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

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

N1c-L392 associated with expanding Turkic lineages in Siberia

haplogroup-n1c-tat

Second in popularity for the expansion of haplogroup N1a-L392 (ca. 4400 BC) is, apparently, the association with Turkic, and by extension with Micro-Altaic, after the Uralic link preferred in Europe; at least among certain eastern researchers.

New paper in a recently created journal, by the same main author of the group proposing that Scythians of hg. N1c were Turkic speakers: On the origins of the Sakhas’ paternal lineages: Reconciliation of population genetic / ancient DNA data, archaeological findings and historical narratives, by Tikhonov, Gurkan, Demirdov, and Beyoglu, Siberian Research (2019).

Interesting excerpts:

According to the views of a number of authoritative researchers, the Yakut ethnos was formed in the territory of Yakutia as a result of the mixing of people from the south and the autochthonous population [34].

These three major Sakha paternal lineages may have also arrived in Yakutia at different times and/ or from different places and/or with a difference in several generations instead, or perhaps Y-chromosomal STR mutations may have taken place in situ in Yakutia. Nevertheless, the immediate common ancestor(s) from the Asian Steppe of these three most prevalent Sakha Y-chromosomal STR haplotypes possibly lived during the prominence of the Turkic Khaganates, hence the near-perfect matches observed across a wide range of Eurasian geography, including as far as from Cyprus in the West to Liaoning, China in the East, then Middle Lena in the North and Afghanistan in the South (Table 3 and Figure 5). There may also be haplotypes closely-related to ‘the dominant Elley line’ among Karakalpaks, Uzbeks and Tajiks, however, limitations in the loci coverage for the available dataset (only eight Y-chromosomal STR loci) precludes further conclusions on this matter [25].

yakutia-haplogroup-n1c
17-loci median-joining network analysis of the original/dominant Elley, Unknown and Omogoy Y-chromosomal STR haplotypes with the YHRD matches from outside Yakutia populations.

According to the results presented here, very similar Y-STR haplotypes to that of the original Elley line were found in the west: Afghanistan and northern Cyprus, and in the east: Liaoning Province, China and Ulaanbaator, Northern Mongolia. In the case of the dominant Omogoy line, very closely matching haplotypes differing by a single mutational step were found in the city of Chifen of the Jirin Province, China. The widest range of similar haplotypes was found for the Yakut haplotype Unknown: In Mongolia, China and South Korea. For instance, haplotypes differing by a single step mutation were found in Northern Mongolia (Khalk, Darhad, Uryankhai populations), Ulaanbaator (Khalk) and in the province of Jirin, China (Han population).

n1c-uralic-altaic-siberia
14-loci median-joining network analysis for the original/dominant Elley (Ell), Unknown Clan
(Vil), Omogoy (Omo), Eurasian (Eur) and Xiongnu (Xuo) Y-chromosomal STR haplotypes and that for a representative ancient DNA sample (Ch0 or DSQ04) from the Upper Xiajiadian Culture
recovered from the Inner Mongolia Autonomous Region, China.

Notably, Tat-C-bearing Y-chromosomes were also observed in ancient DNA samples from the 2700-3000 years-old Upper Xiajiadian culture in Inner Mongolia, as well as those from the Serteya II site at the Upper Dvina region in Russia and the ‘Devichyi gory’ culture of long barrow burials at the Nevel’sky district of Pskovsky region in Russia. A 14-loci Y-chromosomal STR median-joining network of the most prevalent Sakha haplotypes and a Tat-C-bearing haplotype from one of the ancient DNA samples recovered from the Upper Xiajiadian culture in Inner Mongolia (DSQ04) revealed that the contemporary Sakha haplotype ‘Xuo’ (Table 2, Haplotype ID “Xuo”) classified as that of ‘the Xiongnu clan’ in our current study, was the closest to the ancient Xiongnu haplotype (Figure 6). TMRCA estimate for this 14-loci Y-chromosomal STR network was 4357 ± 1038 years or 2341 ± 1038 BCE, which correlated well with the Upper Xiajiadian culture that was dated to the Late Bronze Age (700-1000 BCE).

eurasian-n-subclades
Geographical location of ancient samples belonging to major clade N of the Y-chromosome.

NOTE. Also interesting from the paper seems to be the proportion of E1b1b among admixed Russian populations, in a proportion similar to R1a or I2a(xI2a1).

It is tempting to associate the prevalent presence of N1c-L392 in ancient Siberian populations with the expansion of Altaic, by simplistically linking the findings (in chronological order) near Lake Baikal (Damgaard et al. 2018), Upper Xiajiadian (Cui et al. 2013), among Khövsgöl (Jeong et al. 2018), in Huns (Damgaard et al. 2018), and in Mongolic-speaking Avars (Csáky et al. 2019).

However, its finding among Palaeo-Laplandic peoples in the Kola peninsula ca. 1500 BC (Lamnidis et al. 2018) and among Palaeo-Siberian populations near the Yana River (Sikora et al. 2018) ca. AD 1200 should be enough to accept the hypothesis of ancestral waves of expansion of the haplogroup over northern Eurasia, with acculturation and further expansions in the different regions since the Iron Age (see more on its potential expansion waves).

Also, a simple look at the TMRCA and modern distribution was enough to hypothesize long ago the lack of connection of N1c-L392 with Altaic or Uralic peoples. From Ilumäe et al. (2016):

Previous research has shown that Y chromosomes of the Turkic-speaking Yakuts (Sakha) belong overwhelmingly to hg N3 (formerly N1c1). We found that nearly all of the more than 150 genotyped Yakut N3 Y chromosomes belong to the N3a2-M2118 clade, just as in the Turkic-speaking Dolgans and the linguistically distant Tungusic-speaking Evenks and Evens living in Yakutia (Table S2). Hence, the N3a2 patrilineage is a prime example of a male population of broad central Siberian ancestry that is not intrinsic to any linguistically defined group of people. Moreover, the deepest branch of hg N3a2 is represented by a Lebanese and a Chinese sample. This finding agrees with the sequence data from Hallast et al., where one Turkish Y chromosome was also assigned to the same sub-clade. Interestingly, N3a2 was also found in one Bhutan individual who represents a separate sub-lineage in the clade. These findings show that although N3a2 reflects a recent strong founder effect primarily in central Siberia (Yakutia, Sakha), the sub-clade has a much wider distribution area with incidental occurrences in the Near East and South Asia.

haplogroup-n1a-M2118
Frequency-Distribution Maps of Individual Sub-clades of hg N3a2, by Ilumäe et al. (2016).

The most striking aspect of the phylogeography of hg N is the spread of the N3a3’6-CTS6967 lineages. Considering the three geographically most distant populations in our study—Chukchi, Buryats, and Lithuanians—it is remarkable to find that about half of the Y chromosome pool of each consists of hg N3 and that they share the same sub-clade N3a3’6. The fractionation of N3a3’6 into the four sub-clades that cover such an extraordinarily wide area occurred in the mid-Holocene, about 5.0 kya (95% CI = 4.4–5.7 kya). It is hard to pinpoint the precise region where the split of these lineages occurred. It could have happened somewhere in the middle of their geographic spread around the Urals or further east in West Siberia, where current regional diversity of hg N sub-lineages is the highest (Figure 1B). Yet, it is evident that the spread of the newly arisen sub-clades of N3a3’6 in opposing directions happened very quickly. Today, it unites the East Baltic, East Fennoscandia, Buryatia, Mongolia, and Chukotka-Kamchatka (Beringian) Eurasian regions, which are separated from each other by approximately 5,000–6,700 km by air. N3a3’6 has high frequencies in the patrilineal pools of populations belonging to the Altaic, Uralic, several Indo-European, and Chukotko-Kamchatkan language families. There is no generally agreed, time-resolved linguistic tree that unites these linguistic phyla. Yet, their split is almost certainly at least several millennia older than the rather recent expansion signal of the N3a3’6 sub-clade, suggesting that its spread had little to do with linguistic affinities of men carrying the N3a3’6 lineages.

haplogroup_n3a3
Frequency-Distribution Maps of Individual Subclade N3a3 / N1a1a1a1a1a-CTS2929/VL29.

It was thus clear long ago that N1c-L392 lineages must have expanded explosively in the 5th millennium through Northern Eurasia, probably from a region to the north of Lake Baikal, and that this expansion – and succeeding ones through Northern Eurasia – may not be associated to any known language group until well into the common era.

Related

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

dzudzuana_pca-large

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

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

anatolia-neolithic-steppe-eneolithic
Image modified from Wang et al. (2018). Marked are in orange: equivalent Steppe_Maykop ADMIXTURE; in red, approximate limit of Anatolia_Neolithic ancestry found in Yamna populations; in blue, Corded Ware-related groups. “Modelling results for the Steppe and Caucasus cluster. Admixture proportions based on (temporally and geographically) distal and proximal models, showing additional Anatolian farmer-related ancestry in Steppe groups as well as additional gene flow from the south in some of the Steppe groups as well as the Caucasus groups.”

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

1. Samara to Early Khvalynsk

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

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

PCA-caucasus-steppe-samara

This is what Steppe_Maykop looks like, different from Steppe_Eneolithic:

steppe-maykop-admixture

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

2. Early Khvalynsk expansion

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

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

PCA-khvalynsk-steppe

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

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

3. Proto-Corded Ware expansion

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

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

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

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

PCA-sredni-stog-steppe

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

steppe-ancestry-admixture-sredni-stog

4. Repin / Early Yamna expansion

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

afanasevo-admixture

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

PCA-repin-yamna

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

yamnaya-admixture

5. Corded Ware

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

PCA-latvia-ln-steppe

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

sintashta-poltavka-andronovo-admixture

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

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

steppe-ancestry-admixture-latvia

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

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

Conclusion

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

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

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

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

See also

Related

Iron Age bottleneck of the Proto-Fennic population in Estonia

tarand-graves-estonia-early-late

Demographic data and figures derived from Estonian Iron Age graves, by Raili Allmäe, Papers on Anthropology (2018) 27(2).

Interesting excerpts (emphasis mine):

Introduction

Inhumation and cremation burials were both common in Iron Age Estonia; however, the pattern which burials were prevalent has regional as well temporal peculiarities. In Estonia, cremation burials appear in the Late Bronze Age (1100–500 BC), for example, in stone-cist graves and ship graves, although inhumation is still characteristic of the period [28, 18]. Cremation burials have occasionally been found beneath the Late Bronze Age cists and the Early Iron Age (500 BC–450 AD) tarand graves [30, 28]. In south-eastern Estonia, including Setumaa, the tradition to bury cremated human remains in pit graves also appeared in the Bronze Age and lasted during the Pre-Roman period (500 BC–50 AD) and the Roman Iron Age (50–450 AD), and even up to the medieval times [30, 23, 33, 9]. During the Early Iron Age, cremations appear in cairn graves and have occasionally been found in many Pre-Roman early tarand graves where they appear with inhumations [27, 28, 19, 20, 21, 22, 24]. In Roman Iron Age tarand graves, cremation as well inhumation were practiced [28, 36, 37]; however, cremation was the prevailing burial practice during the Roman Iron Age, for example, in tarand graves in south-eastern Estonia [30, 28]. Roman Iron Age (50 AD–450 AD) burial sites have not been found in continental west Estonia [28, 38]). At the beginning of the Middle Iron Age (450–800 AD), burial sites, for example stone graves without a formal structure, like Maidla I, Lihula and Ehmja ‘Varetemägi’, appear in Läänemaa, west Estonia; in these graves cremations as well inhumations have been found [39, 48]. Like underground cremation burial, the stone grave without a formal structure was the most common grave type during the Late Iron Age (800– 1200 AD) in west Estonia [39, 35, 48]. In south-eastern and eastern Estonia, sand barrows with cremation burials appeared at the beginning of the Middle Iron Age. Cremation barrows are attributed to the Culture of Long Barrows and are most numerous in the villages Laossina and Rõsna in northern Setomaa, on the western shore of Lake Peipsi [8, 48]. Apparently during the Iron Age, the practiced burial customs varied in Estonia.

cist-grave-tarand
Typical prehistoric Estonian graves. Top: Cist-graves common during the Bronze Age, by Terker (GNU FDL 1.2). Bottom: Tarand graves of the Iron Age, by Marika Mägi (2017)

Abstract:

Three Iron Age cremation graves from south-eastern Estonia and four graves including cremations as well inhumations from western Estonia were analysed by osteological and palaeodemographic methods in order to estimate the age and sex composition of burial sites, and to propose some possible demographic figures and models for living communities.

The crude birth/death rate estimated on the basis of juvenility indices varied between 55.1‰ and 60.0‰ (58.5‰ on average) at Rõsna village in south-eastern Estonia in the Middle Iron Age. The birth/death rates based on juvenility indices for south eastern graves varied to a greater degree. The estimated crude birth/death rate was somewhat lower (38.9‰) at Maidla in the Late Iron Age and extremely high (92.1‰) at Maidla in the Middle Iron Age, which indicates an unsustainable community. High crude birth/death rates are also characteristic of Poanse tarand graves from the Pre-Roman Iron Age – 92.3‰ for the 1st grave and 69.6‰for the 2nd grave. Expectedly, newborn life expectancies are extremely low in both communities – 10.8 years at Poanse I and 14.4 years at Poanse II. Most likely, both Maidla I and Poanse I were unsustainable communities.

tarand-graves-estonia
Locations of the investigated Estonian Iron Age graves. Map by R. Allmäe

According to the main model where the given period of grave usage is 150 years, the burial grounds were most likely exploited by communities of 3–14 people. In most cases, this corresponds to one family or household. In comparison with other graves, Maidla II stone grave in western Estonia and Rõsna-Saare I barrow cemetery in south-eastern Estonia could have been used by a somewhat larger community, which may mean an extended family, a larger household or usage by two nuclear families.

More papers on the same subject by the author – who participated in the recent Mittnik et al. (2018) paper – include Observations On Estonian Iron Age Cremations (2013), and The demography of Iron Age graves in Estonia (2014).

Fast life history in Iron Age Estonia

While the demographic situation in the Gulf of Finland during the Iron Age is not well known – and demography is always difficult to estimate based on burials, especially when cremation is prevalent – , there is a clear genetic bottleneck in Finns, which has been estimated precisely to this period, coincident with the expansion of Proto-Fennic.

estonian-pca
PCA of Estonian samples from the Bronze Age, Iron Age and Medieval times. Tambets et al. (2018, upcoming).

The infiltration of N1c lineages in Estonia – the homeland of Proto-Fennic – happened during the Iron Age – as of yet found in 3 out of 5 sampled Tarand graves – , while the previous period was dominated by 100% R1a and Corded Ware + Baltic HG ancestry. With the Iron Age, a slight shift towards Corded Ware ancestry can be seen, which probably signals the arrival of warrior-traders from the Alanino culture, close to the steppe. They became integrated through alliances and intermarriages in a culture of chiefdoms dominated by hill forts. Their origin in the Mid-Volga area is witnessed by their material culture, such as Tarand-like graves (read here a full account of events).

This new political structure, reminiscent of the chiefdom system in Sintashta (with a similar fast life history causing a bottleneck of R1a-Z645 lineages), coupled with the expansion of Fennic (and displaced Saamic) peoples to the north, probably caused the spread of N1c-L392 among Finnic peoples. The linguistic influence of these early Iron Age trading movements from the Middle Volga region can be seen in similarities between Fennic and Mordvinic, which proves that the Fenno-Saamic community was by then not only separated linguistically, but also physically (unlike the period of long-term Palaeo-Germanic influence, where loanwords could diffuse from one to the other).

NOTE. Either this, or the alternative version: an increase in Corded Ware ancestry in Estonia during the Iron Age marks the arrival of the first Fennic speakers ca. 800 BC or later, splitting from Mordvinic? A ‘Mordvin-Fennic’ group in the Volga, of mainly Corded Ware ancestry…?? Which comes in turn from a ‘Volga-Saamic’ population of Siberian ancestry in the Artic region??? And, of course, Palaeo-Germanic widely distributed in North-Eastern Europe with R1a during the Bronze Age! Whichever model you find more logical.

Related

Corded Ware—Uralic (I): Differences and similarities with Yamna

indo-european-uralic-migrations-corded-ware

This is the first of four posts on the Corded Ware—Uralic identification:

I was reading The Bronze Age Landscape in the Russian Steppes: The Samara Valley Project (2016), and I was really surprised to find the following excerpt by David W. Anthony:

The Samara Valley links the central steppes with the western steppes and is a north-south ecotone between the pastoral steppes to the south and the forest-steppe zone to the north [see figure below]. The economic contrast between pastoral steppe subsistence, with its associated social organizations, and forest-zone hunting and fishing economies probably explains the shifting but persistent linguistic border between forest-zone Uralic languages to the north (today largely displaced by Russian) and a sequence of steppe languages to the south, recently Turkic, before that Iranian, and before that probably an eastern dialect of Proto-Indo-European (Anthony 2007). The Samara Valley represents several kinds of borders, linguistic, cultural, and ecological, and it is centrally located in the Eurasian steppes, making it a critical place to examine the development of Eurasian steppe pastoralism.

uralic-languages-forest-zone-volga
Language map of the middle Volga-Ural region. After “Geographical Distribution of the Uralic Languages” by Finno-Ugrian Society, Helsinki, 1993.

Khokhlov (translated by Anthony) further insists on the racial and ethnic divide between both populations, Abashevo to the north, and Poltavka to the south, during the formation of the Abashevo – Sintashta-Potapovka community that gave rise to Proto-Indo-Iranians:

Among all cranial series in the Volga-Ural region, the Potapovka population represents the clearest example of race mixing and probably ethnic mixing as well. The cultural advancements seen in this period might perhaps have been the result of the mixing of heterogeneous groups. Such a craniometric observation is to some extent consistent with the view of some archaeologists that the Sintashta monuments represent a combination of various cultures (principally Abashevo and Poltavka, but with other influences) and therefore do not correspond to the basic concept of an archaeological culture (Kuzmina 2003:76). Under this option, the Potapovka-Sintashta burial rite may be considered, first, a combination of traits to guarantee the afterlife of a selected part of a heterogeneous population. Second, it reflected a kind of social “caste” rather than a single population. In our view, the decisive element in shaping the ethnic structure of the Potapovka-Sintashta monuments was their extensive mobility over a fairly large geographic area. They obtained knowledge of various cultures from the populations with whom they interacted.

steppe-lmba-sintashta-potapovka-filatovka
Late Middle Bronze Age cultures with the Proto-Indo-Iranian Sintashta-Potapovka-Filatovka group (shaded). After Anthony (2007 Figure 15.5), from Anthony (2016).

Interesting is also this excerpt about the predominant population in the Abashevo – Sintashta-Potapovka admixture (which supports what Chetan said recently, although this does not seemed backed by Y-DNA haplogroups found in the richest burials), coupled with the sign of incoming “Uraloid” peoples from the east, found in both Sintashta and eastern Abashevo:

The socially dominant anthropological component was Europeoid, possibly the descendants of Yamnaya. The association of craniofacial types with archaeological cultures in this period is difficult, primarily because of the small amount of published anthropological material of the cultures of steppe and forest belt (Balanbash, Vol’sko-Lbishche) and the eastern and southern steppes (Botai-Tersek). The crania associated with late MBA western Abashevo groups in the Don-Volga forest zone were different from eastern Abashevo in the Urals, where the expression of the Old Uraloid craniological complex was increased. Old Uraloid is found also on a single skull of Vol’sko-Lbishche culture (Tamar Utkul VII, Kurgan 4). Potentially related variants, including Mongoloid features, could be found among the Seima-Turbino tribes of the forest-steppe zone, who mixed with Sintashta and Abashevo. In the Sintashta Bulanova cemetery from the western Urals, some individuals were buried with implements of Seima-Turbino type (Khalyapin 2001; Khokhlov 2009; Khokhlov and Kitov 2009). Previously, similarities were noted between some individual skulls from Potapovka I and burials of the much older Botai culture in northern Kazakhstan (Khokhlov 2000a). Botai-Tersek is, in fact, a growing contender for the source of some “eastern” cranial features.

khvalynsk-yamna-srubna-facial-reconstruction
Facial reconstructions based on skulls from (a) Khvalynsk II Grave 24, a young adult male; (b) Poludin Grave 6, Yamnaya culture, a mature male (both by A. I. Nechvaloda); and (c) Luzanovsky cemetery, Srubnaya culture (by L. T. Yablonsky). In Khokhlov (2016).

The wave of peoples associated with “eastern” features can be seen in genetics in the Sintashta outliers from Narasimhan et al. (2018), and it probably will be eventually seen in Abashevo, too. These may be related to the Seima-Turbino international network – but most likely it is directly connected to Sintashta through the starting Andronovo and Seima-Turbino horizons, by admixing of prospective groups and small-scale back-migrations.

Corded Ware – Yamna similarities?

So, if peoples of north-eastern Europe have been assumed for a long time to be Uralic speakers, what is happening with the Corded Ware = IE obsession? Is it Gimbutas’ ghost possessing old archaeologists? Probably not.

It is about certain cultural similarities evident at first sight, which have been traditionally interpreted as a sign of cultural diffusion or migration. Not dissimilar to the many Bell Beaker models available, where each archaeologist is pushing certain differences, mixing what seemed reasonable, what still might seem reasonable, and what certainly isn’t anymore after the latest ancient DNA data.

kurgan-expansion
“European dialect” expansion of Proto-Indo-European according to Gimbutas (1963)

The initial models of Gimbutas, Kristiansen, or Anthony – which are known to many today – were enunciated in the infancy of archaeological studies in the regions, during and just after the fall of the USSR, and before many radiocarbon dates that we have today were published (with radiocarbon dating being still today in need of refinement), so it is only logical that gross mistakes were made.

We have similar gross mistakes related to the origins of Bell Beakers, and studying them was certainly easier than studying eastern data.

  • Gimbutas believed – based mainly on Kurgan-like burials – that Bell Beaker formed from a combination of Yamna settlers with the Vučedol culture, so she was not that far from the truth.
  • The expansion of Corded Ware from peoples of the North Pontic forest-steppe area, proposed by Gimbutas and later supported also by Kristiansen (1989) as the main Indo-European expansion – , is probably also right about the approximate origins of the culture. Only its ‘Indo-European’ nature is in question, given the differences with Khvalynsk and Yamna evolution.
  • Anthony only claimed that Yamna migrants settled in the Balkans and along the Danube into the Hungarian steppes. He never said that Corded Ware was a Yamna offshoot until after the first genetic papers of 2015 (read about his newest proposal). He initially claimed that only certain neighbouring Corded Ware groups “adopted” Indo-European (through cultural diffusion) because of ‘patron-client’ relationships, and was never preoccupied with the fate of Corded Ware and related cultures in the east European forest zone and Finland.

So none of them was really that far from the true picture; we might say a lot people are more way off the real picture today than the picture these three researchers helped create in the 1990s and 2000s. Genetics is just putting the last nail in the coffin of Corded Ware as a Yamna offshoot, instead of – as we believed in the 2000s – to Vučedol and Bell Beaker.

So let’s revise some of these traditional links between Corded Ware and Yamna with today’s data:

Archaeology

Even more than genetics – at least until we have an adequate regional and temporary sampling – , archaeological findings lead what we have to know about both cultures.

It is essential to remember that Corded Ware, starting ca. 3000/2900 BC in east-central Europe, has been proposed to be derived from Early Yamna, which appeared suddenly in the Pontic-Caspian steppes ca. 3300 BC (probably from the late Repin expansion), and expanded to the west ca. 3000.

Early Yamna is in turn identified as the expanding Late Proto-Indo-European community, which has been confirmed with the recent data on Afanasevo, Bell Beaker, and Sintashta-Potapovka and derived cultures.

The question at hand, therefore, is if Corded Ware can be considered an offshoot of the Late PIE community, and thus whether the CWC ethnolinguistic community – proven in genetics to be quite homogeneous – spoke a Late PIE dialect, or if – alternatively – it is derived from other neighbouring cultures of the North Pontic region.

NOTE. The interpretation of an Indo-Slavonic group represented by a previous branching off of the group is untenable with today’s data, since Indo-Slavonic – for those who support it – would itself be a branch of Graeco-Aryan, and Palaeo-Balkan languages expanded most likely with West Yamna (i.e. R1b-L23, mainly R1b-Z2103) to the south.

The convoluted alternative explanation would be that Corded Ware represents an earlier, Middle PIE branch (somehow carrying R1a??) which influences expanding Late PIE dialects; this has been recently supported by Kortlandt, although this simplistic picture also fails to explain the Uralic problem.

Kurgans: The Yamna tradition was inherited from late Repin, in turn inherited from Khvalynsk-Novodanilovka proto-Kurgans. As for the CWC tradition, it is unclear if the tumuli were built as a tradition inherited from North and West Pontic cultures (in turn inherited or copied from Khvalynsk-Novodanilovka), such as late Trypillia, late Kvityana, late Dereivka, late Sredni Stog; or if they were built because of the spread of the ‘Transformation of Europe’, set in motion by the Early Yamna expansion ca. 3300-3000 BC (as found in east-central European cultures like Coţofeni, Lizevile, Șoimuș, or the Adriatic Vučedol). My guess is that it inherits an older tradition than Yamna, with an origin in east-central Europe, because of the mound-building distribution in the North Pontic area before the Yamna expansion, but we may never really know.

pit-graves-central-europe-cwc
Distribution of Pit-Grave burials west of the Black Sea likely dating to the 2nd half of the IVth millennium BC (triangles: side-crouched burials; filled circles: supine extended burials; open circles: suspected). Frînculeasa, Preda, and Heyd (2015)

Burial rite: Yamna features (with regional differences) single burials with body on its back, flexed upright knees, poor grave goods, common orientation east-west (heads to the west) inherited from Repin, in turn inherited from Khvalynsk-Novodanilovka. CWC tradition – partially connected to Złota and surrounding east-central European territories (in turn from the Khvalynsk-Novodanilovka expansion) – features single graves, body in fetal position, strict gender differentiation – men on the right, women on the left -, looking to the south, graves with standardized assemblages (objects representing affirmation of battle, hunting, and feasting). The burial rites clearly represent different ideologies.

pit-grave-burial-schemes
Left: Pit-Grave burial types expanded with Khvalynsk-Novodanilovka. Right: Pit-Grave burial types associated with the Yamna expansion and influence. Frînculeasa, Preda, and Heyd (2015)

Corded decoration: Corded ware decoration appears in the Balkans during the 5th millennium, and represents a simple technique whereby a cord is twisted, or wrapped around a stick, and then pressed directly onto the fresh surface of a vessel leaving a characteristic decoration. It appears in many groups of the 5th and 4th millennium BC, but it was Globular Amphorae the culture which popularized the drinking vessels and their corded ornamentation. It appears thus in some regional groups of Yamna, but it becomes the standard pottery only in Corded Ware (especially with the A-horizon), which shows continuity with GAC pottery.

corded-ware-first-horizon
Origins of the first Corded Ware horizon (5th millennium BC) after the Khvalynsk-Novodanilovka expansion. Corded Ware (circles) and horse-head scepters (rectangles) and other steppe elements (triangles). Image from Bulatović (2014).

Economy: Yamna expands from Repin (and Repin from Khvalynsk-Novodanilovka) as a nomadic or semi-nomadic purely pastoralist society (with occasional gathering of wild seeds), which naturally thrives in the grasslands of the Pontic-Caspian, lower Danube and Hungarian steppes. Corded Ware shows agropastoralism (as late Eneolithic forest-steppe and steppe groups of eastern Europe, such as late Trypillian, TRB, and GAC groups), inhabits territories north of the loess line, with heavy reliance of hunter-gathering depending on the specific region.

Cattle herding: Interestingly, both west Yamna and Corded Ware show more reliance on cattle herding than other pastoralist groups, which – contrasted with the previous Eneolithic herding traditions of the Pontic-Caspian steppe, where sheep-goats predominate – make them look alike. However, the cattle-herding economy of Yamna is essential for its development from late Repin and its expansion through the steppes (over western territories practising more hunter-gathering and sheep-goat herding economy), and it does not reach equally the Volga-Ural region, whose groups keep some of the old subsistence economy (read more about the late Repin expansion). Corded Ware, on the other hand, inherits its economic strategy from east European groups like TRB, GAC, and especially late Trypillian communities, showing a predominance of cattle herding within an agropastoral community in the forest-steppe and forest zones of Volhynia, Podolia, and surrounding forest-steppe and forest regions.

yamna-scheme
Scheme of interlinked socio-economic-ideological innovations forming the Yamnaya. Frînculeasa, Preda, and Heyd (2015)

Horse riding: Horse riding and horse transport is proven in Yamna (and succeeding Bell Beaker and Sintashta), assumed for late Repin (essential for cattle herding in the seas of grasslands that are the steppes, without nearby water sources), quite likely during the Khvalynsk expansion (read more here), and potentially also for Samara, where the predominant horse symbolism of early Khvalynsk starts. Corded Ware – like the north Pontic forest-steppe and forest areas during the Eneolithic – , on the other hand, does not show a strong reliance on horse riding. The high mobility and short-term settlements characteristic of Corded Ware, that are often associated with horse riding by association with Yamna, may or may not be correct, but there is no need for horses to explain their herding economy or their mobility, and the north-eastern European areas – the one which survived after Bell Beaker expansion – did certainly not rely on horses as an essential part of their economy.

NOTE: I cannot think of more supposed similarities right now. If you have more ideas, please share in the comments and I will add them here.

Genetic similarities

EHG: This is the clearest link between both communities. We thought it was related to the expansion of ANE-related ancestry to the west into WHG territory, but now it seems that it will be rather WHG expanding into ANE territory from the Pontic-Caspian region to the east (read more on recent Caucasus Neolithic, on , and on Caucasus HG).

NOTE. Given how much each paper changes what we know about the Palaeolithic, the origin and expansion of the (always developing) known ancestral components and specific subclades (see below) is not clear at all.

CHG: This is the key link between both cultures, which will delimit their interaction in terms of time and space. CHG is intermediate between EHG and Iran N (ca. 8000 BC). The ancestry is thus linked to the Caucasus south of the steppe before the emergence of North Pontic (western) and Don-Volga-Ural (eastern) communities during the Mesolithic. The real question is: when we have more samples from the steppe and the Caucasus during the Neolithic, how many CHG groups are we going to find? Will the new specific ancestral components (say CHG1, CHG2, CHG3, etc.) found in Yamna (from Khvalynsk, in the east) and Corded Ware (probably from the North Pontic forest-steppe) be the same? My guess is, most likely not, unless they are mediated by the Khvalynsk-Novodanilovka expansion (read more on CHG in the Caucasus).

yamnaya-chg-ancestry
Formation of Yamna and CHG contribution, in Damgaard et al. (Science 2018). A 10-leaf model based on combining the models in Fig. S16 and Fig. S19 and re-estimating the model parameters.

WHG/EEF: This is the obvious major difference – known today – in the formation of both communities in the steppe, and shows the different contacts that both groups had at least since the Eneolithic, i.e. since the expansion of Repin with its renewed Y-DNA bottleneck, and probably since before the early Khvalynsk expansion (read more on Yamna-Corded Ware differences contrasting with Yamna-Afanasevo, Yamna-Bell Beaker, and Yamna-Sintashta similarities).

NOTE 1. Some similarities between groups can be seen depending on the sampled region; e.g. Baltic groups show more similarities with southern Pontic-Caspian steppe populations, probably due to exogamy.

yamna-corded-ware-diff-qpgraph
Tested qpGraph model in Tambets et al. (2018). The qpGraph model fitting the data for the tested populations. “Colour codes for the terminal nodes: pink—modern populations (‘Population X’ refers to test population) and yellow—ancient populations (aDNA samples and their pools). Nodes coloured other than pink or yellow are hypothetical intermediate populations. We putatively named nodes which we used as admixture sources using the main recipient among known populations. The colours of intermediate nodes on the qpGraph model match those on the admixture proportions panel.”

NOTE 2. We have this information on the differences in “steppe ancestry” between Yamna and Corded Ware, compared to previous studies, because now we have more samples of neighbouring, roughly contemporaneous Eneolithic groups, to analyse the real admixture processes. This kind of fine scale studies is what is going to show more and more differences between Khvalynsk-Yamna and Sredni Stog-Corded Ware as more data pours in. The evolution of both communities in archaeology and in PCA (see below) is probably witness to those differences yet to be published.

R1: Even though some people try very hard to think in terms of “R1” vs. (Caucasus) J or G or any other upper clade, this is plainly wrong. It is possible, given what we know now, that Q1a2-M242 expanded ANE ancestry to the west ca. 13000 BC, while R1b-P279 expanded WHG ancestry to the east with the expansion of post-Swiderian cultures, creating EHG as a WHG:ANE cline. The role of R1a-M459 is unknown, but it might be related to any of these migrations, or others (plural) along northern Eurasia (read more on the expansion of R1b-P279, on Palaeolithic Q1a2, and on R1a-M417).

NOTE. I am inclined to believe in a speculative Mesolithic-Early Neolithic community involving Eurasiatic movements accross North Eurasia, and Indo-Uralic movements in its western part, with the last intense early Uralic-PIE contacts represented by the forming west (Mariupol culture) and east (Don-Volga-Ural cultures, including Samara) communities developing side by side. Before their known Eneolithic expansions, no large-scale Y-DNA bottleneck is going to be seen in the Pontic-Caspian steppe, with different (especially R1a and R1b subclades) mixed among them, as shown in North Pontic Neolithic, Samara HG, and Khvalynsk samples.

PCA-trypillia-greece-neolithic-outlier-anatolian
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.

Corded Ware and ‘steppe ancestry’

If we take a look at the evolution of Corded Ware cultures, the expansion of Bell Beakers – dominated over most previous European cultures from west to east Europe – influenced the development of the whole European Bronze Age, up to Mierzanowice and Trzciniec in the east.

The only relevant unscathed CWC-derived groups, after the expansion of Sintashta-Potapovka as the Srubna-Andronovo horizon in the Eurasian steppes, were those of the north-eastern European forest zone: between Belarus to the west, Finland to the north, the Urals to the east, and the forest-steppe region to the south. That is, precisely the region supposed to represent Uralic speakers during the Bronze Age.

This inconsistency of steppe ancestry and its relation with Uralic (and Balto-Slavic) peoples was observed shortly after the publication of the first famous 2015 papers by Paul Heggarty, of the Max-Planck Institute for Evolutionary Anthropology (read more):

Haak et al. (2015) make much of the high Yamnaya ancestry scores for (only some!) Indo-European languages. What they do not mention is that those same results also include speakers of other languages among those with the highest of all scores for Yamnaya ancestry. Only these are languages of the Uralic family, not Indo-European at all; and their Yamnaya-ancestry signals are far higher than in many branches of Indo-European in (southern) Europe. Estonian ranks very high, while speakers of the very closely related Finnish are curiously not shown, and nor are the Saami. Hungarian is relevant less directly since this language arrived only c. 900 AD, but also high.

uralic-steppe-ancestry

These data imply that Uralic-speakers too would have been part of the Yamnaya > Corded Ware movement, which was thus not exclusively Indo-European in any case. And as well as the genetics, the geography, chronology and language contact evidence also all fit with a Yamnaya > Corded Ware movement including Uralic as well as Balto-Slavic.

Both papers fail to address properly the question of the Uralic languages. And this despite — or because? — the only Uralic speakers they report rank so high among modern populations with Yamnaya ancestry. Their linguistic ancestors also have a good claim to have been involved in the Corded Ware and Yamnaya cultures, and of course the other members of the Uralic family are scattered across European Russia up to the Urals.

NOTE. Although the author was trying to support the Anatolian hypothesis – proper of glottochronological studies often published from the Max Planck Institute – , the question remains equally valid: “if Proto-Indo-European expands with Corded Ware and steppe ancestry, what is happening with Uralic peoples?”

For my part, I claimed in my draft that ancestral components were not the only relevant data to take into account, and that Y-DNA haplogroups R1a and R1b (appearing separately in CWC and Yamna-Bell Beaker-Afanasevo), together with their calculated timeframes of formation – and therefore likely expansion – did not fit with the archaeological and linguistic description of the spread of Proto-Indo-European and its dialects.

In fact, it seemed that only one haplogroup (R1b-M269) was constantly and consistenly associated with the proposed routes of Late PIE dialectal expansions – like Anthony’s second (Afanasevo) and third (Lower Danube, Balkan) waves. What genetics shows fits seamlessly with Mallory’s association of the North-West Indo-European expansion with Bell Beakers (read here how archaeologists were right).

balanovksy-yamnaya-ancestry
Map of the much beloved steppe (or “Yamnaya”) ancestry in modern populations, by Balanovsky. Modified from Klejn (2017).

More precise inconsistencies were observed after the publication of Olalde et al. (2017) and Mathieson et al. (2017), by Volker Heyd in Kossinna’s smile (2017). Letting aside the many details enumerated (you can read a summary in my latest draft), this interesting excerpt is from the conclusion:

NOTE. An open access ealier draft version of the paper is offered for download by the author.

Simple solutions to complex problems are never the best choice, even when favoured by politicians and the media. Kossinna also offered a simple solution to a complex prehistoric problem, and failed therein. Prehistoric archaeology has been aware of this for a century, and has responded by becoming more differentiated and nuanced, working anthropologically, scientifically and across disciplines (cf. Müller 2013; Kristiansen 2014), and rejecting monocausal explanations. The two aDNA papers in Nature, powerful and promising as they are for our future understanding, also offer rather straightforward messages, heavily pulled by culture-history and the equation of people with culture. This admittedly is due partly to the restrictions of the medium that conveys them (and despite the often relevant additional detail given as supplementary information, which is unfortunately not always given full consideration).

While I have no doubt that both papers are essentially right, they do not reflect the complexity of the past. It is here that archaeology and archaeologists contributing to aDNA studies find their role; rather than simply handing over samples and advising on chronology, and instead of letting the geneticists determine the agenda and set the messages, we should teach them about complexity in past human actions and interactions. If accepted, this could be the beginning of a marriage made in heaven, with the blessing smile of Gustaf Kossinna, and no doubt Vere Gordon Childe, were they still alive, in a reconciliation of twentieth- and twenty-first-century approaches. For us as archaeologists, it could also be the starting point for the next level of a new archaeology.

heyd-yamnaya-expansion
Main distribution of Yamnaya kurgans in the Pontic-Caspian steppe of modern day Russia, Ukraine, and Kazakhstan, and its western branch in modern south-east European countries of Romania, Bulgaria, Serbia, and Hungary, with numbers of excavated kurgans and graves given. Picture: Volker Heyd (2018).

The question was made painfully clear with the publication of Olalde et al. (2018) & Mathieson et al. (2018), where the real route of Yamna expansion into Europe was now clearly set through the steppes into the Carpathian basin, later expanded as Bell Beakers.

This has been further confirmed in more recent papers, such as Narasimhan et al. (2018), Damgaard et al. (2018), or Wang et al. (2018), among others.

However, the discussion is still dominated by political agendas based on prevalent Y-DNA haplogroups in modern countries and ethnic groups.

Related

Mitogenomes show continuity of Neolithic populations in Southern India

New paper (behind paywall) Neolithic phylogenetic continuity inferred from complete mitochondrial DNA sequences in a tribal population of Southern India, by Sylvester et al. Genetica (2018).

This paper used a complete mtDNA genome study of 113 unrelated individuals from the Melakudiya tribal population, a Dravidian speaking tribe from the Kodagu district of Karnataka, Southern India.

Some interesting excerpts (emphasis mine):

Autosomal genetic evidence indicates that most of the ethnolinguistic groups in India have descended from a mixture of two divergent ancestral populations: Ancestral North Indians (ANI) related to People of West Eurasia, the Caucasus, Central Asia and the Middle East, and Ancestral South Indians (ASI) distantly related to indigenous Andaman Islanders (Reich et al. 2009). It is presumed that proto-Dravidian language, most likely originated in Elam province of South Western Iran, and later spread eastwards with the movement of people to the Indus Valley and later the subcontinent India (McAlpin et al. 1975; Cavalli-Sforza et al. 1988; Renfrew 1996; Derenko et al. 2013). West Eurasian haplogroups are found across India and harbor many deep-branching lineages of Indian mtDNA pool, and most of the mtDNA lineages of Western Eurasian ancestry must have a recent entry date less than 10 Kya (Kivisild et al. 1999a). The frequency of these lineages is specifically found among the higher caste groups of India (Bamshad et al. 1998, 2001; Basu et al. 2003) and many caste groups are direct descendants of Indo-Aryan immigrants (Cordaux et al. 2004). These waves of various invasions and subsequent migrations resulted in major demographic expansions in the region, which added new languages and cultures to the already colonized populations of India. Although previous genetic studies of the maternal gene pools of Indians had revealed a genetic connection between Iranian populations and the Arabian Peninsula, likely the result of both ancient and recent gene flow (Metspalu et al. 2004; Terreros et al. 2011).

mtdna-dravidian-south

Haplogroup HV14

mtDNA haplogroup HV14 has prominence in North/Western Europe, West Eurasia, Iran, and South Caucasus to Central Asia (Malyarchuk et al. 2008; Schonberg et al. 2011; Derenko et al. 2013; De Fanti et al. 2015). Although Palanichamy identified haplogroup HV14a1 in three Indian samples (Palanichamy et al. 2015), it is restricted to limited unknown distribution. In the present study, by the addition of considerable sequences from the Melakudiya population, a unique novel subclade designated as HV14a1b was found with a high frequency (43%) allowed us to reveal the earliest diverging sequences in the HV14 tree prior to the emergence of HV14a1b in Melakudiya. (…) The coalescence age for haplogroup HV14 in this study is dated ~ 16.1 ± 4.2 kya and the founder age of haplogroup HV14 in Melakudiya tribe, which is represented by a novel clade HV14a1b is ~ 8.5 ± 5.6 kya

hv14-mtdna-haplogroup
Maximum Parsimonious tree of complete mitogenomes constructed using 38 sequences from Melakudiya tribe and 11 previously published sequences belonging to haplogroup HV14 [Supplementary file Table S2] Suffixes @ indicate back mutation, a plus sign (+) an insertion. Control region mutations are underlined, and synonymous transitions are shown in normal font and non-synonymous mutations are shown in bold font. Coalescence ages (Kya) for complete coding region are shown in normal font and synonymous transitions are shown in Italics

Haplogroup U7a3a1a2

The coalescence age of haplogroup U7a3a1a2 dates to ~ 13.3 ± 4.0 kya. (…)

Although, haplogroup U7 has its origin from the Near East and is widespread from Europe to India, the phylogeny of Melakudiya tribe with subclade U7a3a1a2 clusters with populations of India (caste and tribe) and neighboring populations (Irwin et al. 2010; Ranaweera et al. 2014; Sahakyan et al. 2017), hint about the in-situ origin of the subclade in India from Indo-Aryan immigrants.

I am not a native English speaker, but this paper looks like it needs a revision by one.

Also – without comparison with ancient DNA – it is not enough to show coalescence age to prove an origin of haplogroup expansion in the Neolithic instead of later bottlenecks. However, since we are talking about mtDNA, it is likely that their analysis is mostly right.

Finally, one thing is to prove that the origin of the Indus Valley Civilization lies (in part) in peoples from the Iranian plateau, and to show with ASI ancestry that they are probably the origin of Proto-Dravidian expansion, and another completely different thing is to prove an Elamo-Dravidian connection.

Since that group is not really accepted in linguistics, it is like talking about proving – through that Iran Neolithic ancestry – a Sumero-Dravidian, or a Hurro-Dravidian connection…

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Polygyny as a potential reason for Y-DNA bottlenecks among agropastoralists

polygyny-estimates

Open access Greater wealth inequality, less polygyny: rethinking the polygyny threshold model by Ross et al. Journal of the Royal Society Interface (2018).

Interesting excerpts, from the discussion (emphasis mine):

We use cross-cultural data and a new mutual mate choice model to propose a resolution to the polygyny paradox. Following Oh et al. [17], we extend the standard polygyny threshold model to a mutual mate choice model that accounts for both female supply to, and male demand for, polygynous matchings, in the light of the importance of, and inequality in, rival and non-rival forms of wealth. The empirical results presented in figures 5 and 6 demonstrate two phenomena that are jointly sufficient to generate a transition to more frequent monogamy among populations with a co-occurring transition to a more unequal, highly stratified, class-based social structure. In such populations, fewer men can cross the wealth threshold required to obtain a second wife, and those who do may be fabulously wealthy, but—because of diminishing marginal fitness returns to increasing number of marriages—do not acquire wives in full proportion to their capacity to support them with rival wealth. Together, these effects reduce the population-level fraction of wives in polygynous marriages.

Our model demonstrates that a low population-level frequency of polygyny will be an equilibrium outcome among fitness maximizing males and females in a society characterized by a large class of wealth-poor peasants and a small class of exceptionally wealthy elite. Our mutual mate choice model thus provides an empirically plausible resolution to the polygyny paradox and the transition to monogamy which co-occurred with the rise of highly unequal agricultural populations.

polygyny-pastoralists
(a) Mean frequency of married women who are married polygynously by production system (+2 s.e.) using the Standard Cross-Cultural Sample [30]. Rates of polygyny are measured with variable ]872, per cent of wives with co-wives. (b) Rates of monogamy and polygyny by production system are measured with variable ]861, the standard polygamy code. Data on subsistence come from variable ]858, categorized subsistence. In general, agricultural populations show reduced rates of polygyny and increased rates of monogamy relative to other subsistence systems. See electronic supplementary material for more information. (c) Gini of wealth by production system in our sample.

The reasons for this decrease in marginal fitness returns are explained as either a) a potential missing of important rival forms of wealth in the statistical model, or b) one or more of the following reasons:

  • [A] male’s time and attention are rival inputs to his own fitness (…) A single rich man will have to defend his 10 wives from nine unmarried men on average.”As the wealth ratio grows even more skewed, this situation could become increasingly difficult to manage (e.g. requiring the use of eunochs to defend harems [74]).
  • A related possibility is that a growing number of unmarried men could socially censure wealthy polygynous males, imposing costs on them that reduce male demand for and/or female supply to polygynous marriage [23,24]. (…)
  • A third possibility is that sexually transmitted infection (STI) burden [22,75] could diminish returns to polygyny, if polygyny enhances infection rates [76,77]. (…)
  • Finally, impediments to cooperation or even outright conflict among co-wives can be greater as the number of wives increases. Interference competition among co-wives could impose significant fitness costs in settings where effective child rearing benefits from cooperation [79,80].(…)
polygyny-agropastoralists
between the Gini coefficient on completed rival wealth and per cent completed female polygyny.

I have previously argued against some reasons traditionally given to explain the replacement of native male populations after migrations (i.e. polygyny, slavery, targeted male extermination, etc.), because I believe that a gradual successful expansion of patrilineal clans over some generations based on wealth alone is enough to explain the obvious Y-DNA bottlenecks that happened in many different prehistoric and historic cultures (especially among steppe pastoralists, including Indo-Europeans).

I realize that I haven’t really used any study to support my opinion, though, and data from modern and ancient pastoralists from different regions seem to contradict it, so maybe ancient DNA can show that Indo-Europeans had often children with more than one woman at the same time. I don’t remember seeing that kind of information in supplementary materials to date. From memory I can think of maybe two or three examples of agnate siblings published, but I doubt the archaeological age estimation (based on simple observation of skeletal remains) combined with radiocarbon age (usually given with broad CI) could be enough to prove a similar age of conception. Maybe a case of many siblings clearly of the same age and from many different mothers in the same burial could be a strong proof of this…

I recently read that theoretical models are actually trusted by no one except for the researchers who propose them, and experimental data are trusted by everyone except for the researchers who worked with them. I cannot agree more. However, we lack information about this question (as far as I know), so we may have to rely on indirect estimations, like the kind of models presented in the paper (or the one proposed for Post-Neolithic Y-chromosome bottlenecks).

The Late Proto-Indo-European word for bride comes from a root meaning ‘drive, lead’, hence literally ‘deportation’, so the bride was transferred from her father’s family to her husband’s house. Marriage was certainly an asymmetrical contract for its members, and the reconstructible word for ‘dowry’ further supports the weaker position of the wife in it. Also, ancient marriage could differ from a family agreement, because marriage by elopement, bride kidnapping or hostage was probably common (more or less socially regulated) for people belonging the same culture. Apart from this, I don’t know about reconstructed linguistic data pointing to polygyny, and I doubt archaeological data alone – without genetics – can help.

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