell Beakers as the vector of Galaico-Lusitanian; NW Mediterranean Beakers as the most likely ancestors of Elymian; the Danish Late Neolithic as representative of expanding Proto-Germanic; or Central-East Bell Beakers of Proto-Balto-Slavic.

With this in mind, the most logical conclusion is to assume that Alpine Bell Beakers (close to the sampled Italian Beakers from Parma or from southern Germany) spread Italo-Venetic languages, which is deemed to have split in the early to mid-2nd millennium BC, with dialects found widespread from the Alps to Sicily by the early 1st millennium BC.

Therefore, the two main remaining models of Italian linguistic prehistory – with the information that we already had – were as follows, concerning Tyrsenian (the ancestor of Etruscan and Rhaetian):

  1. It is a remnant language of the Italian (or surrounding) Chalcolithic, which survived in some pockets isolated from the Bell Beaker influence;
  2. It was a foreign language that arrived and expanded at the same time as the turmoil that saw the emergence of the Sea Peoples.

NOTE. Read more on Italo-Venetic evolution and on the likely distribution of Old European and Tyrsenian in the Bronze Age.

Italic-venetic-etruscan-languages-map
Languages of pre-Roman Italy and nearby islands. Italo-Venetic languages surrounded with shadowed red border. I1, South Picene; I2, Umbrian; I3, Sabine; I4, Faliscan; I5, Latin; I6, Volscian and Hernican; I7, Central Italic (Marsian, Aequian, Paeligni, Marrucinian, Vestinian); I8, Oscan, Sidicini, Pre-Samnite; I9, Sicel; IE1, Venetic; IE2, North Picene; IE3, Ligurian; IE4, Elymian; IE5, Messapian; C1, Lepontic; C2, Gaulish; G1-G2-G3, Greek dialects (G1: Ionic, G2: Aeolic, G3: Doric); P1, Punic; N1, Rhaetian; N2, Etruscan; N3, Nuragic. Image modified from Davius Sanctex.

Proto-Villanovan

A Proto-Villanovan female from Martinsicuro in the Abruzzo coast (ca. 890 BC), of mtDNA hg. U5a2b, is the earliest mainland sample available showing foreign (i.e. not exclusively Anatolia_N ± WHG) ancestry:

Martinsicuro is a coastal site located on the border of Le Marche and Abruzzo on central Italy’s Adriatic coast. It is a proto-Villanovan village, situated on a hill above the Tronto river, dating to the late Bronze Age and Early Iron Age (…) finds from the site indicate an affinity with contemporaries in the Balkans, suggesting direct trade contacts and interaction across the Adriatic. In particular, the practice of decorating ceramics with bronze elements was shared between the Nin region in Croatia and Picene region of Italy, including Martinsicuro.

NOTE. These are just some of the models I have tried, most of them unsuccessfully. The standard errors that I get are too high, but I am not much interested in this sample that seems (based on its position in the PCA and the available qpAdm results) mostly unrelated to Italic and Etruscan ethnogenesis.

The sample clusters close to the Early Iron Age sample from Jazinka (ca. 780 BC), from the central Dalmatian onomastic region, on the east Adriatic coast opposite to Abruzzo, possibly related to the south-east Dalmatian (or Illyrian proper) onomastic region to the south. However, there is no clear boundary between hydrotoponymic regions for the Bronze Age, and it is quite close to the (possibly Venetic-related) Liburnian onomastic region to the north, so the accounts of Martinsicuro belonging to the Liburni in proto-historical times can probably be extrapolated to the Final Bronze Age.

NOTE. Based on feminine endings in -ona in the few available anthroponyms, Liburnian may have shared similarities with personal names of the Noricum province, which doesn’t seem to be related to the more recent (Celtic- or Germanic-related?) Noric language. On the other hand, anthroponyms are known to show the most recent hydrotoponymic layer of a region, so these personal names might be unrelated to the ancestral language behind place and river names.

dalmatian-toponymic-liburnian
Toponyms ending in -ona (after S. Čače 2007).

Villanovan

A Villanovan sample from the powerful Etruscan city-state of Veio in the Tyrrhenian coast (ca. 850 BC), to the north of Rome, shows a cluster similar to later Etruscans and some Latins. Veio features prominently in the emergence of the Etruscan society. From The Etruscan World (2013) by Turfa:

In the final phase of the Bronze Age (mid-twelfth to tenth century bc) the disposition of settlements appears to be better distributed, although they are no longer connected to the paths of the tratturi (drove roads for transhumance of flocks and herds) as they had been during the Middle Bronze Age. As evidence of the intensive exploitation of land and continuous population growth there are now known in Etruria at least 70 confirmed settlements, and several more sites with indications of at least temporary occupation. The typical town of this chronological phase generally occupies high ground or a tufa plateau of more than five hectares, isolated at the confluence of two watercourses. These small plateaus, naturally or artificially protected, are not completely built up: non-residential areas within the defenses were probably intended as collecting points for livestock or zones reserved for cultivation, land used only by certain groups, or areas designated for shelter in case of enemy attack.

Taken together, the data seem to indicate the presence of individuals or families at the head of different groups. And in the final phase of the Bronze Age, there must have begun the process that generated (at least two centuries later) a tribal society based on families and the increasingly widespread ownership of land.

In the ninth century bc the territory is divided instead into rather large districts, each belonging to a large village, divided internally into widely spaced groups of huts, and into a small number of isolated villages located in strategic positions, for which we can assume some form of dependence upon the larger settlements.

etruscan-proto-urban
Schematic reconstruction of the birth of a proto-urban center (after P. Tamburini, II Museo
territoriale del Lago di Bolsena. Vol 1. Dalle origini alperiodo etrusco, Bolsena 2007). Modified from The Etruscan World (2013), by Turfa.

Compared to the preceding period, this type of aggregation is characterized by a higher concentration of the population. To the number of villages located mostly on inaccessible plateaus, with defensive priority assigned to the needs of agriculture, are added settlements over wide plains where the population was grouped into a single hilltop location. It is a sort of synoikistic process, so, for example, at Vulci people were gathered from the district of the Fiora and Albegna Rivers, while to Veii came the communities that inhabited the region from the Tiber River to Lake Bracciano, including the Faliscan and Capenate territories. The reference to Halesos, son of Saturn, the mythical founder of Falerii in the genealogy of Morrius the king of Veii (Servius, Commentary on Aeneid 8.285) may conceal this close relationship between Veii and the Ager Faliscus (the territory of the historical Faliscans).

The great movement of population that characterizes this period is unthinkable without political organizations that were able to impose their decisions on the individual village communities: the different groups, undoubtedly each consisting of nuclei linked by bonds of kinship, located within or outside the tufa plateaus that would be the future seats of the Etruscan city-states, have cultural links between them, also attested to by the analysis of craft production, such as to imply affiliation to the same political unit and enabling us to speak of such human concentrations as “proto-urban”.

etruscan-expansion-padania
Map of Etruria Padana. Left: From 9th to 8th century BC. Right: From 6th to 4th century BC. Dipartimento di Archeologia di Bologna. Modified from The Etruscan World (2013), by Turfa.

Italic vs. Etruscan origins

Four out of five sampled Latins show Yamnaya-derived R1b-L23 lineages, including three R1b-U152 subclades, and one hg. R1b-Z2103 (in line with the variability found among East Bell Beakers), while one from Ardea shows hg. T1a-L208. A likely Volscian (i.e. Osco-Umbrian-speaking) sample from Boville Ernica also shows hg. R1b-Z2118*, an ‘archaic’ subclade within the P312 tree. These R1b-L23 subclades are also found later during the Imperial period, although in lesser proportion compared to East Mediterranean ones.

Among Etruscans, the only male sampled shows hg. J2b-CTS6190* (formed ca. 1800 BC, TMRCA ca. 1100 BC), sharing parent haplogroup J2b-Y15058 (formed ca. 2400 BC, TMRCA ca. 1900 BC) with a Croatian MBA sample from Veliki Vanik (ca. 1580 calBCE), who also clusters close to the IA sample from Jazinka.

Given the position of Latins and Etruscans in the PCA and the likely similar admixture, it is not striking that differences are subtle. From Antonio et al. (2019):

Interestingly, although Iron Age individuals were sampled from both Etruscan (n=3) and Latin (n=6) contexts, we did not detect any significant differences between the two groups with f4 statistics in the form of f4(RMPR_Etruscan, RMPR_Latin; test population, Onge), suggesting shared origins or extensive genetic exchange between them.

On the other hand, there are 3 clear outliers among 11 Iron Age individuals, and all Iron Age samples taken together form a wide Etrurian cluster, so it seems natural to test them in groups divided geographically:

Results seem inconsistent, especially for Italic peoples, due to their wide cluster. It could be argued that the samples with ‘northern’ admixture – a Latin from Palestrina Colombella (of hg. R1b-Z56) and the Volscian sample – might represent better the Italic-speaking population before the proto-urban development of Latium, especially given the reported strong Etruscan influences among the Rutuli in Ardea, which might explain the common cluster with Etruscans and the outlier with reported ‘eastern’ admixture.

etruscan-latino-faliscan-osco-umbrian-italic-languages
Languages of Central Italy at the beginning of Roman expansion. Image modified from original by Susana Freixeiro at Wikipedia.

It makes sense then to test for a group of Etruscans (adding the Villanovan sample) and another of Italic peoples, to distinguish between a hypothetic ancestral Italic ancestry from a Tyrrhenian one:

NOTE. Fine-tuning groups based on the position of samples in the PCA or the amount of this or that component, or – even worse – based on the good or bad fits relative to the tested populations risks breaking the rules of subgroup analysis, eventually obtaining completely useless results, so interpretations for the Italic cluster need to be taken with a pinch of salt (until more similar Italic samples are published). The lack of proper rules regarding what can and cannot be done with this combined archaeological – genomic research is already visible to some extent in genetic papers which use brute force qpAdm tests for all available sampled populations, instead of selecting those potentially ancestral to the studied groups.

Tabs are organized from ‘better’ to ‘worse’ fits. In this case, as a general guide to the spreadsheets, the first tabs (to the left) show better fits for Italic peoples, and as tabs progress to the right they show ‘better’ fits for Etruscans, until it reaches the ‘infeasible’ or otherwise bad models.

This is what can be inferred from the models:

1) Steppe ancestry: Italic peoples seem to show better fits for north-western Alpine sources, closest to Bell Beakers from France or South Germany; whereas Etruscans show a likely Transdanubian source, closest to late Bell Beakers from Hungary (excluding Steppe- and WHG-related outliers).

To see if Bell Beakers from the south-west could be related, I tried the same model as in Fernandes et al. (2019), selecting Iberian BBC samples with more Steppe ancestry – to simplify my task, I selected them according to their PCA position. In a second attempt, I tried adding those intermediate with Iberia_CA, and it shows decreasing p-values, suggesting that the most likely source is close to high Steppe-related Bell Beaker populations. In both cases, models seem worse than France or Germany Bell Beakers.

Since Celtic spread with France BBC-like Urnfield peoples, and Italic peoples appear to be also ancestrally connected to this ancestry, the most plausible explanation is that they share an origin close to the Danubian EBA culture, which would probably be easily detectable by selecting precise Bell Beaker groups from South Germany.

expansion-celtic-peoples
Hypothetic expansion of Celtic-speaking peoples during the La Tène period (source). Image used in Udolph (2009) because it reflects a homeland roughly coincident with the oldest Celtic hydrotoponymy.

2) Anatolia_Neolithic ancestry: different tests seem to show that fits for EEF-related ancestry get warmer the closer the source population selected is to North-West Anatolian farmers, in line with the apparent shift from the East Bell Beaker cluster toward the Anatolia Neolithic cluster in the PCA:

These analyses suggest that there was a renewed Anatolia_N-like contribution during the Bronze Age, older than these Iron Age populations, but later than the rebound of WHG ancestry found among Late Neolithic and Chalcolithic samples from Italy, Sicily, or Sardinia, reflected in their shift in the PCA towards the WHG cluster.

From a range of chronologically closer groups clustering near Anatolia_N, the source seems to be closest to Neolithic samples from the Peloponnese. The direct comparison of Greece_Peloponnese_N against Italy_CA in the analyses labelled “Strict” shows that the sampled Greece Late Neolithic individuals are closer to the source of Neolithic ancestry of Iron Age Etrurians than the Chalcolithic samples from Remedello, Etruria, or Sardinia.

NOTE. Most qpAdm analyses are done with a model similar to Ning et al. (2019), using Corded_Ware_Germany.SG as an outgroup instead of Italy_Villabruna, because I expected to test all models against Yamnaya, too, but in the end – due to the many potential models and my limited time – I only tested those with ‘better’ fits:

Using Yamnaya_Kalmykia as outgroup gives invariably ‘worse’ results, as expected from Bell Beaker-derived populations who are directly derived from Yamnaya, despite their potential admixture with local Corded Ware peoples through exogamy during their expansion in Central Europe. The differences between Italic and Etruscan peoples have to be looked for mainly in EEF-related contributions, not in Steppe-related populations.

pca-italic-etruscan-latins-villanovan
Detail of the PCA of Eurasian samples, including Italian samples from Antonio et al. (2019) with the selected clusters of Italic vs. Etruscans, as well as Bell Beaker and Balkan BA and related clusters and outliers. Also marked are Peloponnese Late Neolithic (Greece_N), Minoans, Mycenaeans and Armenian BA samples. See image with better resolution.

Etruscans and Sea Peoples

The sister clade of the Etruscan branch, J2b-PH1602 (TMRCA ca. 1100 BC), seems to have spread in different directions based on its modern distribution, and their global parent clade J2b-Y15058 (TMRCA ca. 1900 BC) was previously found in Veliki Vanik. J2b-L283 appears related to Neolithic expansions through the Mediterranean, based on its higher diversity in Sardinia, although its precise origin is unclear.

Based on the modern haplogroup distribution and on the TMRCA, it can be assumed that a community spread with hg. J2b-Z38240 from somewhere close to the Balkans coinciding with the population movements of the Final Bronze Age. Whether this haplogroup’s Middle Bronze Age area, probably close to the Adriatic, was initially Indo-European-speaking or was related to a regional survival of Etruscan-speaking communities remains unclear.

Greece Late Neolithic is probably the closest available population (from those sampled to date) geographically and chronologically to the Bronze Age North-Western Anatolian region, where the Tyrsenian language family is hypothesized to have expanded from.

We only have a few Iron Age samples from Etruria, dating from a period of complex interaction in the Mediterranean – evidenced by the relatively high proportion of outliers – so it is impossible to discard the existence of some remnant Bronze Age population closer to the Adriatic – from either the Italian (Apulia?) or the Balkan coasts – expanding with the Proto-Villanovan culture and responsible for the Greece_LN-like ancestry seen among the sampled Final Bronze / Iron Age populations from central Italy.

On the other hand, taking into account the ancestry of available Italian, Sardinian and Sicilian Neolithic, Chalcolithic and Bronze Age samples, the current genetic picture suggests an expansion of a different North-West Anatolia Neolithic-related population after the arrival of Bell Beakers from the north, hence probably through the Adriatic rather than through the Tyrrhenian coast, whether the common language group formed with Lemnian had a more distant origin in Bronze Age North-West Anatolian groups or in some isolated coastal community of the Adriatic.

NOTE. Admittedly, the ancestry of the Proto-Villanovan sample seems different from that of Etruscans, although a contribution of the most likely sources for Etruscans cannot be rejected for the Proto-Villanovan individual (see ‘reciprocal’ models of admixture here). In any case, I doubt that the main ancestry of the Proto-Villanovan from Abruzzo is directly related to the population that gave rise to Etruscans, and is more likely related to recent, intense bilateral exchanges in the Adriatic between (most likely) Indo-European-speaking populations.

violin-bow-fibula-italy-illyria-aegean-crete
The distribution of violin bow fibula from thirteenth century onward showing the movement of people between northern Italy, Illyria and the Aegean, Crete, and the parallel distribution of “foreign” darksurfaced handmade pottery (based on Kasuba 2008 : abb. 15; Lis 2009 ). Modified from Kristiansen (2018).

Northern Adriatic

This Adriatic connection could in turn be linked to wider population movements of the Final Bronze Age. Proto-Villanova represents the introduction of oriental influences coinciding with the demise of the local Terramare culture (see e.g. Cremaschi et al. 2016), whereas the Villanovan culture shows partial continuity with many Proto-Villanovan settlements where Etruscan-speaking communities later emerge. From Nicolis (2013):

Founded in the LBA, the village of Frattesina extended over around 20 hectares along the ‘Po di Adria’, a palaeochannel of the Po. It experienced its greatest development between the twelfth and eleventh centuries BC, when it had a dominant economic role thanks to an extraordinary range of artisan production (metalworking, working of bone and deer horn, glass) and major commercial influence due to trading with the Italian Peninsula and the eastern Mediterranean.

This is demonstrated by the presence of exotic objects and raw materials, such as Mycenaean pottery, amber, ivory, ostrich eggs, and glass paste. For the Mycenaean sherds found in settlements in the Verona valleys and the Po delta, analysis of pottery fabrics has shown that some of them very probably come from centres in Apulia where there were Aegean craftsmen and workers, whereas others would seem to have originated on the Greek mainland (Vagnetti 1996; Vagnetti 1998; Jones et al. 2002).

acqua-fredda-passo-del-redebus
Reconstruction of Acqua Fredda archaeological site, Passo del Redebus, where a group of 9 smelting furnaces has been discovered dating back to the Late Bronze Age (8-9th century BC). Image modified from Trentino Cultura.

In this context a particular system of relations seems to link one specific Alpine region with the social and economic structure of the groups settling between the Adige and the Po and the eastern Mediterranean trading system. In eastern Trentino, at Acquafredda, metallurgical production on a proto-industrial scale has been demonstrated between the end of the LBA and the FBA (twelfth–eleventh centuries BC) (Cierny 2008) (Fig. 38.3). These products must have supplied markets stretching beyond the local area, linked to the Luco/Laugen culture typical of the central Alpine environment. According to Pearce and De Guio (1999), such extensive production must have been destined for the supply of metal to other markets, first of all to other centres on the Po plain, where transactions for materials of Mediterranean origin also took place.

The picture of the Final Bronze Age of these regions, which seems to be coherent with the development of the cultural setting of the Early Iron Age, shows that the birth of the proto-urban Villanovan centres of Bologna in Emilia and Verucchio in Romagna, at the beginning of the Iron Age, seems to follow a line of continuity starting with the role played by Frattesina in the Final Bronze Age (Bietti Sestieri 2008).

naue-swords-final-bronze-age
Reconstruction of pan-European communication network represented by the geographical spread of archaeological objects. The network nodes represent sites that have yielded an above-average number of relevant finds. The links are direct connections between neighbouring nodes. Modified from Suchowska-Ducke (2015).

Tyrsenian

The close similarities shared by Rhaetian with the oldest Etruscan inscriptions – but not with the language of later periods, when Etruscan expanded further north – together with increased ‘foreign’ contacts in the Final Bronze Age and the ‘foreign’ ancestry of Etruscans (relative to Italian Chalcolithic and to near-by Bell Beakers) support a language split close to the Adriatic, and not long before they started using the Euboean-related Old Italic alphabet. All this is compatible with an expansion associated with the Proto-Villanovan period, possibly starting along the Po and the Adige.

From Nicolis (2013):

In this geographical context the most important morphological features are the Alps and the alluvial plain of the River Po. Since Roman times the former have always been considered a geographical limit and thus a cultural barrier. In actual fact the Alps have never really represented a barrier, but instead have played an active role in mediating between the central European and Mediterranean cultures. Some of the valleys have been used since the Mesolithic as communication routes, to establish contacts and for the exchange of materials and people over considerable distances. The discovery of Ötzi the Iceman high in the Alps in 1991 demonstrated incontrovertibly that this environment was accessible to individuals and groups from the end of the fourth millennium BC.

From the Early Neolithic period the plain of the Po Valley provided favourable conditions for the population of the area by human groups from central and eastern Europe, who found the wide flat spaces and fertile soils an ideal environment for developing agricultural techniques and animal husbandry. Lake Garda represents a very important morphological feature, benefiting among other things from a Mediterranean-type microclimate, the influence of which can already be seen in the Middle Neolithic. Situated between the plain and the mountains, the hills have always offered an alternative terrain for demographic development, equally important for the exploitation of economic and environmental resources.

As documented for previous periods, in the late and final phases of the Bronze Age the northern Adriatic coast would also seem to represent an important geographical feature, above all in terms of possible long-distance trading contacts with the Aegean and eastern Mediterranean coasts. However, the geographical and morphological characteristics and the river network in this area were very different to the way they are today, and the preferred communications routes must always have been the rivers, particularly the Po and the Adige.

etruscan-rhaetian-inscriptions
Map of inscriptions of Northern Italy. In green, Rhaetian inscriptions; in Pink, Etruscan inscriptions. Arrows show potential language movements through the Po and the Adige based on the relationship between both language. Image modified from Raetica.

Conclusion

Although it seems superfluous at this point, finding mostly Yamnaya-derived R1b-L23 lineages among speakers of another early North-West Indo-European dialect – and also the earliest to have split into its attested dialects – gives still more support to Yamnaya steppe herders as the vector of expansion of Late PIE, and their continuity up to the Iron Age also supports the strong patrilineal ties of Indo-Europeans.

This, in turn, further supports the nature of Afanasievo as the earliest separated branch from a Late Proto-Indo-European trunk, and of Khvalynsk as the Indo-Anatolian community, while a confirmation of R1b-L23 among early Greeks (speaking the earliest attested Graeco-Aryan dialect) will indirectly confirm East Yamnaya/Poltavka as the early Proto-Indo-Iranian community.

As it often happens with genetic sampling, due to many uncontrollable factors, there is a conspicuous lack of a proper regional and chronological transect of Bell Beaker and Bronze Age samples from Italy, which makes it impossible to determine the origin of each group’s ancestral components. Even though the sampled Italian Beakers don’t seem to be the best fit for Iron Age Italic-speaking peoples from Etruria, they still might have formed part of the migration waves that eventually developed the Apennine culture together with those of prevalent West-Central European Bell Beaker ancestry.

Similarly, the visible radical change from the increasingly WHG-shifted Italian farmers up to the sampled Chalcolithic individuals, including Parma Bell Beakers, to the Anatolia_N-shifted ancestry found in Iron Age Etruscans and Latins might be related to earlier population movements associated with Middle or Late Bronze Age contacts, and not necessarily to the radical social changes seen in the Final Bronze Age. The Etruscan subclade with a likely origin in the Balkans, on the other hand, suggests recent migrations from the Adriatic into Etruria.

middle-bronze-age-italy
Middle Bronze Age cultures of Italy and its surroundings ca. 1750-1250 BC. Potential source of the Greece_N-like admixture found widespread during the Iron Age. See full maps.

Until there is more data about these ancestry changes in Italy, the Balkans, and North-West Anatolia, I prefer to leave the Tyrsenian origins up in the air, so I deleted the Lemnian -> Etruscan arrow of the map of Late Bronze Age migrations, if only because an arrival through the Tyrrhenian Sea has become much less likely. An East -> West movement is still the most likely explanation for the common Tyrsenian language, culture, and ancestry, but the only Y-DNA haplogroup available seems to have an origin closer to the Adriatic.

The recent study of Sea Peoples showed – based on the previous hypothesis of the language and culture of the Philistines – that a minority of incoming elites must have imposed the language as their genetic ancestry (including haplogroups) became diluted among a majority of local peoples. Similarly, the original genetic pool of Tyrsenian speakers might have become diluted among different groups due to their more complex social organization, similar to what happened to Italic peoples during the Imperial period.

One of the most interesting aspects proven in the paper – and strongly suspected before it – is the reflection in population genomics of the change in the social system of the Italian Peninsula during the Roman expansion, and even before it during the Etruscan polity. In fact, it was not only Romans who spread and genetically influenced other European regions, but other regions – especially the more numerous Eastern Mediterranean populations – who became incorporated into a growing Etrurian community which nevertheless managed to spread its language.

In other words, Tyrsenian spread through central and northern Italy, and Latin throughout the whole Mediterranean area and mainland Europe, not (only) through population movements, but through acculturation, in a growing international system of more complex political organizations that can be inferred for most population and language expansions since the Early Iron Age. East Mediterranean populations, Scythians and other steppe peoples, East Germanic peoples, Vikings, or North-Eastern Europeans are other clear examples known to date.

Related

“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.

#EDIT (22 NOV 2019): New preprint Gene-flow from steppe individuals into Cucuteni-Trypillia associated populations indicates long-standing contacts and gradual admixture, by Immel et al. bioRxiv (2019), on Gordinești samples from Moldova ca. 3500-3100 BC. Relevant excerpts (emphasis mine):

A principal component analysis of the four Moldova females together with previously published data sets of ancient Eurasians showed that Gordinești, Pocrovca 1 and Pocrovca 3 grouped with later dating Bell Beakers from Germany and Hungary close to the four CTC males from Verteba, while Pocrovca 2 fell into the LBK cluster next to Neolithic farmers from Anatolia and Starčevo individual.

When looking at various proxies for steppe-related ancestry (Yamnaya Samara, Ukraine Mesolithic, Caucasian hunter-gatherer (CHG), Eastern hunter gatherer (EHG)), we did not observe any significant difference in genetic influx from either Yamnaya Samara, EHG or Ukraine Mesolithic. However, relative to CHG, we detected a substantial shift towards Yamnaya Samara steppe-related ancestry. Consequently, Yamnaya Samara, Ukraine Mesolithic and EHG appear to be equally suitable proxies for steppe-related ancestry in the Moldovan CTC individuals.

We did not obtain feasible models when running qpAdm on the X-chromosome in order to test for male-biased admixture from hunter-gatherers or individuals with steppe-related ancestry.

It is not surprising that Gordinești, Pocrovca 1 and Pocrovca 3 showed genetic affinities with later dating Bronze Age or Bell Beaker individuals. The common link among them is the considerable steppe-related ancestry, which each group likely received independently from different parental populations.

pca-trypillia-verteba-pocrovka-gordinesti
Principal component analysis of the CTC individuals from Moldova (Gordinești, Pocrovca 1, Pocrovca 2, Pocrovca 3) in red and the CTC individuals from Verteba Cave (I1926, I2110, I2111, I3151) in blue together with 23 selected ancient populations/individuals projected onto a basemap of 58 modern-day West Eurasian populations (not shown). HG=hunter-gatherer, LBK=Linearbandkeramik, PU=Proto-Unetice, TRB=Trichterbecher (Funnel Beaker Culture, FBC). PC1 is shown on the x-axis and PC2 on the y-axis.

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

Corded Ware and Bell Beaker related groups defined by patrilocality and female exogamy

tumulus-culture-eba-danube

Two new interesting papers concerning Corded Ware and Bell Beaker peoples appeared last week, supporting yet again what is already well-known since 2015 about West Uralic and North-West Indo-European speakers and their expansion.

Below are relevant excerpts (emphasis mine) and comments.

#UPDATE (27 OCT 2019): I have updated Y-DNA and mtDNA maps of Corded Ware, Bell Beaker, EBA, MBA, and LBA migrations. I have also updated PCA plots, which now include the newly reported samples and those from the Tollense valley, and I have tried some qpAdm models (see below).

I. Corded Ware and Battle Axe cultures

Open access The genomic ancestry of the Scandinavian Battle Axe Culture people and their relation to the broader Corded Ware horizon, by Malmström, Günther, et al. Philos. Trans. R. Soc. (2019).

I.1. Origins of Corded Ware peoples

The discovery of the Alexandria outlier represented a clear support for a long-lasting genomic difference between the two distinct cultural groups, Yamnaya and Corded Ware, already visible in an opposition Khvalynsk vs. late Sredni Stog ca. 4000 BC, i.e. well before the formation of both Late Eneolithic/Early Bronze Age groups.

However, the realization that it may not have been an Eneolithic individual, but rather a (Middle?) Bronze Age one, suggests that Sredni Stog was possibly not directly related to Corded Ware, and a potential direct connection with Yamnaya might have to be reevaluated, e.g. through the Carpathian Basin, as Anthony (2017) proposed.

pca-yamnaya-corded-ware-oblaczkowo
Principal component analysis of modern Europeans (grey) and projected ancient Europeans.

This new paper shows two early Corded Ware individuals from Obłaczkowo, Poland (ca. 2900-2600 BC) – hence close to the supposed original Proto-Corded Ware community – with an apparently (almost) full “Steppe-like” ancestry, clustering (almost) with Yamnaya individuals:

Similar to the BAC individuals, the newly sequenced individuals from the present-day Karlova in Estonia and Obłaczkowo in Poland appear to have strong genetic affinities to other individuals from BAC and CWC contexts across the Baltic Sea region. Some individuals from CWC contexts, including the two from Obłaczkowo, cluster closely with the potential source population of steppe-related ancestry, the Yamnaya herders. Notably, these individuals appear to be those with the earliest radiocarbon dates among all genetically investigated individuals from CWC contexts. Overall, for CWC-associated individuals, there is a clear trend of decreasing affinity to Yamnaya herders with time.

NOTE. Interestingly, this sample is almost certainly attributed to the skeleton E8-A, which had been supposedly already investigated by the Copenhagen group as the RISE1 sample:

We note that RISE1 is also described as the individual from Obłaczkowo feature E8-A. However, their genetic results differ from ours. They present this individual as a molecularly determined male that belongs to Y-chromosomal haplogroup (hg) R1b and to mtDNA hg K1b1a1 while our results show this individual to be female, carrying a mtDNA hg U3a’c profile

Since the typical Steppe_MLBA ancestry of Corded Ware groups does not show good fits for (Pre-)Yamnaya-derived ancestry, it is almost certain that these individuals will show no (or almost no) direct Yamnaya-related contribution, but rather a contribution of East European sub-Neolithic groups, more or less close to the steppe-forest region.

NOTE. They might show contributions from Pre-Yamnaya-influenced Sredni Stog, though, but if they show a contribution of Yamnaya, then they are probably outliers, related to Yamnaya vanguard groups (see image below). And for them to show it, then both sources, Yamnaya and Corded Ware, should be clearly distinguishable from each other and their relative contribution quantifiable in formal stats, something difficult (if not impossible) to ascertain today.

trypillian-yamnaya-influence-baltic
Trypillian routes of influence and Yamnaya culture influences in Central and Central-East Europe during the Late Eneolithic / Early Bronze Age. Images by Klochko (2009).

Their position in the published PCA – a plot apparently affected by projection bias – suggests a cluster in common with early Baltic samples, which are known to show contributions from East European sub-Neolithic populations (see qpAdm values for Baltic CWC samples).

NOTE. Results for previous samples labelled as Poland CWC are unreliable due to their low coverage.

The most interesting aspect about the ancestry shown by these early samples is their further support for an origin of the culture different than Sredni Stog, and for a rejection of the Alexandria outlier as ancestral to them, hence for a Volhynian-Podolian homeland of Proto-Corded Ware peoples, with an ancestry probably more closely related to the late Maykop Steppe- and Trypillian/GAC groups admixed with sub-Neolithic populations of the Eastern European Late Eneolithic.

NOTE. That is, unless there is a reason for the apparent increase in so-called “Steppe-ancestry” during the northward and westward migration of CWC peoples that represents another thing entirely…

#UPDATE (27 OCT 2019): Apparently, the PCA was actually not affected by projection bias:

Sample poz44 clusters ‘to the south’, with other early German ones, but also close to Yamnaya. Its poor coverage makes qpAdm results unreliable, but its common cluster close to central European and eastern CWC groups – despite belonging to the same Obłaczkowo site – supports that it is more representative of the Proto-CWC population than poz81.

Sample poz81 clusters with Yamnaya samples – or at least with the wider, Steppe-related cluster. Nevertheless, analyses with qpAdm – in combination with values obtained for other early Baltic samples – support that the ancestry of poz81 is more closely related to a core Corded Ware population admixed with sub-Neolithic peoples (similar to Samara LN).

NOTE. I have selected Czech CWC as a potential source closer to the Proto-CWC population, similar to models with Baltic samples. Since Czech CWC samples are later than these from Obłaczkowo, I have also checked the reverse model, with Poz81 and GAC Poland as a source for Czech CWC, and the fits are slightly worse. Anyway, ‘better’ or ‘worse’ p-values can’t determine the direction of migration

pca-corded-ware-poland-oblaczkowo-baltic-yamnaya
Detail of the PCA of Eurasian samples, including Corded Ware groups and related clusters, as well as outliers. Also marked is poz81.

I.2. CWC expansion under R1a bottlenecks

The two males in our dataset (ber1 and poz81) belonged to Y-chromosome R1a haplogroups, as do the majority of males (16/24) from the previously published CWC contexts, while a smaller fraction belonged to R1b [3/24] or I2a [3/24] lineages. The R1a haplogroup has not been found among Neolithic farmer populations nor in hunter–gatherer groups in central and western Europe, but it has been reported from eastern European hunter–gatherers and Eneolithic groups. Individuals from the Pontic–Caspian steppe, associated with the Yamnaya Culture, carry mostly R1b and not R1a haplotypes.

Sample poz81 is of basal hg. R1a-CTS4385*, an R1a-M417 subclade, supporting once again that most Corded Ware individuals from western and central European groups expanded under R1a-M417 (xZ645) lineages. The Battle Axe sample from Bergsgraven (ca. 2620-2470 BC) shows a basal hg. R1a-Y2395*, a R1a-Z283 subclade leading to the typically Fennoscandian R1a-Z284.

Both findings further support that typical lineages of West CWC groups, including R1a-M417 (xZ645) subclades, were fully replaced by incoming East Bell Beakers, and that the limited expansion of R1a-Z284 and I1 (the latter found in one newly reported Late Neolithic sample from Sweden) was the outcome of later regional bottlenecks within Scandinavia, after the creation of a maritime dominion by the Bell Beaker elites during the Dagger Period.

I.3. CWC and lactase persistence

(…) one of these individuals (kar1) carried at least one allele (-13910 C->T) associated with lactose tolerance, while the other two individuals (ber1 and poz81) carried at least one ancestral variant each, consistent with previous observations of low levels of lactose tolerance variants in the Neolithic and a slight increase among individuals from CWC contexts.

The fact that two early CWC individuals carry ancestral variants could be said to support the improbability of the individual from Alexandria representing a community ancestral to the Corded Ware community. On the other hand, the late CWC individual from Estonia carries one allele, but it still seems that only Bell Beakers and Steppe-related groups show the necessary two alleles during the Early Bronze Age, which is in line with a late Repin/early Yamnaya-related origin of the successful selection of the trait, consistent with the expansion of their specialized semi-nomadic cattle-breeding economy through the steppe biome during the Late Eneolithic.

rs4988235-lactase-persistence-history
Maps part of the public data used for the post by Iain Mathieson on Lactase Persistence. “By 2500 BP, the allele is present over a band stretching from Ireland to Central Asia at around 50 degrees latitude. This probably reflects the spread of Steppe ancestry populations in which the allele originated. However, the allele is still rare (say less than 1% frequency) over this entire range. It does not become common anywhere until some time in the past 2500 years – when it reaches its present-day high frequency in Britain and Central Europe”.

I.4. West Uralic spread from the East

The BAC groups fit as a sister group to the CWC-associated group from Estonia but not as a sister group to the CWC groups from Poland or Lithuania (|Z| > 3), indicating some differences in ancestry between these CWC groups and BAC. Supervised admixture modelling suggests that BAC may be the CWC-related group with the lowest YAM-related ancestry and with more ancestry from European Neolithic groups.

While the results of the paper are compatible with a migration from either the Eastern or the Western Baltic into Scandinavia, phylogeography and archaeology support that Battle Axe peoples emerged as a Baltic Corded Ware group close to the Vistula that expanded first to the north-east, and then to the west from Finland, continuing mostly unscathed during the whole Bronze Age mostly in eastern Fennoscandia with the development of Balto-Finnic- and Samic-speaking communities.

corded-ware-culture-ancestry-over-time
Correlation between f4(Chimp, LBK, YAM, X), where X is a CWC or BAC individual, and the date (BCE) of each individual. This statistic measures shared drift between CWC and Linear Pottery Culture (LBK) as opposed to YAM and should increase with the higher proportion of Neolithic farmer ancestry in CWC and BAC.

Radiocarbon dating showed that the three individuals from the Öllsjö megalithic tomb derived from later burials, where oll007 (2860–2500 cal BCE) overlaps with the time interval of the BAC, and oll009 and oll010 (1930–1650 cal BCE) fall within the Scandinavian Late Neolithic and Early Bronze Age

For more on how the Pitted Ware culture may have influenced Uralic-speaking Battle Axe peoples earlier than Indo-European-speaking Bell Beakers in Scandinavia, read more about Early Bronze Age Scandinavia and about the emergence of the Pre-Proto-Germanic community.

II. Bell Beakers through the Bronze Age

New paper (behind paywall) Kinship-based social inequality in Bronze Age Europe, by Mittnik et al. Science (2019).

II.1. Yamnaya vanguard settlers

In my last post, I showed how the ancestry of Corded Ware from Esperstedt is consistent with influence by incoming Yamnaya vanguard settlers or early Bell Beakers, stemming ultimately from the Carpathian Basin, something that could be inferred from the position of the Esperstedt outlier in the PCA, and by the knowledge of Yamnaya archaeological influences up to Saxony-Anhalt.

Yamnaya settlers are strongly suspected to have migrated in small so-called vanguard groups to the west and north of the Carpathians in the first half of the 3rd millennium BC, well before the eventual adoption of the Proto-Beaker package and their expansion ca. 2500 BC as East Bell Beakers.

Tauber Valley infiltration

As I mentioned in the books, one of the known – among the many more unknown – sites displaying Yamnaya-related traits and suggesting the expansion of Yamnaya settlers into Central Europe is Lauda-Königshofen, in the Tauber Valley.

From Diet and Mobility in the Corded Ware of Central Europe, by Sjögren, Price, & Kristiansen PLoS One (2017):

A series of CW cemeteries have been excavated in the Tauber valley. There are three large cemeteries known and some 30 smaller sites. The larger ones are Tauberbischofsheim-Dittingheim with 62 individuals, Tauberbischofsheim-Impfingen with 40 individuals, and Lauda-Königshofen with 91 individuals. The cemeteries are dispersed rather regularly along the Tauber valley, on both sides of the river, suggesting a quite densely settled landscape.

The Lauda-Königshofen graves consisted mostly of single inhumations in contracted position, usually oriented E-W or NE-SW. A total of 91 individuals were buried in 69 graves. At least 9 double graves and three graves with 3–4 individuals were present. In contrast to the common CW pattern, sexes were not distinguished by body position, only by grave goods. This trait is common in the Tauber valley and suggests a local burial tradition in this area. Stone axes were restricted to males, pottery to females, while other artifacts were common to both sexes. About a third of the graves were surrounded by ring ditches, suggesting palisade enclosures and possibly over-plowed barrows.

In particular, Frînculeasa, Preda, & Heyd (2015) used Lauda-Königshofen as representative of the mobility of horse-riding Yamnaya nomadic herders migrating into southern Germany, referring to the findings in Trautmann (2012) about the nomadic herders from the Tauber Valley, and their already known differences with other Corded Ware groups.

The likely influence of Yamnaya in the region has been reported at least since the 2000s, repeatedly mentioned by Jozef Bátora (2002, 2003, 2006), who compiled Yamnaya influences in a map that has been copied ever since, with little improvement over time. Heyd believes that there are potentially many Yamnaya remains along the Middle and Lower Danube and tributaries not yet found, though.

NOTE. Looking for this specific site, I realized that Bátora (and possibly many after him who, like me, copied his map) located Lauda-Königshofen in a more south-western position within Baden-Württemberg than its actual location. I have now corrected it in the maps of Chalcolithic migrations.

yamnaya-corded-ware-europe
Yamnaya influences in Central Europe suggestive of vanguard settlements, contemporary with Corded Ware groups. See full map.

Althäuser Hockergrab…Bell Beakers

Unfortunately, though, it is very difficult to attribute the reported R1b-L51 sample from the Tauber valley to a population preceding the arrival of East Bell Beakers in the region, so there is no uncontroversial smoking gun of Yamnaya vanguard settlers – yet. Reasons to doubt a Pre-Beaker origin are as follows:

1. This family of the Tauber valley shows a late radiocarbon date (ca. 2500 BC), i.e. from a time where East Bell Beakers are known to have been already expanding in all directions from the Middle and Upper Danube and its tributaries.

tauber-valley-althauser-hockergrab
Crouched burial from Althausen (Althäuser Hockergrab), dated ca. 2500 BC.

2. Archaeological information is scarce. Remains of these four individuals were discovered in 1939 and officially reported together with other findings in 1950, without any meaningful data that could distinguish between Bell Beakers and Corded Ware individuals.

This site is located in the Tauber valley, ca. 100 km to the northwest of the Lech valley. The site was discovered during the construction of a sports field in 1939 and was subsequently excavated by G. Müller and O. Paret. Four individuals in crouched position were found in the burial pit of a flat grave. The burial did not contain any grave goods, but due to the type of grave and positioning of the bodies (with heads pointing towards southwest) the site was attributed to the Corded Ware complex.

The classification of this burial as of CWC and not BBC seems to have been based entirely on the numerous CWC findings in the Tauber valley, rather than on its particular burial orientation following a regional custom (foreign to the described standard of both cultures), and on its grave type that was also found among Bell Beaker groups. Like many human remains recovered in dubious circumstances in the 20th century, these samples should have probably been labelled (at least in the genetic paper) more properly as Tauber_LN or Tauber_EBA.

yamnaya-bias-tauber-lech-valley
Changes in ancestry over time. (A) Median ages of individuals plotted against z scores of f4 (Mbuti, Test; Yamnaya_Samara, Anatolia_Neolithic) show increase of Anatolian farmer-related ancestry (indicated by more positive z-scores) and decrease of variation in ancestry over time. Grey shading indicates significant z scores, red line shonw near correlation (r = -0.35971; P = 0.003) and dotted lines the 95% confidence interval. (B) ancestry proportions on autosomes calculated with qpAdm. (C) Sex-bias z scores between autosomes and X chromosomes show significant male bias for steppe-related ancestry in the Tauber samples. Image modified from the paper: Surrounded with a blue circle in (A) are females with more Steppe-related ancestry, and in (C) surrounded by squares are the distinct sex biases found in the earliest BBC from the Tauber valley vs. later groups from the Lech valley.

3. In terms of ancestry, there seem to be no gross differences between the Lech Valley BBC individuals and previously reported South German Beakers, originally Yamnaya-like settlers admixing through exogamy with locals, including Corded Ware peoples, as the sex bias of the Lech Valley Beakers proves (see PCA plot below). In other words, northern and eastern Beakers admixed with regional (Epi-)Corded Ware females during their respective expansions, similar to how southern and western Beakers admixed with regional EEF-related females.

The two available Tauber Valley samples (“Tauber_CWC”) show the same pattern: a quite recent Steppe-related male bias and Anatolia_Neolithic-related female bias. Nevertheless, the male sample clusters ‘to the south’ in the PCA relative to all sampled Corded Ware individuals (see PCA plot below), and shows less Yamnaya-like ancestry than what is reported (or can be inferred) for Yamnaya from Hungary or early Bell Beakers of elevated Steppe-related ancestry.

yamnaya-ancestry-tauber-cwc-bbc-lech-eba-mba
Table S9. Three-way qpAdm admixture model for European MN/Chalcolithic group+Yamnaya_Samara. P-values greater than 0.05 (model is not rejected) marked in green.

The ancestry and position of the Althäuser male in the PCA is thus fully compatible with recently incoming East Bell Beakers admixing with local peoples (including Corded Ware) through exogamy, but not so much with a sample that would be expected from Yamanaya vanguard + Corded Ware-related ancestry (more like the Esperstedt outlier or the early France Beaker). Compared to the more ‘northern’ (fully Corded Ware-like) position ancestry of his female counterpart, there is little to support that both are part of the same native Tauber valley community after generations of ancestry levelling…

#UPDATE (27 OCT 2019): The PCA shows that the Althäuser male clusters, in fact, ‘to the north’ of the female one, almost on the same spot as a Bell Beaker sample from the Lech Valley.

Despite their reported damage and poor coverage, there seems to be a trend for qpAdm values to prefer a source population for the male (Alt_4) close to Germany Beakers, whereas the female sample (Alt_3) shows ‘better’ fits when a Corded Ware source is selected.

Also relevant is the Corded Ware ancestry of the male – closer to a Czech rather than German CWC source – compatible with an eastern origin, hence supporting a recent arrival via the Danube, in contrast to the local source of the CWC admixture of the female. The poorer coverage of the female sample makes these results questionable, though.

pca-bell-beaker-tauber-lech-valley-yamnaya-cwc
Detail of the PCA of Eurasian samples, including Bell Beaker groups and related clusters, as well as outliers. Also marked are the Tauber Valley male (M) and female (F).

4. The haplogroup inference is also unrevealing: whereas the paper reports that it is R1b-P310* (xU106, xP312), there is no data to support a xP312 call, so it may well be even within the P312 branch, like most sampled Bell Beaker males. Similarly, the paper also reports that HUGO_180Sk1 (ca. 2340 BC) shows a positive SNP for the U106 trunk, which would make it the earliest known U106 sample and originally from Central Europe, but there is no clear support for this SNP call, either. At least not in their downloadable BAM files, as far as I can tell. Even if both were true, they would merely confirm the path of expansion of Yamnaya / East Bell Beakers through the Danube, already visible in confirmed genomic data:

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

II.2. Proto-Celts and the Tumulus culture

The most interesting data from Mittnik et al. (2019) – overshadowed by the (at first sight) striking “CWC” label of the Althäuser male – is the finding that the most likely (Pre-)Proto-Celtic community of Southern Germany shows, as expected, major genetic continuity over time with Yamnaya/East Bell Beaker-derived patrilineal families, which suggests an almost full replacement of other Y-chromosome haplogroups in Southern German Bronze Age communities, too.

Sampled families form part of an evolving Bell Beaker-derived European BA cluster in common with other Indo-European-speaking cultures from Western, Southern, and Northern Europe, also including early Balto-Slavs, clearly distinct from the Corded Ware-related clusters surviving in the Eastern Baltic and the forest zone.

This Central European Bronze Age continuity is particularly visible in many generations of different patrilocal families practising female exogamy, showing patrilineal inheritance mainly under R1b-P312 (mostly U152+) lineages proper of Central European bottlenecks, all of them apparently following a similar sociopolitical system spanning roughly a thousand years, since the arrival of East Bell Beakers in the region (ca. 2500 BC) until – at least – the end of the Middle Bronze Age (ca. 1300 BC):

Here, we show a different kind of social inequality in prehistory, i.e., complex households that consisted of i) a higher-status core family, passing on wealth and status to descendants, ii) unrelated, wealthy and high-status non-local women and iii) local, low-status individuals. Based on comparisons of grave goods, several of the high-status non-local females could have come from areas inhabited by the Unetice culture, i.e., from a distance of at least 350 km. As the EBA evidence from most of Southern Germany is very similar to the Lech valley, we suggest that social structures comparable to our microregion existed in a much broader area. The EBA households in the Lech valley, however, seem similar to the later historically known oikos, the household sphere of classic Greece, as well as the Roman familia, both comprising the kin-related family and their slaves.

pca-lech-valley-bell-beaker-eba
Genetic structure of Late Neolithic and Bronze Age individuals from southern Germany. (A) Ancient individuals (covered at 20,000 or more SNPs) projected onto principal components defined by 1129 present day west Eurasians (shown in fig. S6); individuals in this study shown with outlines corresponding to their 87Sr/86Sr isotope value (black: consistent with local values, orange: uncertain/intermediate, red: inconsistent with local values). Selected published ancient European individuals are shown without outlines. Image modified from the paper. Surrounded by triangles in cyan, Corded Ware-like females; with a blue triangle, Yamnaya/Early BBC-like sample from the Tauber valley.

NOTE. For those unfamiliar with the usual clusters formed by the different populations in the PCA, you can check similar graphics: PCA with Bell Beaker communities, PCA with Yamnaya settlers from the Carpathians, a similar one from Wang et al. (2019) showing the Yamnaya-Hungary cline, or the chronological PCAs prepared by me for the books.

The gradual increase in local EEF-like ancestry among South Germany EBA and MBA communities over the previous BBC period offers a reasonable explanation as to how Italic and Celtic communities remained in loose contact (enough to share certain innovations) despite their physical separation by the Alps during the Early Bronze Age, and probably why sampled Bell Beakers from France were found to be the closest source of Celts arriving in Iberia during the Urnfield period.

Furthermore, continued contacts with Únětice-related peoples through exogamy also show how Celtic-speaking communities closer to the Danube might have influenced (and might have been influenced by) Germanic-speaking communities of the Nordic Late Neolithic and Bronze Age, helping explain their potentially long-lasting linguistic exchange.

Like other previous Neolithic or Chalcolithic groups that Yamnaya and Bell Beakers encountered in Europe, ancestry related to the Corded Ware culture became part of Bell Beaker groups during their expansion and later during the ancestry levelling in the European Early Bronze Age, which helps us distinguish the evolution of Indo-European-speaking communities in Europe, and suggests likely contacts between different cultural groups separated hundreds of km. from each other.

All in all, there is nothing to support that (epi-)Corded Ware groups might have survived in any way in Central or Western Europe: whether through their culture, their Y-chromosome haplogroups, or their ancestry, they followed the fate of other rapidly expanding groups before them, viz. Funnelbeaker, Baden, or Globular Amphorae cultural groups. This is very much unlike the West Uralic-speaking territory in the Eastern Baltic and the Russian forests, where Corded Ware-related cultures thrived during the Bronze Age.

lech-valley-yamnaya-ancestry-over-time
f4-statistics showing differences in ancestry in populations grouped by period. An increase in affinity to ancestry related to Anatolia Neolithic over time. Males and females grouped together shown as upward and downward pointing triangles, respectively.

Conclusion

It was about time that geneticists caught up with the relevance of Y-DNA bottlenecks when assessing migrations and cultural developments.

From Malmström et al. (2019):

The paternal lineages found in the BAC/CWC individuals remain enigmatic. The majority of individuals from CWC contexts that have been genetically investigated this far for the Y-chromosome belong to Y-haplogroup R1a, while the majority of sequenced individuals of the presumed source population of Yamnaya steppe herders belong to R1b. R1a has been found in Mesolithic and Neolithic Ukraine. This opens the possibility that the Yamnaya and CWC complexes may have been structured in terms of paternal lineages—possibly due to patrilineal inheritance systems in the societies — and that genetic studies have not yet targeted the direct sources of the expansions into central and northern Europe.

From Gibbons (2019), a commentary to Mittnik et al. (2019):

Some of the early farmers studied were part of the Neolithic Bell Beaker culture, named for the shape of their pots. Later generations of Bronze Age men who retained Bell Beaker DNA were high-ranking, buried with bronze and copper daggers, axes, and chisels. Those men carried a Y chromosome variant that is still common today in Europe. In contrast, low-ranking men without grave goods had different Y chromosomes, showing a different ancestry on their fathers’ side, and suggesting that men with Bell Beaker ancestry were richer and had more sons, whose genes persist to the present.

There was no sign of these women’s daughters in the burials, suggesting they, too, were sent away for marriage, in a pattern that persisted for 700 years. The only local women were girls from high-status families who died before ages 15 to 17, and poor, unrelated women without grave goods, probably servants, Mittnik says. Strontium levels from three men, in contrast, showed that although they had left the valley as teens, they returned as adults.

Also, from Scientific American:

(…) it has long been assumed that prior to the Athenian and Roman empires,—which arose nearly 2,500 and more than 2,000 years ago, respectively—human social structure was relatively straightforward: you had those who were in power and those who were not. A study published Thursday in Science suggests it was not that simple. As far back as 4,000 years ago, at the beginning of the Bronze Age and long before Julius Caesar presided over the Forum, human families of varying status levels had quite intimate relationships. Elites lived together with those of lower social classes and women who migrated in from outside communities. It appears early human societies operated in a complex, class-based system that propagated through generations.

It seems wrong (to me, at least) that the author and – as he believes – archaeologists and historians had “assumed” a different social system for the European Bronze Age, which means they hadn’t read about how Indo-European societies were structured. For example, long ago Benveniste (1969) already drew some coherent picture of these prehistoric peoples based on their reconstructed language alone: regarding their patrilocal and patrilineal family system; regarding their customs of female exogamy and marriage system; and regarding the status of foreigners and slaves as movable property in their society.

A long-lasting and pervasive social system of Bronze Age elites under Yamnaya lineages strikingly similar to this Southern German region can be easily assumed for the British Isles and Iberia, and it is likely to be also found in the Low Countries, Northern Germany, Denmark, Italy, France, Bohemia and Moravia, etc., but also (with some nuances) in Southern Scandinavia and Central-East Europe during the Bronze Age.

Therefore, only the modern genetic pool of some border North-West Indo-European-speaking communities of Europe need further information to describe a precise chain of events before their eventual expansion in more recent times:

  1. the relative geographical isolation causing the visible regional founder effects in Scandinavia, proper of the maritime dominion of the Nordic Late Neolithic (related thus to the Island Biogeography Theory); and
  2. the situation of the (Pre-)Proto-Balto-Slavic community close to the Western Baltic which, I imagine, will be shown to be related to a resurge of local lineages, possibly due to a shift of power structures similar to the case described for Babia Góra.

NOTE. Rumour has it that R1b-L23 lineages have already been found among Mycenaeans, while they haven’t been found among sampled early West European Corded Ware groups, so the westward expansion of Indo-European-speaking Yamnaya-derived peoples mainly with R1b-L23 lineages through the Danube Basin merely lacks official confirmation.

Related

Bell Beakers and Mycenaeans from Yamnaya; Corded Ware from the forest steppe

eba-yamnaya-ancestry-hungary

I have recently written about the spread of Pre-Yamnaya or Yamnaya ancestry and Corded Ware-related ancestry throughout Eurasia, using exclusively analyses published by professional geneticists, and filling in the gaps and contradictory data with the most reasonable interpretations. I did so consciously, to avoid any suspicion that I was interspersing my own data or cherry picking results.

Now I’m finished recapitulating the known public data, and the only way forward is the assessment of these populations using the available datasets and free tools.

Understanding the complexities of qpAdm is fairly difficult without a proper genetic and statistical background, which I won’t pretend to have, so its tweaking to get strictly correct results would require an unending game of trial and error. I have sadly little time for this, even taking my tendency to procrastination into account… so I have used a simple model akin to those published before – in particular, the outgroup selection by Ning, Wang et al. (2019), who seem to be part of the only group interested in distinguishing Yamnaya-related from Corded Ware-related ancestry, probably the most relevant question discussed today in population genomics regarding the Proto-Indo-European and Proto-Uralic homelands.

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.

I have used for all analyses below a merged dataset including the curated one of the Reich Lab, the latest on Central and South Asia by Narasimhan, Patterson et al. (2019), on Iberia by Olalde et al. (2019), and on the East Baltic by Saag et al. (2019), as well as datasets including samples from Wang et al. (2019) and Lamnidis et al. (2018). I used (and intend to use) the same merged dataset in all cases, despite its huge size, to avoid adding one more uncontrolled variable to the analyses, so that all results obtained can be compared.

I try to prepare in advance a bunch of relevant files with left pops and right pops for each model:

  1. It seems a priori more reasonable to use geographically and chronologically closer proxy populations (say, Trypillia or GAC for Steppe-related peoples) than hypothetic combinations of ancestral ones (viz. Anatolian farmer, WHG, and EHG).
  2. This also means using subgroups closer to the most likely source population, such as (Don-Volga interfluve) Yamnaya_Kalmykia rather than (Middle Volga) Yamnaya_Samara for the western expansion of late Repin/early Yamnaya, or the early Germany_Corded_Ware.SG or Czech_Corded Ware for the group closest to the Proto-Corded Ware population (see below), likely neighbouring the Upper Vistula region.
  3. I usually test two source populations for different targets, which seems like a much more efficient way of using computer resources, whenever I know what I want to test, since I need my PC back for its normal use; whenever I don’t know exactly what to test, I use three-way admixture models and look for subsets to try and improve the results.

I have probably left out some more complex models by individualizing the most relevant groups, but for the time being this would have to do. Also, no other formal stats have been used in any case, which is an evident shortcoming, ruling out an interpretation drawn directly and only from the results below.

Full qpAdm results for each batch of samples are presented in a Google Spreadsheet, with each tab (bottom of the page) showing a different combination of sources, usually in order of formally ‘best’ (first to the left) to ‘worst’ (last to the right) fits, although the order is difficult to select in highly heterogeneous target groups, as will be readily visible.

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).

Corded Ware origins

The latest publications on the Yampil barrow complex have not improved much our understanding of the complexity of Corded Ware origins from an archaeological point of view, involving multiple cultural (hence likely population) influences. This bit is from Ivanova et al., Baltic-Pontic Studies (2015) 20:1, and most hypotheses of the paper remain unanswered (except maybe for the relevance of the Złota group):

In the light of the above outline therefore one should argue that the ‘architecture of barrows’ associated in the ‘Yampil landscape’ of the Middle Dniester Area with the Eneolithic (specifically, mainly with the TC), precedes the development of a similar phenomenon that can be observed from 2900/2800 BC in the Upper Dniester Area and drainage basin of the Upper Vistula, associated with the CWC [Goslar et al. 2015; Włodarczak 2006; 2007; 2008; Jarosz, Włodarczak 2007]. The most consuming research question therefore is whether ritual customs making use of Eneolithic (Tripolye) ‘barrow architecture’ could have penetrated northwards along the Dniester route, where GAC communities functioned. One could also ask what role the rituals played among the autochthons [Kośko 2000; Włodarczak 2008; 2014: 335; Ivanova, Toshchev 2015b].

This issue has already been discussed with a resulting tentative systemic taxonomy in the studies of Włodarczak, arguing for the Złota culture (ZC) in the Vistula region as an illustration of one of the (Małopolska) reception centres of civilization inspirations from the oldest Pontic ‘barrow culture’ circle associated with the Eneolithic and Early Bronze Age [Włodarczak 2008]. Notably, it is in the ZC that one can notice a set of cultural traits (catacomb grave construction, burial details, forms and decoration of vessels) analogous to those shared by the north-western Black Sea Coast groups of the forest-steppe Eneolithic (chiefly Zhyvotilovka-Volchansk) and the Late Tripolye circle (chiefly Usatovo-Gordinești-Horodiștea-Kasperovtsy).

gac-trypillia-usatovo-corded-ware
Globular Amphorae culture „exodus” to the Danube Delta: a – Globular Amphorae culture; b – GAC (1), Gorodsk (2), Vykhvatintsy (3) and Usatovo (4) groups of Trypillia culture; c – Coţofeni culture; d – northern border of the late phase of Baden culture;red arrows – direction of Globular Amphora culture expansion; blue arrow – direction of „reflux” of Globular Amphora culture (apud Włodarczak, 2008, with changes).

Taking into account that I6561 might be wrongly dated, we cannot include the Corded Ware-like sample of the end-5th millennium BC in the analysis of Corded Ware origins. That uncertainty in the chronology of the appearance of “Steppe ancestry” in Proto-Corded Ware peoples complicates the selection of any potential source population from the CHG cline.

Nevertheless, the lack of hg. R1a-M417 and sizeable Pre-Yamnaya-related ancestry in the sampled Pontic forest-steppe Eneolithic populations (represented exclusively by two samples from Dereivka ca. 3600-3400 BC) would leave open the interesting possibility that a similar ancestry got to the forest-steppe region between modern Poland and Ukraine during the known complex population movements of the Late Eneolithic.

It is known that Corded Ware-derived groups and Steppe Maykop show bad fits for Pre-Yamnaya/Yamnaya ancestry, and also that Steppe Maykop is a potential source of “Steppe-related ancestry” within the Eneolithic CHG mating network of the Pontic-Caspian steppes and forest-steppes. Testing Corded Ware for recent Trypillia and Maykop influences, proper of Late Trypillia and Late Maykop groups in the North Pontic area (such as Zhyvotylivka–Vovchans’k and Gordineşti) side by side with potential Pre-Yamnaya and Yamnaya sources makes thus sense:

Now, the main obvious difference between Khvalynsk-Yamnaya and Corded Ware is the long-lasting, pervasive Y-chromosome bottlenecks under R1b lineages in the former, compared to the haplogroup variability and late bottleneck under R1a-M417 in the latter, which speaks in favour – on top of everything else – of a different community of sub-Neolithic hunter-gatherers including hg. R1a-M417 hijacking the expansion of Steppe_Maykop-related ancestry around the Volhynian-Podolian Upland.

Akin to how Yamnaya patrilineal descendants hijacked regional EEF (±CWC) ancestry components mainly through exogamy, dragging them into the different expanding Bell Beaker groups (see below), but kept their Indo-European languages, these hunter-gatherers that admixed with peoples of “Steppe ancestry” were the most likely vector of expansion of Uralic languages in Eastern Europe.

corded-ware-from-trypillia-maykop
PCA of ancient Eurasian samples. Marked likely Proto-Corded Ware samples and potential origin of its PCA cluster based on qpAdm results. See full PCA and more related files.

Baltic Corded Ware

One of the most interesting aspects of the results above is the surprising heterogeneity of the different regional groups, which is also reflected in the Y-DNA variability of early Corded Ware samples.

Seeing how Baltic CWC groups, especially the early Latvia_LN sample, show particularly bad fits with the models above, it seems necessary to test how this population might have come to be. My first impression in 2017 was that they could represent early Corded Ware groups admixed with Yamnaya settlers through their interactions along the Dnieper-Dniester corridor.

However, I recently predicted that the most likely admixture leading to their ancestry and PCA cluster would involve a Corded Ware-like group and a group related to sub-Neolithic cultures of eastern Europe, whose best proxy to date are EHG-like Khvalynsk samples (i.e. excluding the outlier with Pre-Yamnaya ancestry, I0434):

corded-ware-pca-sub-neolithic-europe
Detail of the PCA of the Corded Ware expansion. See full PCA and more related files.

Late Corded Ware + Yamnaya vanguard

Relevant are also the mixtures of Corded Ware from Esperstedt, and particularly those of the sample I0104, which I have repeated many times in this blog I suspected to be influenced by vanguard Yamnaya settlers:

The infeasible models of CWC + Yamnaya_Kalmykia ± Hungary_Baden (see below for Bell Beakers) and the potential cluster formed with other samples from the Baltic suggest that it could represent a more complex set of mixtures with sub-Neolithic populations. On the other hand, its location in Germany, late date (ca. 2500 BC or later), and position in the PCA, together with the good fits obtained for Germany_Beaker as a source, suggest that the increase in Steppe-related ancestry + EEF makes it impossible for the model (as I set it) to directly include Yamnaya_Kalmykia, despite this excess Steppe-related ancestry actually coming from Yamnaya vanguard groups.

I think it is very likely that the future publication of EEF-admixed Yamnaya_Hungary samples (or maybe even Yamnaya vanguard samples) will improve the fits of this model.

These results confirm at least the need to distrust the common interpretation of mixtures including late Corded Ware samples from Esperstedt (giving rise to the “up to 75% Yamnaya ancestry of CWC” in the 2015 papers) as representative of the Corded Ware culture as a whole, and to keep always in mind that an admixture of European BA groups including Corded Ware Esperstedt as a source also includes East BBC-like ancestry, unless proven otherwise.

yamnaya-vanguard-corded-ware-chalcolithic-early
Yamnaya vanguard groups in Corded Ware territory before the expansion of Bell Beakers (ca. 2500 BC). See full map.

Bell Beaker expansion

A hotly (re)debated topic in the past 6 months or so, and for all the wrong reasons, is the origin of the Bell Beaker folk. Archaeology, linguistics, and different Y-chromosome bottlenecks clearly indicate that Bell Beakers were at the origin of the North-West Indo-European expansion in Europe, while the survival of Corded Ware-related groups in north-eastern Europe is clearly related to the expansion of Uralic languages.

NOTE. For the interesting case of Proto-Indo-Iranians expanding with Corded Ware-like ancestry, see more on the formation of Sintashta-Potapovka-Filatovka from East Uralic-speaking Abashevo and Pre-Proto-Indo-Iranian-speaking Poltavka herders. See also more on R1a in Indo-Iranians and on the social complexity of Sintashta.

Nevertheless, every single discarded theory out there seems to keep coming back to life from time to time, and a new wave of interest in “Bell Beaker from the Single Grave culture” somehow got revived in the process, too, because this obsession – unlike the “Bell Beakers from Iberia Chalcolithic” – is apparently acceptable in certain circles, for some reason.

We know that Iberian Beakers, British Beakers, or Sicilian EBA – representing the most likely closest source population of speakers of Proto-Galaico-Lusitanian, Pre-Celtic Indo-European, and Proto-Elymian, respectively – have already been successfully tested for a direct origin among Western European Beakers in Olalde et al. (2018), Olalde et al. (2019), and Fernandes et al. (2019).

This success in ascertaining a closer Beaker source is probably due to the physical isolation of the specific groups (related to Germany_Beaker, Netherlands_Beaker, and NE_Mediterranean_Beaker samples, respectively) after their migration into regions dominated by peoples without Steppe-related ancestry. Furthermore, Celtic-speaking populations expanding with Urnfield south of the Pyrenees also show a good fit with a source close to France_Beaker.

So I decided to test sampled Bell Beaker populations, to see if it could shed light to the most likely source population of individual Beaker groups and the direction of migration within Central Europe, i.e. roughly eastwards or westwards. As it was to be expected for closely related populations (see the relevant discussion here), an attempt to offer a simplistic analysis of direction based on formal stats does not make any sense, because most of the alternative hypotheses cannot be rejected:

Not only because of the similar values obtained, but because it is absurd to take p-values as a measure of anything, especially when most of these conflicting groups with slightly ‘better’ or ‘worse’ p-values represent multiple different mixtures of the type (Yamnaya + EEF) + (Corded Ware + EEF ± Yamnaya), impossible to distinguish without selecting proper, direct ancestral populations…

A further example of how explosive the Bell Beaker expansion was into different territories, and of their extensive local admixture, is shown by the unsuccessful attempt by Olalde et al. (2018) to obtain an origin of the EEF source for all Beaker groups (excluding Iberian Beakers):

bell-beaker-local-population-iberia
Investigating the genetic makeup of Beaker-complex-associated individuals. Testing different populations as a source for the Neolithic ancestry component in Beaker-complex-associated individuals. The table shows P values (* indicates values > 0.05) for the fit of the model: ‘Steppe_EBA + Neolithic/Copper Age’ source population.
burials-yamnaya-hungary
Map of attested Yamnaya pit-grave burials in the Hungarian plains; superimposed in shades of blue are common areas covered by floods before the extensive controls imposed in the 19th century; in orange, cumulative thickness of sand, unfavourable loamy sand layer. Marked are settlements/findings of Boleráz (ca. 3500 BC on), Baden (until ca. 2800 BC), Kostolac (precise dates unknown), and Yamna kurgans (from ca. 3100/3000 BC on).

Now, there is a simpler way to understand what kind of Steppe-related ancestry is proper of Bell Beakers. I tested two simple models for some Beaker groups: Yamnaya + Hungary Baden vs. Corded Ware + GAC Poland. After all, the Bell Beaker folk should prefer a source more closely related to either Yamnaya Hungary or Central European Corded Ware:

Interestingly, models including Yamnaya + Baden show good fits for the most important groups related to North-West Indo-Europeans, including Bell Beakers from Germany, the Netherlands, Italy, and Poland, representing the most likely closest source populations of speakers of Pre-Proto-Celtic, Pre-Proto-Germanic, Proto-Italo-Venetic, and Pre-Proto-Balto-Slavic, respectively.

The admixed Yamnaya samples from Hungary that will hopefully be published soon by the Jena Lab will most likely further improve these fits, especially in combination with intermediate Chalcolithic populations of the Middle and Upper Danube and its tributaries, to a point where there will be an absolute chronological and geographical genomic trail from the fully Yamnaya-like Yamnaya settlers from Hungary to all North-West Indo-European-speaking groups of the Early Bronze Age.

The only difference between groups will be the gradual admixture events of their source Beaker group with local populations on their expansion paths, including peoples of mainly EEF, CWC+EEF, or CWC+EEF+Yamnaya related ancestry. There is ample evidence beyond ancestry models to support this, in particular continued Y-DNA bottlenecks under typical Yamnaya paternal lineages, mainly represented by R1b-L51 subclades.

east-bell-beaker-group-expansion
Distribution of the Bell Beaker East Group, with its regional provinces, as of c. 2400 cal BC (after Heyd et al. 2004, modified). See full maps.

European Early Bronze Age

European EBA groups that might show conflicting results due to multiple admixture events with Corded Ware-related populations are the Únětice culture and the Nordic Late Neolithic.

The results for Únětice groups seem to be in line with what is expected of a Central European EBA population derived from Bell Beakers admixed with surrounding poulations of East Bell Beaker and/or late (Epi-)Corded Ware descent.

Potential models of mixture for Nordic Late Neolithic samples – despite the bad fits due to the lack of direct ancestral CWC and BBC groups from Denmark – seem to be impossible to justify as derived exclusively from Single Grave or (even less) from Battle Axe peoples, supporting immigration waves of Bell Beakers from the south and further admixture events with local groups through maritime domination.

PCA of ancient European samples. Marked are Bronze Age clusters. See full PCAs.

Balkans Bronze Age

The potential origin of the typical Corded Ware Steppe-related ancestry in the social upheaval and population movements of the Dnieper-Dniester forest-steppe corridor during the 4th millennium BC raises the question: how much do Balkan Bronze Age groups owe their ancestry to a population different than the spread of Pre-Yamnaya-like Suvorovo-Novodanilovka chieftains? Furthermore, which Bronze Age groups seem to be more likely derived exclusively from Pre-Yamnaya groups, and which are more likely to be derived from a mixture of Yamnaya and Pre-Yamnaya? Do the formal stats obtained correspond to the expected results for each group?

Since the expansion of hg. I2a-L699 (TMRCA ca. 5500 BC) need not be associated with Yamnaya, some of these values – together with the assessment of each individual archaeological culture – may question their origin in a Yamnaya-related expansion rather than in a Khvalynsk-related one.

NOTE. These are the last ones I was able to test yesterday, and I have not thought these models through, so feel free to propose other source and target groups. In particular, complex movements through the North Pontic area during the Late Eneolithic would suggest that there might have been different Steppe-ancestry-related vs. EEF-related interactions in the north-west and west Pontic area before and during the expansion of Yamnaya.

Mycenaeans

One of the key Indo-European populations that should be derived from Yamnaya to confirm the Steppe hypothesis, together with North-West Indo-Europeans, are Proto-Greeks, who will in turn improve our understanding of the preceding Palaeo-Balkan community. Unfortunately, we only have Mycenaean samples from the Aegean, with slight contributions of Steppe-related ancestry.

Still, analyses with potential source populations for this Steppe ancestry show that the Yamnaya outlier from Bulgaria is a good fit:

The comparison of all results makes it quite evident the why of the good fits from (Srubnaya-related) Bulgaria_MLBA I2163 or of Sintashta_MLBA relative to the only a priori reasonable Yamnaya and Catacomb sources: it is not about some hypothetical shared ancestor in Graeco-Aryan-speaking East Yamnaya– or even Catacomb-Poltavka-related groups, because all available Yamnaya-related peoples are almost indistinguishable from each other (at least with the sampling available today). These results reflect a sizeable contribution of similar EEF-related populations from around the Carpathians in both Steppe-related groups: Corded Ware and Yamnaya settlers from the Balkans.

mycenaeans-minyan-ware-greece-minoan
Cultural groups in and around the Balkans during the Early Bronze Age. See full maps.

qpAdm magic

In hobby ancestry magic, as in magic in general, it is not about getting dubious results out of thin air: misdirection is the key. A magician needs to draw the audience attention to ‘remarkable’ ancestry percentages coupled with ‘great’ (?) p-values that purportedly “prove” what the audience expects to see, distracting everyone from the true interesting aspects, like statistical design, the data used (and its shortcomings), other opposing models, a comparison of values, a proper interpretation…you name it.

I reckon – based on the examples above – that the following problems lie at the core of bad uses of qpAdm:

  1. In the formal aspect, the poor understanding of what p-values and other formal stats obtained actually mean, and – more importantly – what they don’t mean. The simplistic trend to accept results of a few analyses at face value is necessarily wrong, in so far as there is often no proper reasoning of what is being assessed and how, and there is never a previous opinion about what could be expected if the alternative hypotheses were true.
  2. In the interpretation aspect, the poor judgement of accompanying any results with simplistic, superficial, irrelevant, and often plainly wrong archaeological or linguistic data selected a posteriori; the inclusion of some racial or sociopolitical overtones in the mixture to set a propitious mood in the target audience; and a sort of ritualistic theatrics with the main theme of ‘winning’, that is best completed with ad hominems.

If you get rid of all this, the most reasonable interpretation of the output of a model proposed and tested should be similar to Nick Patterson’s words in his explanation of qpWave and qpAdm use:

Here we see that, at least in this analysis there are reasonable models with CordedWareNeolithic is a mix of either WHG or LBKNeolithic and YamnayaEBA. (…) The point of this note is not to give a serious phylogenetic analysis but the results here certainly support a major Steppe contribution to the Corded Ware population, which is entirely concordant with the archaeology [?].

Very far, as you can see, from the childish “Eureka! I proved the source!”-kind of thinking common among hobbyists.

The Mycenaean case is an illustrative example: if the Yamnaya outlier from Bulgaria were not available, and if one were not careful when designing and assessing those mixture models, the interpretation would range from erroneous (viz. a Graeco-Aryan substrate, as I initially thought) to impossible (say, inventing migration waves of Sintashta or Srubnaya peoples into Crete). The models presented above show that a contribution of Yamnaya to Mycenaeans couldn’t be rejected, and this alone should have been enough to accept Yamnaya as the most likely source population of “Steppe ancestry” in Proto-Greeks, pending intermediate samples from the Balkans. In other words, one could actually find that ‘the best’ p-values for source populations of Mycenaeans is a combination of modern Poles + Turks, despite the impracticality of such a model…

I haven’t been able to reproduce results which supposedly showed that Corded Ware is more likely to be derived from (Pre-)Yamnaya than other source population, or that Corded Ware is better suited as the ancestral population of Bell Beakers. The analyses above show values in line with what has been published in recent scientific papers, and what should be expected based on linguistics and archaeology. So I’ll go out on a limb here and say that it’s only through a careful selection of outgroups and samples tested, and of as few compared models as possible, that you could eventually get this kind of results and interpretation, if at all.

Whether that kind of special care for outgroups and samples is about (a) an acceptable fine-tuning of the analyses, (b) a simplistic selection dragged from the first papers published and applied indiscriminately to all models, or (c) cherry picking analyses until results fit the expected outcome, is a question that will become mostly irrelevant when future publications continue to support an origin of the expansion of ancient Indo-European languages in Khvalynsk- and Yamnaya-related migrations.

Feel free to suggest (reasonable) modifications to correct some of these models in the comments. Also, be sure to check out other values such as proportions, SD or SNPs of the different results that I might have not taken into account when assessing ‘good’ or ‘bad’ fits.

Related

On the Ukraine Eneolithic outlier I6561 from Alexandria

sredni-stog-eneolithic-late

Over the past week or so, since the publication of new Corded Ware samples in Narasimhan, Patterson et al. (2019) and after finding out that the R1a-M417 star-like phylogeny may have started ca. 3000 BC, I have been ruminating the relevance of contradictory data about the Ukraine_Eneolithic_o sample from Alexandria, its potential wrong radiocarbon date, and its implications for the Indo-European question.

How many other similar ‘controversial’ samples are there which we haven’t even considered? And what mechanisms are in place to control that the case of Hajji_Firuz_CA I2327 is not repeated?

Ukraine Eneolithic outlier I6561

It was not the first time that I (or many others) have alternatively questioned its subclade or its date, but the contradictory data seem to keep piling up. We can still explain all these discrepancies by assuming that the radiocarbon date is correct – seeing how it is a direct and newly reported lab analysis – because it is an isolated individual from a poorly sampled region, so he may actually be the first one to show features proper of later Corded Ware-related samples.

ukraine-eneolithic-from-caucasus
PCA of ancient Eurasian samples. An interpretation of the evolution of the Pontic-Caspian steppe populations in the Eneolithic. See full PCA.

The individual seems to be especially relevant for the Indo-European and Uralic homeland question. The last one to mention this sample in a publication was Anthony (2019), who considered it in common with two other Eneolithic samples from Dereivka to show how Anatolian farmer-related ancestry first appeared in the recently opened CHG mating network of the Pontic-Caspian steppes and forest-steppes during the Middle Eneolithic, after the expansion of Khvalynsk:

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

The main problem is that this sample has more than one inconsistent, anachronistic data compared to its reported precise radiocarbon date ca. 4045–3974 calBCE (5215±20BP, PSUAMS-2832). I summarized them on Twitter:

  • First known R1a-M417 sample, with subclade R1a-Y26 (Y2-), with formation date and TMRCA ca. 2750 BC (CI 95% ca. 3750–1950 BC), and proper of much later Steppe_MLBA bottlenecks. The closest available sample would be the Poltavka outlier of hg. R1a-Z94 (ca. 2700 BC), from a mixed cemetery that could belong to a later (likely Abashevo) layer; the closest related subclade is probably found in sample I12450 of Butkara_IA (ca. 800 BC).
  • NOTE. The formation date of upper clade R1a-Z93 is estimated ca. 3000 BC, with a CI 95% ca. 3550–2550 BC, suggesting that the actual TMRCA range for the subclade has most likely a lower maximum formation date than estimated with the available samples under Y3.

  • Ancestry and PCA cluster like Steppe_MLBA (see PCA below), different from neighbouring Sredni Stog samples of the roughly coetaneous Dereivka site (ca. 3600-3400 BC), and from a later Yamnaya sample from Dereivka (ca. 2800 BC), even more shifted toward WHG-related ancestry.
  • Allele for lactase persistence (I3910-T), found only much later among Bell Beakers, and still later in Sintashta and Steppe_MLBA samples. This suggests a strong selection in northern Europe and South Asia stemming from steppe-related (and not forest-steppe-related) peoples, postdating the age of massive Indo-European migrations.
  • Hajji Firuz Chalcolithic outlier

    My impression is that the Hajji_Firuz Chalcolithic outlier, initially dated ca. 5900-5500 BC, had much less reason to be questioned than this sample, since Pre-Yamnaya ancestry was (and apparently is still) believed by members of the Reich Lab to have come from south of the Caucasus, and to have arrived around that time or earlier to the North Caspian steppe, i.e. before the 5th millennium BC.

    The formation date of its initially reported haplogroup, R1b-Z2103, is ca. 4100 BC (CI 95% 4800-3500 BC), which seems also roughly compatible with that date and site – at least as compatible as R1a-Y3(xY2) is for ca. 4000 BC -, so it could have been interpreted as a migrant from the South Caspian region, potentially related to Proto-Anatolians, especially before the description of the Caucasus genetic barrier in Wang et al (2018). For some reason, though, the Hajji_Firuz sample was questioned, but this one didn’t even merited an interrogation mark.

    There was already a similar situation with two samples (RISE568 and RISE569) initially reported as belonging to Czech Corded Ware groups, that turned out to be Early Slavs ca. 3,000 years younger, in turn more closely related to Bell Beaker-derived cultures of Central-East Europe. It seems little has changed since that case.

    All in all, my guess is that genomic data of I6561 would have been a priori more compatible with a later period, during the expansion of East Corded Ware groups: at least Middle Dnieper culture, potentially Multi-Cordoned Ware culture, but most likely a Srubnaya-related one, given the most likely SNP mutation and TMRCA date, and the haplogroup variability found in the few samples available from that culture.

    ukraine-eneolithic-from-srubna
    PCA of ancient Eurasian samples. Marked I6561 sample within the cluster formed by Srubnaya samples. See full PCA.

    Compatibility checks

    I tried to start a thread on the possibility that the radiocarbon date was wrong, and IF it were, how likely it would be that formal stats could actually show this, or how could we automatically prevent ancestry magic fiascos.

    In other words: if this guy were a Srubnaya-related individual actually dated e.g. ca. 1700 BC, and someone would try to ‘prove’ – based on the current open source tools alone – that he was the ancestor of expanding peoples of the 4th and 3rd millennium BC (i.e. Balkan outliers, Yamnaya, Corded Ware, you name it), could these results be formally challenged?

    I was hoping for some original brainstorming where people would propose crazy, essentially impossible to understand statistical models, say plotting dozens of well-studied mutations of different geographically related ancient samples with their reported dates, to visually highlight samples that don’t exactly fit with such a feature-based time series analysis; I mean, the kind of theoretical models I wouldn’t even be able to follow after the first two tweets or so. I didn’t receive an answer like that, but still:

    I have nothing to add to these answers, because I agree that all contradictory data are circumstancial.

    The current absolute lack of this kind of validity checks for ancestry models is disappointing, though, and leaves the so-called outliers in a dangerous limbo between “potentially very interesting samples” and “potentially wrongly dated samples”. Radiocarbon date is thus – together with compatibility of population source in terms of archaeological cultures and their potential relationship – a necessary variable to take into account in any statistical design: an error in one of these variables means a catastrophic error in the whole model.

    Formal stats

    For example, in these qpAdm models, I assumed Srubnaya, Ukraine_Eneolithic_outlier, and Bulgaria_MLBA samples were roughly coetaneous and potentially related to the Srubnaya-SabatinovkaNoua cultural horizon, hence stemming from a source close to:

    1. Abashevo-like individuals (whose best proxy to date should be Poltavka_outlier I0432) potentially admixed with Poltavka-like herders; or
    2. Potapovka-like individuals potentially admixed with Catacomb-like peoples (whose best proxy until recently were probably Yamnaya_Kalmykia*).

    *To avoid adding more potential errors by merging different datasets, I have used only proxy samples available in the Reich Lab’s curated dataset of published ancient DNA.

    srubnaya-noua-sabatinovka-mlba
    Srubnaya and Noua-Sabatinovka cultural horizon during the MLBA. See full maps.

    Apart from the lack of more models for comparison (I’m not going to dedicate more time to this), the results can’t be interpreted without a proper sampling and context, either, because (1) Poltavka_o may actually be from a much later group closely related to Srubnaya; (2) Bulgaria_MLBA is only one sample; and (3) there are only two samples from Potapovka; so the models here presented are basically useless, as many similar models that have been tested looking just for a formal “best fit”.

    So feel free to chime in and contribute with ideas as to how to detect in the future whether a sample is ancestral to or derived from others. I will post here informative answers from Twitter, too, if there are any. I don’t think a discussion about the potentially wrong date in this specific sample is very useful, because this seems impossible to prove or disprove at this point. Just what tools or data would you use to at least try and assess whether samples are compatible with its reported date or not – preferably in some kind of automated sieve that takes dozens or hundreds of samples into account.

    On the bright side, there is so much more than formal stats to arrive to relevant inferences about prehistoric populations, their movements and languages. That’s why I6561 didn’t matter for the conclusion by Anthony (2019) that it was the R1b-rich Eneolithic Don-Volga-Caucasus region the most likely Indo-Anatolian and Late Proto-Indo-European homeland, due to the creation of a wide Eneolithic mating network with extended exogamy practices, where Y-chromosome bottlenecks seem to be one of the main genomic data to take into account from the Neolithic to the Middle Bronze Age.

    And that is the same reason why it doesn’t matter that much for the Proto-Indo-European or Uralic question for me, either.

    Related

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

narasimhan-spread-yamnaya-ancestry

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

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

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

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

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

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

Indo-Europeans

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

I. Afanasievo

I.1. East or West PIE?

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

I.3. Agricultural substrate

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

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

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

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

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

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

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

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

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

II. R1b-Beakers replaced R1a-CWC peoples

II.1. R1a-M417-rich Corded Ware

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

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

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

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

On Ukraine_Eneolithic I6561

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

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

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

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

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

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

II.1. R1b-L51-rich Bell Beakers

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

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

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

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

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

III. Proto-Indo-Iranian

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

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

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

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

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

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

IV. Armenian

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

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

Indus Valley Civilization and Dravidian

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

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

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

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

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

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

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

Conclusion

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

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

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

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

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

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

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

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

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

Related

Proto-Tocharians: From Afanasievo to the Tarim Basin through the Tian Shan

tocharians-early-eneolithic

A reader commented recently that there is little information about Indo-Europeans from Central and East Asia in this blog. Regardless of the scarce archaeological data compared to European prehistory, I think it is premature to write anything detailed about population movements of Indo-Iranians in Asia, especially now that we are awaiting the updates of Narasimhan et al (2018).

Furthermore, there was little hope that Tocharians would be different than neighbouring Andronovo-like populations (see a recent post on my predicted varied admixture of Common Tocharians), so the history of both unrelated Late PIE languages would have had to be explained by the admixture of Afanasievo-related groups with peoples of Andronovo descent and their acculturation.

However, data reported recently by Ning, Wang et al. Current Biology (2019) confirmed that peoples of mainly Afanasievo ancestry – as opposed to those of Corded Ware-related ancestry expanding with the Srubna-Andronovo horizon – spread the Tocharian branch of Proto-Indo-European from the Altai into the Tian Shan area, surviving essentially unadmixed into the Early Iron Age.

This genetic continuity of Tocharians will no doubt help us disentangle a great part the ethnolinguistic history of speakers of the Tocharian branch of Proto-Indo-European, from Pre-Proto-Tocharians of Afanasievo to Common Tocharians of the Late Bronze Age/Iron Age eastern Tian Shan.

NOTE. Tocharian’s isolation from the rest of Late PIE dialects and its early and intense language contacts have always been the key to support an early migration and physical separation of the group, hence the traditional association with Afanasievo, a late Repin/early Yamna offshoot. Even with the current incomplete archaeological and genetic picture, there is no other option left for the expansion of Tocharian.

It is not possible to use the currently available ancestry data to map the evolution of Afanasievo ancestry, lacking a proper geographical and temporal transect of Central and East Asian groups. In spite of this, Ning, Wang, et al. (2019) is a huge leap forward, discarding some archaeological models, and leaving only a few potential routes by which Tocharians may have spread southward from the Altai.

NOTE. I have updated the maps of prehistoric cultures accordingly, with colours – as always – reflecting the language/ancestry evolution of the different groups, even though the archaeological data of some groups of Xinjiang remains scarce, so their ethnolinguistic attribution – and the colours picked for them – remain tentative.

xinjiang-andronovo-xiaohe-horizon-bronze-iron-age
A rough timeline of related archaeological sites from North Eurasia. Image modified from Yang (2019).

Tocharians

The recent book Ancient China and its Eurasian Neighbors. Artifacts, Identity and Death in the Frontier, 3000–700 BCE, by Linduff, Sun, Cao, and Liu, Cambridge University Press (2017) offers an interesting summary of the introduction of metalworking into western China.

Here are some relevant excerpts (emphasis mine):

Although [the Xinjiang] route is not uniformly agreed upon (Shelach-Lavi 2009: 134–46), this western transmission has been thought to have passed through eastern Kazakhstan, especially as it is manifest in Semireiche, with Yamnaya, Afanasievo (copper) and Andronovo (tin bronze) peoples (Mei 2000: Fig. 3). From Xinjiang this knowledge has been thought to have traveled through the Gansu Corridor via the Qijia peoples (Bagley 1999) and then into territories controlled by dynastic China. The dating of this process is still a problem, as the sites and their contents in Xinjiang are consistently later than those in Gansu, suggesting that the point of contact was in Gansu and that the knowledge then spread from there westward.

1. Eneolithic Altai

tocharians-chalcolithic-eneolithic
Afanasievo expansion ca. 3300-2600 BC. See full culture and ancient DNA maps.

The Afanasievo sites, as they are identified in Mongolia, for instance, make up an Eneolithic culture analogous to that of southern Siberia (3100/2500–2000 BCE) in the Upper Yenissei Valley that is characterized by copper tools and an economy reliant on horse, sheep and cattle breeding as well as hunting. (…) The Afanasievo is best known through study of its burials, which typically include groups of round barrows (kurgans), each up to 12 m in diameter with a stone kerb and covering a central pit grave containing multiple inhumations. In their Siberian context, burial pottery types and styles have suggested contacts with the slightly earlier Kelteminar culture of the Aral and Caspian Sea area.

The Afanasievo culture monuments, located in the northern Altai and in the Minusinsk Basin (the western Sayan), have been seen as analogous evidence for cross-Eurasian exchange. These complexes contain small collections of metal, and many of the items are made of brass, although golden, silver and iron ornaments were also identified. A mere one-fourth of these objects are tools and ornaments, while the rest consist of unshaped remains and semi-manufactured objects. Its metallurgical tradition has recently been dated by Chernykh to as early as 3100 to 2700 BCE (1992),making it more compatible chronologically with the early brass-using sites in Shaanxi mentioned above. Kovalev and Erdenebaatar have excavated barrows in Bayan-Ulgii, Mongolia, that have been carbon-dated to the first half of the third millennium BCE and associated by ceramic types and styles and burial patterns with the Afanasievo (Kovalev and Erdenebaatar 2009: 357–58). These mounded kurgans were covered with stone and housed rectangular, wooden-faced tombs that included Afanasievo-type bronze awls, plates and small “leaf-shaped” knife blades (Kovalev and Erdenebaatar 2009: Figs. 6 and 7).

They also excavated sites belonging to the more recently identified Chemurchek archaeological culture, located in the foothills of the Mongolian Altai (Kovalev 2014, 2015) (Fig. 2.6). These sites are carbon-dated to the same period as the Afanasievo burials or to c. 3100/2500–1800 BCE (six barrows in Khovd aimag and four in Bayan-Ulgo aimag). In the rectangular stone kerbed Chemurchek slab burials (Ulaaanhus sum, Bayan-ul’gi aimag and so forth), bronze items included awls; and at Khovd aimag, Bulgan sum, in addition to stone sculptures, three lead and one bronze ring were excavated (Kovalev and Erdenebaatar 2009: Figs. 2 and 3; Fig. 2.6). Although we will not know if they were produced locally until much further investigation is undertaken, these discoveries do document knowledge of various uses and types of metal objects in western and south central Mongolia. The types of metal items thus far recovered are simple tools (awls) and rings (ornamental?) not unlike those associated with Andronovo archaeological cultures as well.

This is a complex circumstance where archaeological evidence is not complete, but raises very important questions about transmission of metallurgical knowledge to and from areas in present-day China. In the 1970s some Afanasievo mounds were excavated in Central Mongolia by a Soviet–Mongolian expedition led by V. V. Volkov and E. A. Novgorodova (Novgorodova 1989: 81–85). Unfortunately, these mounds did not yield metal objects, only ceramics, but they show that the Afanasievo culture with the Eneolithic metallurgical tradition of manufacturing pure copper items had already moved east at least far as central Mongolia. In 2004, Kovalev and Erdenebaatar investigated a large Afanasievo mound, Kulala ula, in the extreme northwest of Mongolia, near the Russian border (Kovalev and Erdenebaatar 2009). There they found a copper knife and awl (Fig. 2.5). There are five C14 dates on wood, coal and human bones from this mound, which belong to the period 2890–2570 BCE. This shows that the Afanasievo culture were carriers of technology and produced artifacts in the first half of the third millennium BCE and that they also moved south along the foothills of the Mongolian Altai. Afanasievo culture in Altai and the Minusinsk basin is dated by C14 to 3600–2500 BCE (Svyatko et al. 2009; Polyakov 2010). In the north of Xinjiang in the Altai district, several typical egg-shaped vessels and two censers of Afanasievo types were found. Some of these have been obtained from the stone boxes (chambers of megalithic graves of the Chemurchek culture) (Kovalev 2011). Thus, the Afanasievo tradition of pure copper metallurgy must have spread to the northern foothills of the Tienshan Mountains no later than the mid-third millennium BCE. The links with Afanasievo and local cultures adjacent to and south of the mountains into present-day China can now be assumed.

tocharians-chalcolithic-late
Afanasievo – Chemurchek evolution ca. 2600-2200 BC. See full culture and ancient DNA maps.

2. Bronze Age Altai

Kovalev and Erdenebaatar (2014a) and later Tishkin, Grushin, Kovalev and Munkhbayar (2015) in Western Mongolia conducted large-scale excavations of megalithic barrows of the Chemurchek culture (dated about 2600–1800 BCE). This peculiar culture appeared in Dzungaria and the Mongolian Altai in the second quarter of the third millennium BCE and for some time existed together with the late Afanasievo culture, as evidenced by the findings of Afanasievo ceramics in Chemurchek graves, in the stone boxes. Unfortunately, in China we do not yet know of any metal object related,without doubt, to the Chemurchek culture. Kovalev, Erdenebaatar, Tishkin and Grushin found several leaden ear rings and one ring of tin bronze in three excavated Chemurchek stone boxes (Kovalev and Erdenebaatar 2014a; Tishkin et al. 2015). Such lead rings are typical for Elunino culture,which occupied the entire West Altai after 2400–2300 BCE (Tishkin et al. 2015). This culture had developed a tradition of bronze metallurgy with various dopants, primarily tin. Thus, the tradition of bronze metallurgy as early as this time could have penetrated the Mongolian Altai far to the south. In addition, in the Hadat ovoo Chemurchek stone box, Kovalev and Erdenebaatar discovered stone vessels refurbished with the help of copper “patches,” indicating the presence there of metallurgical production (Fig. 2.7) (Kovalev and Erdenebaatar 2014a). In one of the secondary

Chemurchek graves unearthed by Kovalev and Erdenebaatar in Bayan-Ulgi (2400–2220 BCE), a bronze awl was found (Kovalev and Erdenebaatar 2009). Kovalev and Erdenebaatar also discovered a new culture in the territory of Mongolia (Map 2.3), one that begins immediately after Chemurchek – Munkh-Khairkhan culture (Kovalev and Erdenebaatar 2009, 2014b). To date, about 17 mounds of this culture have been excavated in Khovd, Zavkhan, Khovsgol, Bulgan aimag of Mongolia. This culture dates from about 1800 to 1500 BCE, that is, contemporary with the Andronovo culture. Therefore, the Andronovo culture does not extend far into the territory of Mongolia. Three knives without dedicated handles or stems and five awls have been found in the Munkh-Khairkhan culture mounds (Fig. 2.8). All these products are made of tin bronze. (…) Additionally, eight Late Bronze Age burials (c. 1400–1100 BCE) were unearthed in the Bulgan sum of Khovd aimag and belong to another previously unknown culture called Baitag. And in the Gobi Altai, a new group of “Tevsh” sites dating to the Late Bronze Age were defined in Bayankhongor and South Gobi aimags (Miyamoto and Obata 2016: 42–50). From these Tevsh and Baitag sites, we see the expansion of burial goods to include beads of semiprecious stones (carnelian), bronze beads, buttons and rings and even the famous elaborate golden hair ornaments (Tevsh uul;Bogd sum;Uverkhanagia aimag) from the Baitag barrows (Kovalev and Erdenebaatar 2009: Fig. 5; Miyamoto and Obata 2016).

2.1. Chemurchek

About the Chemurchek culture, from A re-analysis of the Qiemu’erqieke (Shamirshak) cemeteries, Xinjiang, China, by Jia and Betts JIES (2010) 38(4):

The major characteristics of Qiemu’erqieke Phase I include:

  1. Burials with two orientations of approximately 20° or 345°.
  2. Rectangular enclosures built using large stone slabs. The size of the enclosure varies from a maximum of 28 x 30 m.*to a minimum of 10.5 x 4.4 m. (Figure 8, Table 2).
  3. *The stone enclosure located near Hayinar is the largest one at approximately 30 x 40 m. based on pacing of the site during a visit by the authors in 2008.

  4. Almost life-sized anthropomorphic stone stelae erected along one side of the stone enclosures (Lin Yun 2008).
  5. Single enclosures tend to contain one or more than one burial, all or some with stone cist coffins.
  6. The cist coffin is usually constructed using five large stone slabs, four for the sides and one on top, leaving bare earth at the base (Zhang Yuzhong 2007). Sometimes the insides of the slabs have simple painted designs (Zhang Yuzhong 2005).
  7. Primary and secondary burials occur in the same grave.
  8. Some decapitated bodies (up to 20) may be associated with the main burial in one cist.
  9. Bodies are commonly placed on the back or side with the legs drawn up.
  10. Grave goods include stone and bronze arrowheads, handmade gray or brown round-bottomed ovoid jars, and small numbers of flat-bottomed jars (Fig. 7).
  11. Clay lamps appear to occur together with roundbottomed jars.
  12. Complex incised decoration on ceramics is common but some vessels are undecorated.
  13. The stone vessels are distinctive for the high quality of manufacture.
  14. Stone moulds indicate relatively sophisticated metallurgical expertise.
  15. Artefacts made from pure copper occur.
  16. Sheep knucklebones (astragali) imply a tradition (as in historical and modern times) of keeping knucklebones for ritual or other purposes. They also indicate the herding of domestic sheep as part of the subsistence economy.
tocharians-bronze-age-early
Chemurchek culture ca. 2200-1750 BC. See full culture and ancient DNA maps.

Chemurchek dating

Available evidence suggests that the date range for Qiemu’erqieke Phase I should fall from the later third into the early second millennium BC. There are several reasons to suggest that the time span is around the early second millennium BC. Lin Yun (2008) (…) maintains that the bronze artefacts found in Phase I show a greater sophistication in the level of copper alloy technology than that of the pure copper artefacts common to the Afanasievo tradition. On this basis it might be suggested that the Afanasievo could be considered to be Chalcolithic with a time span across much of the third millennium BC ( Gorsdorf et al. 2004: 86, Fig. 1). Qiemu’erqieke Phase I, however, should more properly be considered as Bronze Age.

Lin Yun also used the bronze arrowhead from burial Ml 7 to narrow down the date of Qiemu’erqieke Phase I. Two arrowheads were found in this burial, one of them leaf shaped with a single barb on the back (Fig. 7:4). A similar arrowhead, together with its casting mould, has been found at the Huoshaogou site of Siba tradition (Li Shuicheng 2005, Sun Shuyun and Han Rufen 1997), in Gansu province, northwest China, dated around 2000-1800 BC (Li Shuicheng and Shui Tao 2000) . This supports a date in the early second millennium BC for the Qiemu’erqieke arrowhead. The painted, round-bottomed jar from the Tianshanbeilu cemetery Qia Weiming, Betts and Wu Xinhua 2008: Fig. 7, bottom left) has been considered as a hybrid between the Upper Yellow River Bronze Age cultures of Siba in northwest China and the steppe tradition of Qiemu’erqieke in west Siberia (Li Shuicheng 1999). If this assumption is correct, the date of Tianshanbeilu, around 2000 BC, can be used as a reference for Qiemu’erqieke Phase I (Jia Weiming, Betts and Wu Xinhua 2008, Lin Yun 2008, Li Shuicheng 1999). Stone arrowheads found in Qiemu’erqieke Phase I also imply that the date is likely to fall within the earlier part of the Bronze Age as no such stone arrowheads have yet been found elsewhere in sites of the Bronze Age in Xinlang dated after the beginning of the second millennium BC.*
*For example Chawuhu and Xiaohe cemeteries (Xinjiang Institute of Archaeology 1999, 2003).

pottery-afanasevo-chemurchek
Pottery of Afanasevo and East European traits from the Chemurchek complex. Image modified from Kovalev (2017).

(…) Pottery “oil burners” (goblet-like ceramic vessels, possibly lamps) have been found in three traditions: Afanasievo (Gryaznov and Krizhevskaya 1986:21), Okunevo and Qiemu’erqieke. It is believed that this oil-burner found in Siberia and the Altai is a heritage from the Yamnaya and Catacomb
cultures (Sulimirski 1970: 225, 425; Shishlina 2008:46) in the Caspian steppe further to the west, but does not seem to exist in known Andronovo cultures.
The oil-burner tends to disappear after around 2300 BC during the mid-Okunevo period. It is, however, possible that the tradition continues longer in the Qiemu’erqieke sites.

The construction of the stone enclosures also reveals a close connection between Qiemu’erqieke Phase I and the mid and late Okunevo tradition (Sokolova 2007). Slab built stone enclosures emerged in both the Okunevo and Afanasievo traditions (Gryaznov and Krizhevskaya 1986:15-23, Kovalev 2008, Sokolova 2007, Anthony 2007:310, Koryakova and Epimakhov 2007). In the early Afanasievo the enclosure is circular with no cist coffin (Anthony 2007:310, Gryaznov and Krizhevskaya 1986:20), but in the early stage of the Okunevo square stone enclosures with a single cist burial are dominant. Square or rectangular stone enclosures are a marked feature of Qiemu’erqieke Phase I, suggesting temporal relationships between Qiemu’erqieke Phase I and the Okunevo. In Okunevo chronological group II, possibly with influence from the Anfanasievo, circular stone enclosures appeared in combination with rectangular enclosures within individual cemeteries, referred to by Sokolova (2007: table 2) as hybrid examples. By Okunevo chronological group III, rectangular stone slab enclosures with multi-burials emerged again. This is the dominant form in Qiemu’erqieke Phase I. Okunevo burial traditions changed again to single cist burials in the late stage around chronological group V ( Sokol ova 2007). A specific mortuary rite of decapitated burials exists in both the Qiemu’erqieke and Okunevo traditions (Sokolova 2007, Chen Kwang-tzuu and Hiebert 1995), as does the occasional occurrence of painted designs on the interior of the slabs forming the cists ( e.g., Khavrin 1997: 70, fig. 4; 77: tab. IV.5). Based on these comparisons, the date of Qiemu’erqieke Phase I may well parallel that of the Okunevo from at least chronological group II around 2400 BC (Gorsdorf et al. 2004: fig. 1).

khuh-udzuur-barrow
Khuh Udzuuriin I-1 elite barrow (ca. 2470-2190 BC). Modified from Image modified from Kovalev (2014).

In addition to the pottery making tradition, the anthropomorphic stone stelae may also have earlier antecedents. In the Okunevo assemblage there are anthropomorphic stelae that are longer, thinner and more abstract than those of Qiemu’erqieke. There is no indication of such stelae in the Afanasievo tradition (Gryaznov and Krizhevskaya 1986:15-23). However, further to the west, anthropomorphic stone stelae are associated with the Kemi-Oba and Yamnya cultures around the third millennium BC (Telegin and Mallory 1994; Figure 13). Some major characteristics of these stelae such as the icons on the front face of the stelae (Telegin and Mallory 1994:8-9) also appear on stelae found in Qiemu’erqieke Phase I. Recalling the oil burners that may have been inherited from the Yamnya culture and which are found in the Afansievo, Okunevo and Qiemu’erqieke Phase I, it migh t be possible to speculate that Qiemu’erqieke Phase I has its origins even earlier than the first half of the third millennium BC. This idea has also been suggested by Kovalev ( 1999).

Despite the affinities with the Okunevo cultural tradition, Qiemu’erqieke Phase I appears to be a discrete regional variant. The ceramic assemblage shows traits unique to this cluster of sites, while the anthropomorphic stelae are also distinctive markers of this tradition.

khuh-udzuur-stela
Khuh Udzuur anthropomorphic stone stela, oriented toward the south – south-east. Image modified from Kovalev (2014).

3. Bronze Age Xinjiang

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

It also offered a full summary of findings from prehistoric sites of Xinjiang related to the arrival of a cultural package from the Altai region, ultimately connected to Afanasievo. Relevant excerpts include the following (emphasis mine):

In Bronze Age Xinjiang, burials were diverse but also show some common features between different geographic sections. The main three mountains, including Kunlun Mountains, Tian Shan (mountains) and Altai Mountains, enclose the Tarim Basin, and the Dzungaria Basin, but leave the eastern part of the Tarim Basin and the south-eastern part of the Dzungaria Basin open (with easy access to the surroundings). The Hami Basin is located at the transitional area, connecting the two basins. Burials are mainly spread along the edge of the mountain ranges.

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

3.1. The Lop Nur region

In the Lop Nur region, the Xiaohe cemetery (2000-1450 BCE) and the Gumugou cemetery (1900-1800 BCE) had many common features shared, and so is the Keliyahe northern cemetery:

  • Cemeteries were located in sandy areas;
  • Rectangular/boat-shaped wooden coffins with monuments of wooden planks or poles;
  • Coffins had no bottoms;
  • The dead were placed lying straight on the back;
  • The dead were commonly buried in single graves.

The Gumugou cemetery contained six special sun-radiating-spokes burial pattern in addition to the normal burials, which were similar to the wooden coffin graves of the Xiaohe cemetery.

NOTE. For more on Xiaohe and Gumugou, see the recent post on Proto-Tocharians. See other papers on the Andronovo horizon for other Early to Middle Bronze Age cultural groups less clearly associated with the Xiaohe horizon, like Hazandu, Xintala, or the Chust culture.

From Shuicheng (2006):

An assemblage of early bronzes had been recovered from northwestern Xinjiang and the periphery of Dzungaria 准噶尔 Basin. It comprises a variety of utilitarian tools and weapons, and a small number of apparels. These artifacts bear the stamps of Andronovo Culture in form, artifact type and decorative pattern. The metallographic analysis on selected artifacts indicates that they comprise mainly of tin-bronzes that contain 2–10% of tin. Moreover, the chemical compositions of these artifacts are similar to that of the Andronovo Culture. Latter date (first half of the 1st millennium BC) artifacts of the assemblage include a small number of arsenic bronzes. In all, during the period between the mid-2nd and mid-1st millennium BC, copper and bronze artifacts coexisted in this region, albeit tin-bronze comprised the majority. The composition of alloy did not show significant change over time. Some colleagues pointed out that the Nulasai 奴拉赛 site at Nileke 尼勒克 County in the Yili 伊犁 River basin of Xinjiang was the pioneer in the use of “sulphuric ore–ice copper–copper”technology. It is also the only early smelting site in Euro-Asia that arsenic ore was added to deliberately produce an alloy

tocharians-bronze-age-middle
Prehistoric cultures of Xinjiang during the Middle Bronze Age. See full culture and ancient DNA maps.

3.2. The Hami Basin-the Balikun Grassland

From Yang (2019):

The Hami Basin-the Balikun Grassland area is located at the eastern part of Tian Shan. The area is divided in a northern basin and a southern basin by the east-west stretch of the Tian Shan. In the Hami Basin-the Balikun Grassland area, the main type of burials were earth-pit graves in the early Bronze Age, and burials of stone-pit with barrows became more common in the late Bronze Age. The Hami-Tianshan-Beilu cemetery is a representative of the earth-pit graves. The features of the Hami-Tianshan-Beilu cemetery (2000-1500 bce) here were:

  • Rectangular earth pit graves;
  • The dead were often in a hocker position lying on one side;
  • Commonly a single dead in one grave.
balikun-grassland
The Balikun grassland today (source).

The Hami-Wubu cemetery (earlier than 1000 bce) and the Yanbulake cemetery (1200-600 bce) are representatives of another common earth-pit graves. Common features here were:

  • Rectangular earth pits, with two storeys and/or roofed with wooden boards;
  • The dead was placed in a hocker position lying on one side;
  • Mostly a single dead in one grave.

Later there appeared more stone-pit graves in this area, and the features can be summarized as:

  • Round burial mounds, commonly constructed by stones or a mix of stones and earth;
  • Burial mounds with a sunken top or a normal (dome) top;
  • The diameter of the burial mounds varied between 3 and 25.4 m (but not necessarily limited in this scope);
  • Circular or rectangular stone kerbs;
  • Rectangular stone pits, constructed by earth, or stones, or a mix of earth and stones;
  • Rectangular stone pits contained wooden coffins (represented by the Yiwu Baiqi’er cemetery).
hami-basin-balikun-grassland-iron-age-burials
Some representatives of stone burials in the Hami Basin – the Balikun Grassland in the Iron Age (Adapted from: Xinjiang 2011, 29-41). Image modified from Yang (2019).

In the Hami Basin, the Bronze Age cemeteries show common burial features like earth pits and hocker position of the dead. With similar pottery styles in the Hami-Tianshan-Beilu cemetery to those in the Machang and Siba cultures (Xinjiang 2011: 17), it suggests possible cultural influence or people’s migrating from the Hexi Corridor in the east.

In the Balikun Grassland, burials in an earlier time contained mostly earth-pit graves but also a small number of stone-pit graves. The pebbles were imbedded in the floors and the walls of the graves in a rectangular shape, e.g. the Balikun-Nanwan cemetery (1600-1000 bce). In a later time, there appeared huge burial mounds with a sunken top, and with the diameters of the burial mounds varying from 3 to 25.4 m, e.g. the Balikun-Dongheigou cemetery and the Balikun-Heigouliang cemetery. The Yiwu-Bai’erqi and the Yiwu-Kuola cemeteries contained either round stone burial mounds or circular stone kerbs on the ground surface. Considering the three burial elements including burial mounds, stone pits and circular kerbs, the later period cemeteries in the Balikun Grassland were actually similar to cemeteries from the southern edge of the Altai Mountain area.

From Shuicheng (2006):

The Nanwan 南湾 cemetery site at Kuisu 奎苏 Town, Balikun 巴里坤 (1600–1100 BC) also yielded an assemblage of early bronzes. The style of its early phase artifacts is similar to that of the burials distributed in the North Tianshan Route. Some sorts of cultural connection should have existed between the two.

The dates of Yanbulake 焉不拉克 Culture (1300–700 BC) are comparatively late. Its metallurgy was a continuation of the western China tradition. Artifact types include a variety of utilitarian tools, weapons and apparels.

tocharians-bronze-age-late
Prehistoric cultures of Xinjiang during the Late Bronze Age. See full culture and ancient DNA maps.

3.3. The Turpan Basin-the middle part of Tian Shan

From Yang (2019):

Turpan Basin is located at the western part of the Hami Basin, and lies at the southern edge of the eastern Tian Shan. In the Turpan Basin-the middle part of Tian Shan area, the main representative of the Bronze Age cemeteries is the Yanghai Nr.1 cemetery. The features here were:

  • Elliptic earth pit graves, commonly covered by round logs on the top;
  • Some graves contained burial beds made of round logs or reeds;
  • The dead were mainly placed lying straight on the back;
  • Mostly a single dead in one grave.

In Iron Age, the stone burials became dominant, but the stone burials varied in different regions of the Turpan Basin-the middle part of Tian Shan area. Graves containing burial mounds, stone pit, and circular stone kerbs are represented by the Shanshan-Ertanggou cemetery, the Tuokexun-Alagou cemetery, the Urumqi-Chaiwobu cemetery and the Urumqi-Yizihu-Sayi cemetery, etc. The stone funeral construction features here are similar to those contemporary cemeteries in the Hami Basin-the Balikun Grassland area.

3.4. The southern edge of the western and middle part of Tian Shan

In the southern edge of the western and middle part of Tian Shan area, the main representatives of the late Bronze Age cemeteries are the Hejing-Chawuhu Nr.4 cemetery (around 1000-500 bce), the Hejing-Xiaoshankou cemetery, the Baicheng-cemetery, etc. The main burial features of the late Bronze Age and the early Iron Age cemeteries (see Fig.12) here were:

  • Burial mounds, constructed by stones or a mix of stones and earth;
  • Irregular circular or rectangular stone kerbs;
  • Stone pit graves in a bell-shape or a rectangular shape;
  • Stone pit graves constructed by imbedding pebbles or stone slabs in walls and floors;
  • The dead were often placed lying on their back with bent legs;
  • The dead were commonly reburied a second time with multiple burials.

From the late Bronze Age to the early Iron Age in this area, the burial traditions tended to be in a more varied way. In the stone burials with stone kerbs, there is a mixture of stone pit and earth pit graves. The burial features of the Iron Age cemeteries in this section were similar to those contemporary both in the Hami Basin-the Balikun Grassland area and in the Turpan Basin-the middle part of Tian Shan area.

From Shuicheng (2006):

The Chawuhu 察吾呼 Culture (1100–500 BC) distributes on the foothills between the middle section of the Tianshan Mountain Ranges and Tarim River. Its bronze assemblage comprises a variety of weapons, utilitarian tools and small apparels. They show no apparent temporal change in form and type through the four cultural phases. In addition, bronzes bear the Chawuhu characteristics were found in Hejing 和静, Baicheng 拜城 and Luntai 轮台 (Bügür). Yet, sites distributed along the Tarim River, such as Heshuo 和硕, Kuga 库车and Aksu 阿克苏, yielded remains of a bronze culture different from that of Chawuhu. Bronzes recovered include double-eared socketed axe, arrowheads, awls, knives, needles and bracelets. Their absolute dates have been estimated to be earlier than that of Chawuhu.

tocharians-iron-age-early
Prehistoric cultures of Xinjiang during the Early Iron Age. See full culture and ancient DNA maps

3.5. The Pamir Plateau

From Yang (2019):

A typical Bronze Age cemetery from the Pamir Plateau area is the Tashenku’ergan-Xiabandi cemetery (around 1000-500 bce). The burial features here were:

  • Mainly inhumations, but also a few cremations;
  • Burial mounds, constructed of stones;
  • Irregular circular or rectangular stone kerbs;
  • Mostly a single dead in one grave;
  • The dead was placed in a hocker position lying on one side.

The adoption of burial customs from the east supports the migration of Afanasievo-related peoples from the Tian Shan up to the Pamir Plateau, strongly influencing the findings of the Xiabandi cemetery, which has been dated from an early Bronze Age phase (ca. 1500-300 BC) to a late date up to ca. 600 BC.

While it is today unclear how far the Afanasievo admixture reached into the western Xinjiang, it seems that the Pamir Plateau remained culturally connected to neighbouring Andronovo-related cultures in pottery and metallurgical innovations, hence their language probably belonged – during most part of the Bronze and Iron Ages – to the Indo-Iranian branch, even though specific dialects might have changed with each new attested group.

In particular, it is possible that the early Andronovo groups related to the Xiaohe Horizon spoke Indo-Aryan or West Iranian dialects, while Saka-related groups replaced them – or an intermediate Tocharian-speaking group – with East Iranian dialects. A close interaction with West Iranian would justify the known ancient borrowings of Tocharian, although they could also be explained by contacts with Chust-related groups farther west. For more on this, see Ged Carling’s work on the different layers of Iranian loans.

Xinjiang BA/IA Summary

From Yang (2019):

In the early Bronze Age, there are distinct regional differences in the burial customs in and surrounding the Tarim Basin. At the southern edge of the Altai Mountains area, the burial customs included stone burial mounds, stone pit graves, circular or rectangular stone kerbs and stone human sculptures; the dead were placed lying straight on the back. In the Hami Basin-the Balikun Grassland area, the burial customs included earth pit graves; the dead were placed in a hocker position lying on one side. In the Turpan Basin-the middle part of Tian Shan area, the burial customs included earth pit graves; the dead were placed lying straight on the back. In the Lop Nur region, the burial customs included wooden coffins buried in sand; the dead were placed lying straight on the back.

But from the late Bronze Age to the early Iron Age, there was a common shift in burial customs from earth pit graves to stone burials in the Hami Basin-the Balikun Grassland area and in the Turpan Basin-the middle part of Tian Shan area. The main features of the stone burials include stone burial mounds, circular or rectangular stone kerbs, and the stone pit graves in the cemeteries. Similar stone burial customs commonly appeared at the southern edge of the western and middle part of Tian Shan area and the Pamir Plateau area in Iron Age. The burial features in most areas are in a mixture of both the earth pit graves and stone pit graves, especially in the Hami Basin-the Balikun Grassland area and the Turpan Basin-the middle part of Tian Shan area.

xinjiang-bronze-age-iron-age

From Shuicheng (2006):

Historians of metallurgy conducted metallographic analyses on a sample of 234 metal specimens recovered from 16 localities in eastern Xinjiang. They concluded that the metallurgic industry in eastern Xinjiang could be roughly partitioned into three developmental phases. The early phase is represented by the burials distributed in the North Tianshan Route. The majority of the metal assemblage was tin-bronzes; however, copper and arsenic-bronzes maintained considerable proportions. The middle phase is represented by the burials at Yanbulake. During this phase, tin-bronze still maintained the majority; the proportion of arsenic-bronze increased, and some of them were high arsenic-bronzes. The late phase is represented by the burials at Heigouliang 黑沟梁. The composition of lead increased in the bronze alloy in the expense of arsenic. In addition, this phase witnessed the appearance of high tin-bronze that composed up to 16% of tin and the appearance of brass, that is, an alloy of copper and zinc. The bronze alloy consistently contained significant amount of impurities regardless of temporal difference. Casting and forging technologies coexisted throughout the three phases. The early bronzes (2000–500 BC) of eastern Xinjiang, in general, contained arsenic; however, the composition of arsenic was usually under 8%, but a few artifacts contained more than 20% arsenic. In all, arsenic had long been used in the alloy-forming of the early bronzes in eastern Xinjiang. Consequently, arsenic-bronzes were widely found in the prehistoric archaeology of the region. The artifact types, chemical compositions and manufacture techniques of the bronze assemblage of the burials of the North Tianshan Route are similar to those of Siba Culture, indicating that eastern Xinjiang had played a significant role in the East-West interactions.

An assemblage of early bronzes had been recovered from northwestern Xinjiang and the periphery of Dzungaria 准噶尔 Basin. It comprises a variety of utilitarian tools and weapons, and a small number of apparels. These artifacts bear the stamps of Andronovo Culture in form, artifact type and decorative pattern. The metallographic analysis on selected artifacts indicates that they comprise mainly of tin-bronzes that contain 2–10% of tin. Moreover, the chemical compositions of these artifacts are similar to that of the Andronovo Culture. Latter date (first half of the 1st millennium BC) artifacts of the assemblage include a small number of arsenic-bronzes. In all, during the period between the mid-2nd and mid-1st millennium BC, copper and bronze artifacts coexisted in this region, albeit tin-bronze comprised the majority.

tocharians-iron-age-late
Prehistoric cultures of Xinjiang during the Late Iron Age. See full culture and ancient DNA maps.

Tocharians in population genomics

Prehistoric population movements between the Altai and the Tian Shan are difficult to pinpoint, not the least because of the division of these territories among three different countries and their archaeological teams, only recently (more) open to the international scholarship.

The available schematic archaeological picture, where migrations could only be roughly inferred, has been recently updated to a great extent by Ning, Wang et al. (2019), whose genetic analysis of the samples is as thorough as anyone could have asked for, with a level of detail which matches the complex genetic picture of the region by the Iron Age.

As a summary, here is what they described about the samples from Shirenzigou (ca 400-200 BC), corresponding to the Iron Age populations of the Hami Basin-the Balikun Grassland area, and closely related to the preceding Yanbulake Culture:

As shown in Figure S3, the Steppe_MLBA populations including Srubnaya, Andronovo, and Sintashta were shifted toward farming populations compared with Yamnaya groups and the Shirenzigou samples. This observation is consistent with ADMIXTURE analysis that Steppe_MLBA populations have an Anatolian and European farmer-related component that Yamnaya groups and the Shirenzigou individuals do not seem to have. The analysis consistently suggested Yamnaya-related Steppe populations were the better source in modeling the West Eurasian ancestry in Shirenzigou.

biplot-yamnaya-tocharians-shirenzigou
Biplot of f3-outgroup tests illustrating the Kostenki14 and Anatolia_N like ancestries in Shirenzigou individuals. Most Shirenzigou individuals were on a cline with Yamnaya and European hunter-gatherer groups, lacking the European farmer ancestry as compared to the Steppe_MLBA populations such as Andronovo, Srubnaya and Sintashta [S1-S5]. Horizontal and vertical bars represent ± 3 standard errors, corresponding to form of outgroup f3 tests on the x axis and y axis respectively.

We continued to use qpAdm to estimate the admixture proportions in the Shirenzigou samples by using different pairs of source populations, such as Yamnaya_Samara, Afanasievo, Srubnaya, Andronovo, BMAC culture (Bustan_BA and Sappali_ Tepe_BA) and Tianshan_Hun as the West Eurasian source and Han, Ulchi, Hezhen, Shamanka_EN as the East Eurasian source. In all cases, Yamnaya, Afanasievo, or Tianshan_Hun always provide the best model fit for the Shirenzigou individuals, while Srubnaya, Andronovo, Bustan_BA and Sappali_Tepe_BA only work in some cases.

p-values-shirenzigou-samples-han-chinese
Table S2. P values in modelling a two-way (P=rank 1) admixture in Shirenzigou samples using each of the four populations (Bustan_BA, Sappali_Tepe_BA, Andronovo.SG, Srubnaya) together with Han Chinese as two sources [S6], Related to Figure 2. We used the following set of outgroups populations: Dinka, Ust_Ishim, Kostenki14, Onge, Papuan, Australian, Iran_N, EHG, LBK_EN.

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

In the PCA, ADMIXTURE, outgroup f3 statistics [see Figure S4], as well as f4 statistics (Table S3), we observed the Shirenzigou individuals were closer to the present day Tungusic and Mongolic-speaking populations in northern Asia than to the populations in central and southern China, suggesting the northern populations might contribute more to the Shirenzigou individuals. Based on this, we then modeled Shirenzigou as a three-way admixture of Yamnaya_Samara, Ulchi (or Hezhen) and Han to infer the source from the East Eurasia side that contributed to Shirenzigou. We found the Ulchi or Hezhen and Han-related ancestry had a complicated and unevenly distribution in the Shirenzigou samples. The most Shirenzigou individuals derived the majority of their East Eurasian ancestry from Ulchi or Hezhen-related populations, while the following two individuals M820 and M15-2 have more Han related than Ulchi/ Hezhen-related ancestry

It is unclear whether the Chemurchek population will show a sizeable local contribution from neighbouring groups. The fact that Okunevo shows 20% Yamnaya-related ancestry strongly supports the nature of neighbouring stone-grave-building peoples of the Altai and the northern Tian Shan as mostly Afanasievo-like, and the apparent lack of contributions of Srubna/Andronovo-like ancestry in the early Hami-Balikun stone burial builders also speaks for radical population replacement events reaching the areas south of Tian Shan, at least initially.

While ancestry cannot settle linguistic questions, it seems that nomads of the Gansu and Qinghai grasslands retained an ancestry close to Andronovo, whereas nomads of the Hami Basin-Balikun grasslands and related populations of Xinjiang remained closely related to Afanasievo. This doesn’t preclude that the ancestors of the Yuezhi became acculturated under the influence of peoples from eastern Xinjiang, but all data combined suggest an isolation of both populations – relative to other groups and to each other – and it is therefore more likely that they spoke Indo-Iranian-related languages rather than a language of the Tocharian branch.

Haplogroups

In an interesting twist of events, despite the initially reported hg. R1b and Q, Tocharians from Shirenzigou actually show a haplogroup diversity comparable to that attested in other late Iron Age populations: a similar diversity is seen, for example, among Germanic, Baltic, and Balto-Finnic peoples of the Baltic region; among East Germanic or Scythians of the north Pontic region; or among Mediterranean peoples sampled to date. Iron Age peoples show thus a complex sociopolitical setting that overcame the previous patrilineal homogeneity of Bronze Age expansions.

tocharians-pca
PCA and ADMIXTURE for Shirenzigou Samples. Modified from the original to include in black squares samples related to Yamnaya. Modified from the paper to include labels of modern populations and a dotted lines with the cline formed by Shirenzigou, from (Yamnaya-like) Afanasievo to Central and East Asian-like populations. In red circles, samples with best fit for Andronovo-like ancestry. In green circles, samples with Han-related admixture.

M15-2 (with Han-related ancestry) is of the rare haplogroup Q1a-M120, while the samples with highest Steppe_MLBA-related ancestry are of hg. R1b-PH155, which points to their recent origin among Yuezhi, or to Hun-related populations showing an admixture related to the proto-historic nomads of the Gansu and Qinghai grasslands.

The expansion of Chemurchek-related peoples was probably associated more with hg. Q1a (dubious if it’s a Pre-ISOGG 2017 nomenclature, hence possibly Q1b), a haplogroup that might be found in Khvalynsk as a “significant minority” according to Anthony (2019), and it might also be attested in sampled individuals from Afanasievo in its late phase. This might be, therefore, a case similar to the early expansion of Indo-Europeans with R1b-V1636 lineages through the Volga – North Caucasus region, and of the later expansion with I2a-L699 lineages into the Balkans.

Haplogroup Q1a2-M25 is found in individual X3, whose Steppe ancestry is likely a combination of Afanasievo plus Andronovo-like ancestry heavily admixed with Hezhen/Ulchi-like populations, in line with the expected recent contacts with the neighbouring Xiongnu, Yuezhi, and other population movements affecting eastern Xinjiang.

Sample M4, which packs the most Afanasievo-like ancestry, is of hg. R1a-Z645, which – like sample M8R1 of hg. O – is most likely related to haplogroup resurgence events of local populations, which left the predominant Afanasievo-like admixture brought by builders of stone burials essentially intact, evidenced by the almost 100% of R1a found in the Xiaohe cemetery – and in most of the early Andronovo horizon – and among expanding Kangju and Wusun, as well as by the prevalence of hg. O among sampled East Asian populations.

A question that will only be answered with more samples is how and when the prevalent R1b-L23 and Q1b lineages among Afanasievo-related peoples began to be replaced to reach the high variability seen in Shirenzigou. Given the pastoralist nature of peoples around Tian Shan, the succeeding expansions of Proto-Tocharians, and the late isolation of different Common Tocharian groups, it is more than likely that this variability represents a late and local phenomenon within Xinjiang itself.

tocharians-antiquity
Peoples of Xinjiang during Antiquity. See full culture and ancient DNA maps.

Conclusion

Tocharians are one of the main pillars that confirm the Late Proto-Indo-European homeland of the R1b-rich populations of the Don-Volga region. There is already:

Just like the East Bell Beaker expansion from Yamnaya Hungary has confirmed that Corded Ware peoples did not partake in spreading Indo-European languages (spreading Uralic languages instead), data on the expansion of Tocharian speakers from Afanasievo to the Tian Shan was always there; population genomics is merely helping to connect the dots.

In summary, genetic research is supporting the expected linguistic expansions of the Neolithic and Bronze Age step by step, slowly but surely.

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