Indo-European demic diffusion model, 3rd edition

pca-yamna-corded-ware

I have just uploaded the working draft of the third version of the Indo-European demic diffusion model. Unlike the previous two versions, which were published as essays (fully developed papers), this new version adds more information on human admixture, and probably needs important corrections before a definitive edition can be published.

The third version is available right now on ResearchGate and Academia.edu. I will post the PDF at Academia Prisca, as soon as possible:

pca-map-yamna-corded-ware-bell-beaker
Map overlaid by PCA including Yamna, Corded Ware, Bell Beaker, and other samples

Feel free to comment on the paper here, or (preferably) in our forum.

A working version (needing some corrections) divided by sections, illustrated with up-to-date, high resolution maps, can be found (as always) at the official collaborative Wiki website indo-european.info.

Marija Gimbutas and the expansion of the “Kurgan people” based on tumulus-building cultures

An interesting article that I keep stumbling upon, The tumulus in European prehistory: covering the body, housing the soul, by Anthony Harding (2011):

Finally, in Kurgan IV she saw “continuous waves of expansion or raids[that] touched all of northern Europe, the Aegean area, and the east Mediterranean areas possibly as far south as Egypt”. This was the period of the Catacomb Graves, but also the Early Bronze Age rock-cut tombs of the Mediterranean, Vučedol, Bell Beakers in Hungary, the Single Grave culture of the Nordic region. The Kurgan Culture reached Ireland, she remarked in a paper of 1978 “as early as 3500 B.C.” – by which she presumably referred to megalithic mounds covering passage tombs.

(…)

According to Gimbutas, the “Kurgan people” are evidenced by single graves in deep shafts, often in wooden chests (coffins) or stone cists marked by low earth or stone barrows; the dead lay on their backs with legs contracted; they were buried with flint points or arrowheads, figurines depicting horses’ heads, boars tusk ornaments and animal tooth pendants. Human sacrifice was allegedly performed during the funeral ceremonies,and sometimes ritual graves of cattle and other animals were added. This is said to contrast with what Gimbutas called the culture of Old Europe (i.e. the earlier Neolithic of the Balkans), who “betray a concern for the deification of the dead and the construction of monumental works of architecture visible in mortuary houses,grave markings, tumuli, stone rings or stone stelae, and in the large quantity of weapons found in the graves”.

(…)

single-graves-kurgan
The varying burial traditions of the Early Bronze Age in Central and Eastern Europe (Häusler 1977, fig. 1). Circles: tumuli with the “mound edge principle”. Semicircles: tumuli. Stippling: cremation; other symbols represent inhumation graves, divided according to orientation and sex

Can we really associate the practice of mound-building with a specific people, and assume that the spread of the practice indicates the spread of the people? That is one of the “big questions” of European archaeology, and one which a number of papers in the volume address. My own position is that the practice of tumulus building seems so widespread in time and space that it seems hard to associate it with one particular ethnic group – though I can understand how, in the melting pot that was Early Europe, people could believe this to be the case. There are, however, major arguments against the idea, on archaeological grounds alone – which Häusler’s map indicates very clearly. Burial mode and grave form in Copper and Bronze Age Europe was far too variable for any such simplistic correlation. In any case, what are we to make of the appearance of tumuli in such far-flung places as Japan or North America, where tumuli are very common? It was always unlikely that the megalithic tombs of western Europe were to be associated with movements from the steppe 1000 or 2000 years earlier, and nothing that has happened since Gimbutas was writing has changed that situation

Research has corrected Gimbutas’ opinion on the time of spread of Indo-Europeans, on the role of the horse (see e.g. Anthony 2007) in their expansion, and the unrelatedness of the two main central European Chalcolithic archaeological packages: the Corded Ware package that expanded from the Balkans into north-eastern Europe, and the Yamna package (together with the proto-Beaker package) that evolved into the East Bell Beaker culture.

yamna-migration
Extent of migration of the “Yamna package“, from Heyd 2007

However, the shadow of the “Kurgan people” remains in the outdated body of innumerable writings. It was revived with the first attempts at disentangling Europe’s genetic past (based on the role of R1a in expanding Proto-Indo-European).

Particularly strong in that sense is the model set forth by Kristiansen, who was nevertheless aware since his first proposal of the differences between the ‘Kurgan people’ of the steppe and those of the Corded Ware culture, selecting thus an alternative framework of long-lasting human and economic interactions between the “Kurgan people”, the Globular Amphora and Baden cultures with an origin of the culture in the natural region formed between the Upper Dnieper and Vistula rivers.

This idea is continued today, and has been recently linked with the Agricultural Substrate Hypothesis. Originally proposed by Kroonen and linked to the spread of Middle Eastern “R1b1b2” with agriculture, it is now (in Kristiansen et al. 2017 and more recently in Iversen and Kroonen 2017) linked with the expansion of the Corded Ware culture, thus proposing that Pre-Germanic is a branch separated some 6,000 years ago from other branches…

kurgans-corded-ware
Kristiansen’s (1989) schematic presentation of basic principles of burial positions in the Late Neolithic / EBA cultures in northern Eurasia, following to some extent Häusler (1983)

The linguistic proposal is obviously compatible with mainstream archaeological models – which suggest the introduction of Pre-Germanic in Scandinavia with Bell Beaker peoples -, but since the linguistic proposal alone would probably not make such a fuss without the accompanying genetics, I guess this is the right way to publicise it. I doubt linguists really care about genetics, and I really doubt amateur geneticists will read the linguistic proposal, but who cares.

Kristiansen’s traditional model is obviously in contrast with contemporaneous anthropological writings by Anthony, Heyd, or (Gimbutas’ pupil) Mallory, but is nevertheless becoming a resilient tradition in the interpretation of results in studies of human ancestry in Europe.

I doubt that Gimbutas, who was not very fond of tradition, would be proud of this kind of legacy, though…

Featured image: “European dialect” expansion of Proto-Indo-European according to The Indo-Europeans: Archeological Problems, Gimbutas (1963). Observe the similarities of the western European expansion to the recently proposed expansion of R1b lineages with western Yamna and Bell Beaker.

Related:

Spread of Indo-European folktale traditions related to cultural and demic diffusion (using genomic data)

folktale-genomics

New article at PNAS, Inferring patterns of folktale diffusion using genomic data, by Bortoloni et al. (2017).

Abstract:

Observable patterns of cultural variation are consistently intertwined with demic movements, cultural diffusion, and adaptation to different ecological contexts [Cavalli-Sforza and Feldman (1981) Cultural Transmission and Evolution: A Quantitative Approach; Boyd and Richerson (1985) Culture and the Evolutionary Process]. The quantitative study of gene–culture coevolution has focused in particular on the mechanisms responsible for change in frequency and attributes of cultural traits, the spread of cultural information through demic and cultural diffusion, and detecting relationships between genetic and cultural lineages. Here, we make use of worldwide whole-genome sequences [Pagani et al. (2016) Nature 538:238–242] to assess the impact of processes involving population movement and replacement on cultural diversity, focusing on the variability observed in folktale traditions (n = 596) [Uther (2004) The Types of International Folktales: A Classification and Bibliography. Based on the System of Antti Aarne and Stith Thompson] in Eurasia. We find that a model of cultural diffusion predicted by isolation-by-distance alone is not sufficient to explain the observed patterns, especially at small spatial scales (up to ~4,000 km). We also provide an empirical approach to infer presence and impact of ethnolinguistic barriers preventing the unbiased transmission of both genetic and cultural information. After correcting for the effect of ethnolinguistic boundaries, we show that, of the alternative models that we propose, the one entailing cultural diffusion biased by linguistic differences is the most plausible. Additionally, we identify 15 tales that are more likely to be predominantly transmitted through population movement and replacement and locate putative focal areas for a set of tales that are spread worldwide.

I am very interested in folktales and their origins within Proto-Indo-European culture, so the title alone was an immediate click-bait for me. It did, as always, disappoint in its methods and conclusions, but just the idea it proposes is of great interest for future studies.

There are gross limitations in assessing folktales using simply the Aarne-Thompson-Uther Classification without further analysis or explanation, apart from a summary of tales in the supplementary materials.

But their maps and simplistic hypothesized waves of diffusion (‘African origin’, ‘northern Eurasian’, ‘Eastern European’, or ‘Middle-Eastern/Caucasian’) seem to me as if they try to swim with the tide of the current literature regarding the identification of Proto-Indo-European demic diffusion with “steppe admixture” distribution (and ancient language family diffusion in general through admixture), and as such it can only be wrong.

If you just look at actual folktale distribution (black dots) and compare them with prehistoric cultures and ancient Y-DNA distribution, you realize their maps don’t make much sense, and more complex methods (and a clearer idea of what admixture represents) are needed.

If their intention was to get published in a journal of high impact factor, they succeeded, so good for them. I am glad this subject gets more attention. Of course, their conclusions are kept formally in line with the many limitations of their methods, and are the most interesting aspect of the article:

By correcting for the presence of ethnolinguistic barriers, we find that the null model of cultural diffusion predicted by IBD alone cannot explain the observed distribution of folktales across Eurasia. Instead, beyond ~4,000 km, cultural diffusion biased by linguistic barriers exhibits the highest correlation at all geographic bins. At small geographic bins (<4,000 km), population movements and linguistic barriers may be more relevant than geographic proximity, pointing once again at the possible importance of small-scale processes of cultural transmission for testing more specific hypotheses when using genetic evidence. In addition, processes other than simple cultural diffusion may be more relevant for a smaller group of tales shared by pairs of populations that are genetically closer than populations not exhibiting those tales. Looking for smaller packages of tales or individual tales and their variants can be useful to shed light on the formation process of this vast body of popular knowledge. The long-range patterns detected by our analyses may complement this picture by suggesting a more ancient origin of some of these folktales (SI Appendix). On a broader level, these results can be used in the future to infer directional trends of cultural dispersal as well as to test for the emergence of systematic social biases [such as prestige bias, conformism/anticonformism, heterophily, and content-dependent biases] or cultural barriers different from linguistic ones, which have a chronology that may be independently ascertained.

If you are interested in studies about folktales, and especially those related to Indo-European traditions, you can check out the following articles I found interesting in the past:

Related:

Featured image (featured also in the article): Possible focal area and dispersion pattern for tale ATU313 “The Magic Flight,” one the most popular folktales in this dataset, which may have been additionally spread through population movement and replacement. It is interesting to note how this tale reached locations that are far from its putative origin (such as Japan and southeastern Africa), whereas it was not retained by many populations located in between (gray dots).

Something is very wrong with models based on the so-called ‘steppe admixture’ – and archaeologists are catching up

steppe-admixture

Russian archaeologist Leo Klejn has published an article Discussion: Are the Origins of Indo-European Languages Explained by the Migration of the Yamnaya Culture to the West?, which includes the criticism received from Wolfgang Haak, Iosif Lazaridis, Nick Patterson, and David Reich (mainly on the genetic aspect), and from Kristian Kristiansen, Karl-Göran Sjögren, Morten Allentoft, Martin Sikora, and Eske Willerslev (mainly on the archaeological aspect).

I will not post details of Klejn’s model of North-South Proto-Indo-European expansion – which is explained in the article, and relies on the north-south cline of ‘steppe admixture’ in the modern European population -, since it is based on marginal anthropological methods and theories, including glottochronological dates, and archaeological theories from the Russian school (mainly Zalyzniak), which are obviously not mainstream in the field of Indo-European Studies, and (paradoxically) on the modern distribution of ‘steppe admixture’…

The most interesting aspects of the article are the reactions to the criticism, some of which can be used from the point of view of the Indo-European demic diffusion model, too. It is sad, however, that they didn’t choose to answer earlier to Heyd’s criticism (or to Heyd’s model, which is essentially also that of Mallory and Anthony), instead of just waiting for proponents of the least interesting models to react…

The answer by Haak et al.:

Klejn mischaracterizes our paper as claiming that practitioners of the Corded Ware culture spoke a language ancestral to all European Indo-European languages, including Greek and Celtic. This is incorrect: we never claim that the ancestor of Greek is the language spoken by people of the Corded Ware culture. In fact, we explicitly state that the expansion of steppe ancestry might account for only a subset of Indo-European languages in Europe. Klejn asserts that ‘a source in the north’ is a better candidate for the new ancestry manifested in the Corded Ware than the Yamnaya. While it is indeed the case that the present-day people with the greatest affinity to the Corded Ware are distributed in north-eastern Europe, a major part of the new ancestry of the Corded Ware derives from a population most closely related to Armenians (Haak et al., 2015) and hunter-gatherers from the Caucasus (Jones et al., 2015). This ancestry has not been detected in any European huntergatherers analysed to date (Lazaridis et al., 2014; Skoglund et al., 2014; Haak et al., 2015; Fu et al., 2016), but made up some fifty per cent of the ancestry of the Yamnaya. The fact that the Corded Ware traced some of its ancestry to the southern Caucasus makes a source in the north less parsimonious.

In our study, we did not speculate about the date of Proto-Indo-European and the locations of its speakers, as these questions are unresolved by our data, although we do think the genetic data impose constraints on what occurred. We are enthusiastic about the potential of genetics to contribute to a resolution of this longstanding issue, but this is likely to require DNA from multiple, as yet unsampled, ancient populations.

Klejn response to that:

Allegedly, I had accused the authors of tracing all Indo-European languages back to Yamnaya, whereas they did not trace all of them but only a portion! Well, I shall not reproach the authors for their ambiguous language: it remains the case that (beginning with the title of the first article) their qualifications are lost and their readers have understood them as presenting the solution to the whole question of the origins of Indo-European languages.

(…) they had in view not the Proto-Indo-European before the separation of the Hittites, but the language that was left after the separation. Yet, this was still the language ancestral to all the remaining Indo-European languages, and the followers of Sturtevan and Kluckhorst call only this language Proto-Indo-European (while they call the initial one Indo-Hittite). The majority of linguists (specialists in Indo-European languages) is now inclined to this view. True, the breakup of this younger language is several hundred years more recent (nearly a thousand years later according to some glottochronologies) than the separation of Anatolian languages, but it is still around a thousand years earlier than the birth of cultures derived from Yamnaya.
More than that, I analysed in my criticism both possibilities — the case for all Indo-European languages spreading from Yamnaya and the case for only some of them spreading from Yamnaya. In the latter case, it is argued that only the languages of the steppes, the Aryan (Indo- Iranian) are descended from Yamnaya, not the languages of northern Europe. Together with many scholars, I am in agreement with the last possibility. But, then, what sense can the proposed migration of the Yamnaya culture to the Baltic region have? It would bring the Indo-Iranian proto-language to that region! Yet, there are no traces of this language on the coasts of the Baltic!

My main concern is that, to my mind, one should not directly apply conclusions from genetics to events in the development of language because there is no direct and inevitable dependence between events in the life of languages, culture, and physical structure (both anthropological and genetic). They can coincide, but often they all follow divergent paths. In each case the supposed coincidence should be proved separately.

The authors’ third objection concerns the increase of the genetic similarity of European population with that of the Yamnaya culture. This increases in the north of Europe and is weak in the south, in the places adjacent to the Yamnaya area, i.e. in Hungary. This gradient is clearly expressed in the modern population, but was present already in the Bronze Age, and hence cannot be explained by shifts that occurred in the Early Iron Age and in medieval times. However, the supposed migration of the Yamnaya culture to the west and north should imply a gradient in just the opposite direction!

Regarding the arguments of Kristiansen and colleagues:

[They argue that] in two early burials of the Corded Ware culture (one in Germany, the other in Poland) some single attributes of Yamnaya origin have been found.

(…) if this is the full extent of Yamnaya infiltration into central Europe—two burials (one for each country) from several thousands (and from several hundreds of early burials)—then it hardly amounts to large-scale migration.

Quite recently we have witnessed the success of a group of geneticists from Stanford University and elsewhere (Poznik et al., 2016). They succeeded in revealing varieties of Y-chromosome connected with demographic expansions in the Bronze Age. Such expansion can give rise to migration. Among the variants connected with this expansion is R1b, and this haplogroup is typical for the Yamnaya culture. But what bad luck! This haplogroup connected with expansion is indicated by the clade L11, while the Yamnaya burials are associated with a different clade, Z2103, that is not marked by expansion. It is now time to think about how else the remarkable results reached by both teams of experienced and bright geneticists may be interpreted.

Regarding the work of Heyd,

(…) with regard to the barrow burials of the third millennium BC in the basin of the Danube, although they have been assigned to the Yamnaya culture, I would consider them as also belonging to
another, separate culture, perhaps a mixed culture: its burial custom is typical of the Yamnaya, but its pottery is absolutely not Yamnaya, but local Balkan with imports of distinctive corded beakers (Schnurbecher). I would not be surprised if
Y-chromosome haplogroups of this population were somewhat similar to those of the Yamnaya, while mitochondrial groups were indigenous. As yet, geneticists deal with great blocks of populations and prefer to match them to very large and generalized cultural blocks, while archaeology now analyses more concrete and smaller cultures, each of which had its own fate.

Iosif Lazaridis shares more thoughts on the discussion in his Twitter account:

As we mentioned in Haak, Lazaridis et al. (2015), the Yamnaya are the best proximate source for the new ancestry that first appears with the Corded Ware in central Europe, as it has the right mix of both ANE (related to Native Americans, MA1, and EHG), but also Armenian/Caucasus/Iran-like southern component of ancestry. The Yamnaya is a westward expansive culture that bears exactly the two new ancestral components (EHG + Caucasus/Iran/Armenian-like).
As for the Y-chromosome, it was already noted in Haak, Lazaridis et al. (2015) that the Yamnaya from Samara had Y-chromosomes which belonged to R-M269 but did not belong to the clade common in Western Europe (p. 46 of supplement). Also, not a single R1a in Yamnaya unlike Corded Ware (R1a-dominated). But Yamnaya samples = elite burials from eastern part of the Yamnaya range. Both R1a/R1b found in Eneolithic Samara and EHG, so in conclusion Yamnaya expansion still the best proximate source for the post-3,000 BCE population change in central Europe. And since 2015 steppe expansion detected elsewhere (Cassidy et al. 16, Martiniano et al. 17, Mittnik et al. 17, Mathieson et al. 17, Lazaridis et al. 2016 (South Asia) and …?…

I love the smell of new wording in the morning… viz. Yamnaya best proximate source for Corded Ware, Corded Ware might account for only a subset of Indo-European languages, Corded Ware representing Aryan languages (probably Klejn misinterprets what the authors mean, i.e. some kind of Indo-Slavonic or Germano-Balto-Slavic group)…

We shall expect more and more ambiguous rewording and more adjustments of previous conclusions as new papers and new criticisms appear.

Related:

Featured image from the article: Distribution of the ‘Yamnaya’ genetic component in the populations of Europe (data taken from Haak et al., 2015). The intensity of the colour corresponds to the contribution of this component in various modern populations

Indo-European and Central Asian admixture in Indian population, dependent on ethnolinguistic and geodemographic divisions

indian-population-genetics

Preprint paper at BioRxiv, Dissecting Population Substructure in India via Correlation Optimization of Genetics and Geodemographics, by Bose et al. (2017), a mixed group from Purdue University and IBM TJ Watson Research Center. A rather simple paper, which is nevertheless interesting in its approach to the known multiple Indian demographic divisions, and in its short reported methods and results.

Abstract:

India represents an intricate tapestry of population substructure shaped by geography, language, culture and social stratification operating in concert. To date, no study has attempted to model and evaluate how these evolutionary forces have interacted to shape the patterns of genetic diversity within India. Geography has been shown to closely correlate with genetic structure in other parts of the world. However, the strict endogamy imposed by the Indian caste system, and the large number of spoken languages add further levels of complexity. We merged all publicly available data from the Indian subcontinent into a data set of 835 individuals across 48,373 SNPs from 84 well-defined groups. Bringing together geography, sociolinguistics and genetics, we developed COGG (Correlation Optimization of Genetics and Geodemographics) in order to build a model that optimally explains the observed population genetic sub-structure. We find that shared language rather than geography or social structure has been the most powerful force in creating paths of gene flow within India. Further investigating the origins of Indian substructure, we create population genetic networks across Eurasia. We observe two major corridors towards mainland India; one through the Northwestern and another through the Northeastern frontier with the Uygur population acting as a bridge across the two routes. Importantly, network, ADMIXTURE analysis and f3 statistics support a far northern path connecting Europe to Siberia and gene flow from Siberia and Mongolia towards Central Asia and India.

Among the most interesting results (emphasis mine):

Our meta-analysis of the ADMIXTURE output shows that the IE and DR populations across castes shared very high ancestry, indicating the autochthonous origin of the caste system in India (Figure 2). f3 statistics show that most of the castes and tribes in India are admixed, with contributions from other castes and/or tribes, across languages affiliations (Supplementary Table 4 and Supplementary Note). The geographically isolated Tibeto-Burman tribes and the Dravidian speaking tribes appear to be the most isolated in India. Linear Discriminant Analysis on the normalized data set clearly supports genetic strati cation by castes and languages in the Indian sub-continent

(…)

Our meta-analysis of the ADMIXTURE plot in Figure 4A quantifies the ADMIXTURE results (darker colors indicate higher pairwise shared ancestry). Indian populations show a greater proportion of shared ancestry with the so-called Indian Northwestern Frontier populations, namely the tribal populations spanning Afghanistan and Pakistan. Central Asian populations share higher degrees of ancestry with IE and DR Froward castes. Uygurs share high degrees of ancestry with Indian populations.

(…)

f3 statistics (all negative Z-scores are shown) indicate Chinese and Siberian ancestry contributing to the Tibeto-Burman tribal speakers. On the other hand, the Mongols and the Europeans have contributed significant amounts of ancestry to the Indo-European and Tibeto-Burman forward castes. F3 statistics also show that the Central Asians are an admixed population with signs of admixture from Caucasus and other parts of Europe.

Among the results for proportions of shared ancestry between Indians and Eurasians (FIG. 4), there is an obvious influence of European admixture (Caucasus, and Southern, Central, and Northern EU), potentially from the Yamna-Corded Ware expansion, in IE_ForwardCaste, which is lessened in IE_BackwardCaste and also in IE_Tribal, while DR_ForwardCaste shows again more admixture than IE_Tribal, but diminishing with lower castes and quite low in DR_Tribal.

Ancestry from Central Asia is strong with a similar pattern, which hints at the influence of Sintashta, Andronovo, and BMAC influence in the expansion of the Steppe component, even more than a later Turkic component.

On the other hand, the influence from Turkey is difficult to assess, given the complex genetic history of Anatolia, but the map contained in Fig. 6 doesn’t feel right, not only from a genetic viewpoint, but also from linguistic and archaeological points of view. This is the typical map created with admixture analyses that is wrong because of not taking into account anthropological theories.

Quite interesting is then the influence of admixture in these different ethnolinguistic groups, Indo-European and Dravidic, which points to an initially greater expansion of Indo-European speakers, and later resurge of Dravidian languages.

Featured image contains simplified origin and data of samples studied, from the article.

Related:

Prometheus Engineer language in updated alternative version of A Grammar of Modern Indo-European

As we announced yesterday at Dnghu, our book A Grammar of Modern Indo-European, Third Edition has been revised, and the new version of the Proto-Indo-European lexicon has been added and it is available now online and printed at Amazon, without the Etymology section – it is therefore a cheaper, more handy manual.

But, more importantly, we have added a new section and published a parallel Prometheus Edition – Engineer language of the grammar, that includes unprecedented content with discussion of Prometheus’ recreated Late Proto-Indo-European dialect of the Prometheus/Alien/Predator fiction universe. There is also a printed version at Amazon. As you probably know already, our grammar is a Late Indo-European dialectal grammar, so it wasn’t difficult to add some information on ‘Engineer’ for fans.

We have opened a blog dedicated to the language, and a new dedicated section in our forum for discussion on this recreated language, and on the universe shared by Alien, Predator, Alien vs. Predator, and now also Prometheus franchises.

In my opinion, given the dialectal nature of the language as we know it now, the richness of the reconstruction on which it is based, and the specialized group that Ridley Scott contacted to work on it, it could be the most interesting conlang ever – or reclang, since it is recreated from a reconstruction…