The renewed ‘Kurgan model’ of Kristian Kristiansen and the Danish school: “The Indo-European Corded Ware Theory”

Allentoft Corded Ware

A popular science article on Indo-European migrations has appeared at Science News, entitled How Asian nomadic herders built new Bronze Age cultures, signed by Bruce Bower. While the article is well-balanced and introduces new readers to the current status quo, and the confrontation between theories led by Kristiansen/Anthony vs. Heyd, it reverberates yet again the conclusions of the 2015 Nature articles on the subject, especially by its featured image.

As I have argued many times why the recent ‘Yamnaya -> Corded Ware -> Bell Beaker’ migration model is wrong, mainly within my essay Indo-European demic diffusion model, but also in articles of this blog, most recently in the post Correlation does not mean causation: the damage of the ‘Yamnaya ancestral component’, and the ‘Future America’ hypothesis). It is known that Nature is a bit of ‘tabloid’ in the publishing industry, and these 2015 articles offered simplistic conclusions based on a wrong assessment of archaeological and linguistic data, in search for groundbreaking conclusions.

An excerpt from Bower’s article:

Corded Ware culture emerged as a hybrid way of life that included crop cultivation, breeding of farm animals and some hunting and gathering, Kristiansen argues. Communal living structures and group graves of earlier European farmers were replaced by smaller structures suitable for families and single graves covered by earthen mounds. Yamnaya families had lived out of their wagons even before trekking to Europe. A shared emphasis on family life and burying the dead individually indicates that members of the Yamnaya and Corded Ware cultures kept possessions among close relatives, in Kristiansen’s view.

“The Yamnaya and the Corded Ware culture were unified by a new idea of transmitting property between related individuals and families,” Kristiansen says.

Yamnaya migrants must have spoken a fledgling version of Indo-European languages that later spread across Europe and parts of Asia, Kristiansen’s group contends. Anthony, a longtime Kristiansen collaborator, agrees. Reconstructed vocabularies for people of the Corded Ware culture include words related to wagons, wheels and horse breeding that could have come only from the Yamnaya, Anthony says.

I have already talked about Kristiansen’s continuation of Gimbutas’ outdated ideas: we are seeing a renewed effort by some Scandinavian (mainly Danish) scholars to boost (and somehow capitalise) the revitalised concept of the “Kurgan people”, although now the fundamental issue has been more clearly shifted to the language spoken by Corded Ware migrants.

As far as I can tell, this renewed interest began two years ago, with the simultaneous publication of genetic studies by Haak et al. (2015), and Allentoft et al. (2015), and the misuse of the cursed concept of ‘Yamnaya ancestry‘ to derive far-fetched conclusions.

On the other hand, genetic research is not solely responsible for this: David Anthony – who was apparently consulted by Haak et al. (2015) for their paper, where he appears as co-author – has kept a low (or lower) profile, and only recently has he merely suggested potential links between Corded Ware and Bell Beaker cultures in Lesser Poland, that might explain what (some geneticists have told him) appeared as a potential Yamna -> Corded Ware -> Bell Beaker migration in the first ancient samples studied.

Anthony’s migration model remains otherwise strongly based on Archaeology, offering a careful interpretation of potential contacts and migrations in the Pontic-Caspian steppe, and only marginally offers some views on Linguistics (based on Ringe’s controversial ‘glottochronological model’ of 2006), to the extent that he is compelled to explain the potential adoption of Indo-European by Corded Ware culture (CWC) peoples as multiple cultural diffusion events, since no migration is observed from the steppe to CWC territories.

I think he is thus showing a great deal of restraint, not jumping on the bandwagon of this recent trend based on scarce genetic finds – and therefore losing also the opportunity to publish articles in journals of high impact factor….

This newly created Danish school, on the other hand, seems to be swimming with the tide. Kristiansen, known for his controversial ‘universal’ interpretations of European Prehistory – which are nevertheless more readable and interesting than most specialised literature on Archaeology, at least for us non-archaeologists – , has apparently seized the opportunity to give a strong impulse to his theories.

Not that there is nothing wrong with that, of course, but sometimes it might seem that a lot of papers (or even researchers) support something, when in fact there are only a few of them, working closely together

I see therefore three main “branches” of this support (two of them, Genetics and Linguistics, only recently giving some limited air to this dying hypothesis), with a closely related group of people involved in this model, and they are lending continuous support to each other, by repeating the same theory – and repeating the same misleading map images (like the one shown in the article) – , so that the circular reasoning they represent is concealed behind seemingly independent works.

The theory and its development

The main theory seems to be rooted then in Kristiansen’s hypothesis, whose first article on the subject seems to be Prehistoric Migrations – the Case of the Single Grave and Corded Ware Cultures (1989), supporting the Kurgan model applied to the Corded Ware migrations. It was probably a kind of a breakthrough in Archaeology, bringing migration to mainstream Archaeology again (followed closely by Anthony), and he deserves merit for this.

After this proposal, there are mostly just his publications supporting this model. Nevertheless, Kristiansen’s model, I gather, did not involve the sudden Yamnaya -> Corded Ware migrations discussed in recent genetic articles, but long-lasting contacts between peoples and cultures from the North Pontic steppe, Trypillian, and Globular Amphora, that formed a new mixed one, the Corded Ware people and culture. Also, in Gimbutas’ original model of migration (1963), waves of Kurgan migrants are also described into Vučedol and Bell Beaker, which have been apparently forgotten in recent models*.
* The most recent model by Anthony cannot even recognize migration waves from Yamna into the Corded Ware culture, and describes potential routes (or modes) of cultural diffusion.

kristiansen-corded-ware-kurgan
Proposal for the origin and spread of the Corded Ware/ Battle Axe cultural complex: 1) Distribution of CWC groups; 2) Yamna culture; 3) presumed area of origin; 4) presumed main directions of the primary distribution. Also numbered are other individual CW cultures. From Kristiansen (1989).

Then – skipping the years of simplistic phylogeography based on modern haplogroup distribution – we have to jump directly to Allentoft (of the Natural History Museum of Denmark) and cols. and their article on population genomics of Bronze Age Eurasia (2015), with which Kristiansen collaborated, and which offers the first direct association of Corded Ware as the vector of expansion of Indo-European peoples and languages from Yamna. An interesting take on the Yamna -> Corded Ware -> Bell Beaker question is represented by their very ‘kurgan-like’ Corded Ware-centric map:

allentoft-yamna-corded-ware
Detail of Fig. 1 from Allentoft et al. (2015): “Distribution of Early Bronze Age cultures Yamnaya, Corded Ware, and Afanasievo with arrows showing the Yamnaya expansions”.

And suddenly, we are now seeing more works that support the central thesis of the group – that Corded Ware must have brought Indo-European languages to Europe:

Recent publications by K-G Sjögren – from the same department as Kristiansen, at the University of Gothenburg – seem to imply that there was a direct connection Corded Ware -> Bell Beaker in central Europe.

Guus Kroonen‘s recent hypothesis of a potential (Proto-Semitic-like) Germanic substrate (2012) has been added recently to the cause, in supporting with Iversen (also from the University of Copenhaguen) a link with the Battle Axe/Funnelbeaker culture interaction. However, in the archaeological-linguistic model it seems that Germanic must predominate over the rest of Indo-European languages in terms of age, representing the first wave of Indo-Europeanization in Europe (wat?!), whereas Balto-Slavic is much younger and unrelated…? But didn’t they share the same substrate (as did partially Greek) in Kroonen (2012)? I think Kroonen’s hypothesis might be better explained through an earlier contact in the North Pontic steppe

kroonen-iversen
Modified from Kristiansen et al. (2017). “Schematic representation of how different Indo-European branches have absorbed words (circles) from a lost Neolithic language or language group (dark fill) in the reconstructed European linguistic setting of the third millennium BC, possibly involving one or more hunter gatherer languages (light fill) (after Kroonen & Iversen 2017)”.

Wrap-up

This recently created Danish pressure group is not something bad per se. I don’t agree with their hypothesis (or rather evolving hypotheses, since they change with new genetic results and linguistic proposals, as is shown in Kristiansen et al. 2017), but I understand that the group continues a recent tradition:

Publications are always great to advance in knowledge, and if they bring some deal of publicity, and more publications (with the always craved impact factor), and maybe more investment in the departments (with more local jobs and prestige)… why not?

However, this model of workgroup system of research is reminiscent of the Anatolian homeland group loosely created around Renfrew; the Palaeolithic Continuity workgroup around Cavalli-Sforza; or (more recently) the Celtic from the West group around Cunliffe and Koch. The difference between Kristiansen’s workgroup and supporters of all those other models, in my opinion, is that (at least for the moment) their collaboration is not obvious to many.

Therefore, to be fair with any outsider, I think this group should clearly state their end model: I propose the general term “Indo-European Corded Ware Theory” (IECWT) workgroup, because ‘Danish’ is too narrow, and ‘Scandinavian’ too broad to represent the whole group. But any name will do.

My opinion on the IECWT

As you can see, no single strong proof exists in support of the IECWT:

  • Not for a solid model of PIE expansion from Corded Ware, not even within the IECWT group, where there is no support (to date) for a Balto-Slavic expansion associated with the Corded Ware culture… Or any other dialect, for that matter;
  • Not for a Corded Ware -> Bell Beaker connection – that is, before the publication of Allentoft et al. (2015) and articles reverberating their conclusions;
  • Not for a unified Pre-Germanic community before the Dagger Period, and still less linked with the expansion of the Corded Ware culture from the steppe – that connection is found only in Anthony (2007), where he links it with Usatovo, which seems to late with the current data.

The wrong interpretation of scarce initial ancient samples has been another feeble stone put over the ruins of Gimbutas’ theory. While her simple theory of Kurgan invaders was certainly a breakthrough in her time – when speaking about migrating Indo-European peoples was taboo -, it has since been overcome by more detailed accounts of what happened in east and central Europe during Prehistory.

However, a lot of people are willing to consume post-truth genetic-based citebait like crazy, in a time when Twitter, Facebook, blogs, etc. seem to shape the general knowledge, while dozens of new, carefully prepared papers on Archaeology and Linguistics related to Indo-European peoples get published weekly and don’t attract any attention, just because they do not support these simplistic claims, or precisely because they fully reject them.

One is left to wonder if the support of Corded Ware + R1a representing Pre-Germanic is also in line with the most natural human Kosinnian trends, whereby the older your paternal line and your ancestral language are connected to your historical territory, the better. An older connection of Germanic to Northern Scandinavia – and thus an ancestral cultural diffusion from north to south – seems to better fit the traditional idea of an autochthonous Germanic homeland in Scandinavia, instead of a bunch of southern Bell Beaker invaders bringing the language that could only develop as a common Nordic language during the Bronze Age in a genetically-diverse community…

Just as we are seeing some Slavic people keen to recreate a ‘Northern group’ with Germanic in a Germano-Balto-Slavic Corded Ware culture, and a renewed interest in skin, hair and eye colour by amateur geneticists, it is only natural to expect similar trends in certain sectors of the Germanic-speaking community.

NOTE: I feel a bit like an anti-IECWT hooligan here. Judging by the reactions to criticism of the Out of India Theory, this post is likely to cause some people to feel bad.

It is not intended to be against these researchers individually, though. All of them have certainly contributed in great ways to their fields, indeed more than I have to any field: Kristiansen is well-known for his careful, global interpretations of European prehistory (and has been supporting his model for quite a long time). I do like Kroonen’s ideas of a Pre-Germanic substratum. And people involved in the group do so probably because they collaborate closely with each other, and because of the huge pressure to publish in journals of high impact factor, so to mix their disparate research within a common model seems only natural.

But their collaboration is boosting certain wrong ideas, and is giving way to certain misconceptions in Linguistics, and also sadly renewed past ethnocentric views of language in Northern Europe – that will be luckily demonstrated, again, wrong. After all, publications (like ideas in general) are subjected to criticism, as mine are. Researchers who publish know their work is subjected to criticism, and not only before publication, but also – and probably more so – after it. That a paper can be incorrect, biased, or even completely absurd, does not mean the person who wrote it is a fool. That’s the difference between criticising ideas and insulting. If criticism offends you, you shouldn’t be publishing. Period.

Related:

Featured image: From Allentoft et al. (2015)“>Allentoft et al. (2015). See here for full caption.

mtDNA haplogroup frequency analysis from Verteba Cave supports a strong cultural frontier between farmers and hunter-gatherers in the North Pontic steppe

eneolithic-forest-zone

New preprint paper at BioRxiv, led by a Japanese researcher, with analysis of mtDNA of Trypillians from Verteba Cave, Analysis of ancient human mitochondrial DNA from Verteba Cave, Ukraine: insights into the origins and expansions of the Late Neolithic-Chalcolithic Cututeni-Tripolye Culture, by Wakabayashi et al. (2017).

Abstract:

Background: The Eneolithic (~5,500 yrBP) site of Verteba Cave in Western Ukraine contains the largest collection of human skeletal remains associated with the archaeological Cucuteni-Tripolye Culture. Their subsistence economy is based largely on agro-pastoralism and had some of the largest and most dense settlement sites during the Middle Neolithic in all of Europe. To help understand the evolutionary history of the Tripolye people, we performed mtDNA analyses on ancient human remains excavated from several chambers within the cave.

Results: Burials at Verteba Cave are largely commingled and secondary in nature. A total of 68 individual bone specimens were analyzed. Most of these specimens were found in association with well-defined Tripolye artifacts. We determined 28 mtDNA D-Loop (368 bp) sequences and defined 8 sequence types, belonging to haplogroups H, HV, W, K, and T. These results do not suggest continuity with local pre-Eneolithic peoples, but rather complete population replacement. We constructed maximum parsimonious networks from the data and generated population genetic statistics. Nucleotide diversity (π) is low among all sequence types and our network analysis indicates highly similar mtDNA sequence types for samples in chamber G3. Using different sample sizes due to the uncertainly in number of individuals (11, 28, or 15), we found Tajima’s D statistic to vary. When all sequence types are included (11 or 28), we do not find a trend for demographic expansion (negative but not significantly different from zero); however, when only samples from Site 7 (peak occupation) are included, we find a significantly negative value, indicative of demographic expansion.

Conclusions: Our results suggest individuals buried at Verteba Cave had overall low mtDNA diversity, most likely due to increased conflict among sedentary farmers and nomadic pastoralists to the East and North. Early Farmers tend to show demographic expansion. We find different signatures of demographic expansion for the Tripolye people that may be caused by existing population structure or the spatiotemporal nature of ancient data. Regardless, peoples of the Tripolye Culture are more closely related to early European farmers and lack genetic continuity with Mesolithic hunter-gatherers or pre-Eneolithic groups in Ukraine.

Genetic finds keep supporting the long-lasting cultural and linguistic frontier that Anthony (2007) – among others – asserted existed in the North-West Pontic steppe in the Mesolithic and Neolithic, between western steppe cultures and farmers, while it disproves Kristiansen’s theories of Sredni Stog expansion in Kurgan waves with a mixture of GAC and Trypillia within the Corded Ware culture:

Previous ancient DNA studies showed that hunter-gatherers before 6,500 yrBP in Europe commonly had haplogroups U, U4, U5, and H, whereas hunter-gatherers after 6,500 yrBP in Europe had less frequency of haplogroup H than before. Haplogroups T and K appeared in hunter-gatherers only after 6,500 yrBP, indicating a degree of admixture in some places between farmers and hunter-gatherers. Farmers before and after 6,500 yrBP in Europe had haplogroups W, HV*, H, T, K, and these are also found in individuals buried at Verteba Cave. Therefore, our data point to a common ancestry with early European farmers. Our data also suggest population replacement. Mathieson et al. analyzed a number of Neolithic Ukrainian samples (petrous bone) from several sites in southern, northern, and western Ukraine, dating to ~8,500 – 6,000 yrBP, and found exclusively U (U4 and U5) mtDNA lineages. It should be noted that ‘Neolithic’ in this context does not mean the adoption of agriculture, but rather simply coinciding with a change in material culture. They also analyzed several Trypillian individuals from Verteba Cave (different samples from the those included in this study). Similar to our findings, they found a wider diversity of mtDNA lineages, including H, HV, and T2b. These data, combined with our results, appear to confirm almost complete population replacement by individuals associated with the Tripolye Culture during the Middle to Late Neolithic.

The findings also hint to potential contacts of Yamna with Usatovo as predicted by Anthony (2007), or alternatively (lacking precise dates) to contacts with Corded Ware migrants:

Trypillians were very much a distinct people who most likely displaced 1 local hunter-gatherers with little admixture. Haplogroup W was also observed in several specimens deriving from Site G3. Although we are unsure if all of these haplogroups come from a single or multiple individuals, this observation is interesting in that it is relatively rare and isolated among Neolithic samples. It has, however, been found in samples dating to the Bronze Age. In the study by Wilde et al. [35], they found haplogroup W present in two samples from the Early Bronze Age associated with the Yamnaya and Usatovo cultures. The Usatovo culture (~ 3500 – 2500 BC) was found in Romania, Moldova, and southern Ukraine. It was the conglomeration of Tripolye and North Pontic steppe cultures. Therefore, this individual could link the Trypillian peoples to the Usatovo peoples and perhaps to the greater Yamnaya steppe migrations during the Bronze Age that lead to the Corded Ware Culture.

On the other hand, an article written in terms of mtDNA haplogroup frequencies seems to offer too little proof of anything today. The lack of Y-DNA haplogroups and data on admixture makes their interpretations provisional, subject to change when these further data are published. Also, radiocarbon dating is only confident for individuals of one site (site 7), dated ca. 5,500 cal BP, while “other chambers in the cave are not as confidently dated”…

verteba-cave-mtDNA
“Based on the 8 sequence types of the mtDNA D-loop, a maximum parsimonious phylogenetic network was constructed. Circles represent the sequence types, and the size of the circle is proportional to the number of samples. Numbers on the branches between the circles are nucleotide position numbers (+16,000) of the human mitochondrial genome sequence (rCRS). Information about the location (chamber within the cave) where the specimen was excavated is also provided. Areas 2 and 17 are part of Site 7, and these are defined as a separate chamber, although they are located in close proximity within Site 7. The other chambers, Site 20, G2, and G3, are independent and separate locations within the cave. ‘Undefined’ chamber describes an unknown location within the cave. Specimens from each chamber showed deviation for the sequence type distribution observed in the sample set. For example, specimens excavated from Site 7 had five unique sequence types, (I, II, III, IV, and VIII), while specimens excavated from chamber G 21 had mainly one sequence type (V)”. Made available by the authors under a CC-BY-NC-ND 4.0 International license.

We had also seen signs of conflict between Trypillian and steppe cultures in a recent article, Violence at Verteba Cave, Ukraine: New Insights into the Late Neolithic Intergroup Conflict, by Madden et al. (2017):

Many researchers have pointed to the huge “megasites” and construction of fortifications as evidence of intergroup hostilities among the Late Neolithic Tripolye archaeological culture. However, to date, very few skeletal remains have been analyzed for the types of traumatic injury that serve as direct evidence for violent conflict. In this study, we examine trauma on human remains from the Tripolye site of Verteba Cave in western Ukraine. The remains of 36 individuals, including 25 crania, were buried in the gypsum cave as secondary interments. The frequency of cranial trauma is 30-44% among the 25 crania, six males, four females and one adult of indeterminate sex displayed cranial trauma. Of the 18 total fractures, 10 were significantly large and penetrating suggesting lethal force. Over half of the trauma is located on the posterior aspect of the crania, suggesting the victims were attacked from behind. Sixteen of the fractures observed were perimortem and two were antemortem. The distribution and characteristics of the fractures suggest that some of the Tripolye individuals buried at Verteba Cave were victims of a lethal surprise attack. Resources were limited due to population growth and migration, leading to conflict over resource access. It is hypothesized that during this time of change burial in this cave aided in development of identity and ownership of the local territory.

Related:

Correlation does not mean causation: the damage of the ‘Yamnaya ancestral component’, and the ‘Future American’ hypothesis

New Ukraine Eneolithic sample from late Sredni Stog, near homeland of the Corded Ware culture

The concept of “outlier” in studies of Human Ancestry, and the Corded Ware outlier from Esperstedt

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

Before steppe ancestry: Europe’s genetic diversity shaped mainly by local processes, with varied sources and proportions of hunter-gatherer ancestry

neolithic-mesolithic-europe

The definitive publication of a BioRxiv preprint article, in Nature: Parallel palaeogenomic transects reveal complex genetic history of early European farmers, by Lipson et al. (2017).

The dataset with all new samples is available at the Reich Lab’s website. You can try my drafts on how to do your own PCA and ADMIXTURE analysis with some of their new datasets.

Abstract:

Ancient DNA studies have established that Neolithic European populations were descended from Anatolian migrants who received a limited amount of admixture from resident hunter-gatherers. Many open questions remain, however, about the spatial and temporal dynamics of population interactions and admixture during the Neolithic period. Here we investigate the population dynamics of Neolithization across Europe using a high-resolution genome-wide ancient DNA dataset with a total of 180 samples, of which 130 are newly reported here, from the Neolithic and Chalcolithic periods of Hungary (6000–2900 BC, n = 100), Germany (5500–3000 BC, n = 42) and Spain (5500–2200 BC, n = 38). We find that genetic diversity was shaped predominantly by local processes, with varied sources and proportions of hunter-gatherer ancestry among the three regions and through time. Admixture between groups with different ancestry profiles was pervasive and resulted in observable population transformation across almost all cultural transitions. Our results shed new light on the ways in which gene flow reshaped European populations throughout the Neolithic period and demonstrate the potential of time-series-based sampling and modelling approaches to elucidate multiple dimensions of historical population interactions.

There were some interesting finds on a regional level, with some late survival of hunter-gatherer ancestry (and Y-DNA haplogroups) in certain specific sites, but nothing especially surprising. This survival of HG ancestry and lineages in Iberia and other regions may be used to revive (yet again) the controversy over the origin of non-Indo-European languages of Europe attested in historical times, such as the only (non-Uralic) one surviving to this day, the Basque language.

This study kept confirming the absence of Y-DNA R1b-M269 subclades in Central Europe before the arrival of Yamna migrants, though, which offers strong reasons to reject the Indo-European from the west hypothesis.

Here are first the PCA of samples included in this paper, and then the PCA of ancient Eurasians (Mathieson et al. 2017) and modern populations (Lazaridis et al. 2014) for comparison of similar clusters:

mesolithic-neolithic-PCA
First two principal components from the PCA. We computed the principal components (PCs) for a set of 782 present-day western Eurasian individuals genotyped on the Affymetrix Human Origins array (background grey points) and then projected ancient individuals onto these axes. A close-up omitting the present-day Bedouin population is shown. From Lipton et al. (2017(
pca-south-east-europe
PCA of South-East European and other European samples from Mathieson et al. (2017)
pca-ancient-modern-europe
Ancient and modern samples on Lazaridis et al. (2014)

Related:

Correlation does not mean causation: the damage of the ‘Yamnaya ancestral component’, and the ‘Future American’ hypothesis

america-languages-lowlandic

Human ancestry can only help solve anthropological questions by using all anthropological disciplines involved. I have said that many times in this blog.

Correlation does not mean causation

Really, it does not.

You might think the tenet ‘correlation does not mean causation‘ must be evident at this point in Statistics, and it must also be for all those using statistical methods in their research. But it is sadly not so. A lot of researchers just look for correlation, and derive conclusions – without even an initial sound hypothesis to be contrasted… You can judge for yourself, e.g. reading the many instances of this complaint in recent publications of Biomedical and Social Sciences, on the interesting blog Statistical Modeling, Causal Inference, and Social Science.

In anthropological questions regarding Indo-European studies there is an added handicap: not taking correlation to mean causation does also mean – to avoid at least the most obvious confounders – taking into account the multiple linguistic and archaeological data that are available right now, to explain the expansion of Indo-European languages.

You might also believe that international researchers in Human Evolutionary Biology – after all, this is essentially a biomedical discipline – are acquainted with statistical methods and their problems when applied to their field. And that scientific journals – and especially those with the highest impact factors, like Nature, Science, or PNAS – have professional, careful reviewers who would never accept papers that equal correlation with causation, especially when Social Sciences are involved (because this alone might make errors grow exponentially…). Sadly, this is obviously not so, either.

https://imgs.xkcd.com/comics/correlation.png

The ‘Yamnaya component’ concept and its damage

From Allentoft et al. (2015), emphasis is mine:

Both studies [Haak et al. (2015) and this one] found a genetic affinity between samples from a central European culture known as Corded Ware, which existed from around 2500 bc, and samples from the earlier Yamnaya steppe culture. This similarity between distant populations is best explained by a substantial westward expansion of the Yamnaya or their close relatives into central Europe (Fig. 1b). Such an expansion is consistent with the steppe hypothesis, which argues that Corded Ware cultures were a conduit for the dispersal of Indo-European languages into Europe.

More interesting than these vague words – and the short, almost invisible suggestion that Yamna may not be exactly the population behind Corded Ware peoples – are the maps that illustrated in Nature their risky hypothesis: they called it “steppe hypothesis“, like that (in general terms), as if everyone defending a steppe origin for Proto-Indo-European would support such a model, when they actually referred to the specific hypothesis of one of their authors (Kristiansen), one of the few archaeologists who keep Gimbutas’ concept of the ‘Kurgan peoples’ alive, based on the Corded Ware culture:

Allentoft Corded Ware
Allentoft et al. (2015): “They conclude that the Corded Ware culture of central Europe had ancestry from the Yamnaya. Allentoft et al. also show that the Afanasievo culture to the east is related to the Yamnaya, and that the Sintashta and Andronovo cultures had ancestry from the Corded Ware. Arrows indicate migrations — those from the Corded Ware reflect the evidence that people of this archaeological culture (or their relatives) were responsible for the spreading of Indo-European languages. All coloured boundaries are approximate.”

In many publications that followed, the trend has been to reproduce this graphical model, by asserting (or implying) that Bell Beaker peoples were the result of subsequent Corded Ware migrations, and indeed that Corded Ware peoples migrated from the Yamna culture, and were thus the vector of expansion for Indo-European languages in Europe.

All of this is being proven wrong, as I predicted: see Mathieson et al. (2017) and Olalde et al. (2017) for recently studied samples with ‘steppe component’, older than (and unrelated to) the Yamna culture. However, no retraction (or correction, whatever) has been published to date about the concept of the ‘Yamnaya ancestry expansion’, and its consequences.

We shall see then just a rather surreptitious shift in terminology from ‘Yamnaya’ to ‘steppe’ component, to adapt to the new data – i.e. some damage control while the ship of ‘Yamnaya ancestry’ capsizes – but little else. “Earlier ‘Yamnaya ancestry’, you say? Just, you know, let’s call it ‘steppe ancestry’ and shift the expansion of Indo-European languages to one or two thousand years earlier, and done!”

The damage of this post-truth genetics is already done: we will see the unending distribution on the Internet in general, and on social networks in particular, of these grandiose conclusions, of far-fetched Indo-European migration models that include the Corded Ware culture, of simplistic maps with apparently harmless ‘arrows of migration’ (like the above) representing fictional population movements suggesting nonexistent dialectal branches.

You might be one of those sceptics wary of so many boring statistical rules: “But it’s a safe reasoning: Yamanaya samples have an ‘ancestral component’ that is found elevated in Corded Ware samples, and less so in Bell Beaker samples, and PCA showed a similar result…so the migration model Yamnaya -> Corded Ware -> Bell Beaker is a priori correct, right?”

The ‘Future American’ hypothesis

Let me illustrate this attractive “Correlation = Causation” argument, using it to solve the problem of Future American languages.

Suppose we live in a future post-apocalyptic world ca. 3500 AD, with no surviving historical records before 3000 AD. None. Just investigation of cultures and their relationship by Archaeology, proto-languages reconstructed and language families identified by Linguistics, etc.

We have thus Future Germanic and Future Romance as the only language families spoken in Future Western Europe and in the Future Americas, in a distribution similar to the present day*, and we have certain somehow related archaeologically-defined cultures on both sides of the Atlantic, like Briton, Iberian, Norman, or Lowlandish, although their distribution remains partly undefined in time and space.

* If you are really curious about this scenario, you can read about the potential evolution of a Future North-American language.

But what languages did the ancestors of Future Americans speak, and who spread them? That question remains far from being settled by our future researchers, in spite of the solidest linguistic and migration models (talking mainly about Briton and Iberian cultures): too many authorities out there questioning them, fighting to impose their own pet theories.

Suddenly, the newly developed field of Human Ancestry comes to save the day. So let’s say we have this map of ancient samples recovered (dated from, say, the 6th to the 18th century AD), and our study is centered on the newly described “Western European” component (a precise combination of, say, WHG+steppe), which peaks in early samples from the Low Lands – hence we call it, quite daringly, “Lowlandic component“.

Our group is keen to demonstrate that the ancient Lowlandic culture described in Archaeology (marked especially by the worldwide distribution of tulips among other traits) is the origin of Western European and American languages… Now, let’s reach conclusions about migrations in the Middle Ages!

america-languages-lowlandic
‘Future American’ hypothesis. Migration routes in Western Europe and the Americas during the Middle Ages, based on the ‘Lowlandic component’ (Click to open higher quality version).

PCA shows that South-West European samples cluster closely to some North-West European samples, and that some late South American samples available cluster at some distance from North American samples – nearer to a native component represented by two individuals with 0% Lowlandic ancestry and a different cluster in PCA. And some North-American samples cluster quite closely to North-West European samples.

Based on the decrease in ‘Lowlandic component’ in the different samples and on PCA, we conclude that Lowlandic peoples (“or their close relatives”) must have migrated at the same time to North America, South America (or potentially from North America to South America?) as well as western, central, and northern Europe. Both migration events must have happened roughly at the same time, in part because both distinct language families appear in a north-south distribution, and Proto-Lowlandic must be (according to Genetics) the ancestor of both, Proto-Future-Germanic and Proto-Future-Romance.

That makes a lot of sense! A huge Lowlandic pressure for migration, you see. Push-pull mechanisms and stuff. A Lowlandic Empire probably (scattered remains are found everywhere)! And, judging by the presence of the ‘Lowlandic component’ in Future East Europe from the Elbe to the Vistula, maybe Lowlandic peoples spread Proto-Slavic, too! We can even date the common Lowlandic-Slavic proto-language this way! So many groundbreaking conclusions!

Future scholars supporting the Lowlandic homeland are on fire; they can’t get enough of publishing papers on the subject. “Two different Future American language families with cultural origins in Britain and Iberia, my ass! Because genetics.”

And don’t forget the future people of haplogroup R1b-U106 and high Lowlandic component: Wow, they are the heirs of those who expanded Future Germanic and Future Romance languages everywhere, aren’t they? How proud they must be. And who wouldn’t want to have these tall, blond, blue-eyed Lowlanders as their forefathers? Personalised genetic analysis is selling like crazy: “let’s know our Lowlandic percentage!”. Everyone is happy, colourful maps with lots of arrows and shit…

But – your future you might ask in awe, seeing that this doesn’t sound quite right, based on your basic archaeological and linguistic knowledge:

  • What about specific models of migration proposed to date? The solidest ones, not just anyone that seems to fit?
  • What about the dialectal classification of languages? The mainstream ones, not those that are compatible with this interpretation?
  • What about archaeological cultures to which individual samples belonged?
  • What about the actual dates of each sample? And how this date relates to the state of the culture to which it belongs?
  • What about the haplogroups, and the actual subclade of each haplogroup?
  • What about the territories, cultures, and dates not sampled, could they change this interpretation in light of known archaeological models?
  • And what about the actual origin of that ancestral component they so frivolously named? Dit it really appear ex nihilo in the Low Lands, and expanded from it?

“Who cares! This new data is sooo coool… And it proves what we wanted, what a coincidence! And it’s numbers, mate! Numbers don’t lie.”

 
No, numbers don’t lie. But people do.

Correlation is fun, isn’t it?

 

Related:

Human ancestry: how to work your own PCA, ADMIXTURE analyses for human evolutionary and genealogical studies

yamna-corded-ware-bell-beaker

I wrote two days ago in the post anouncing the revised version (October 2017) of the Indo-European demic diffusion model, about dumping the information I had on doing PCA and ADMIXTURE analyses as ‘drafts’, without reviewing them, in the new section of this website called Human Ancestry.

I had some time today to review them, and to correct gross mistakes in the texts, so that they might be more usable now

I began to work with free datasets to see if I could learn something more about results of recent Genetic research by working with the available free software. For the moment, I don’t see it necessary to continue working with samples myself, because there are many professionals in Bioinformatics doing an excellent job with their publications – much better than I could do -, and publishing results early (as pre-prints) and with free licenses, which allow us to reuse and modify their material. To work again with their samples seems most of the time like reinventing the wheel.

After all, my interpretation of Indo-European migrations does not depend on my own analysis of free datasets – or on genetic analysis, or on archaeological fieldwork, for that matter – but on the study of all anthropological questions involved. I am actually more interested in Linguistics, and – only marginally – in Archaeology, as is the field of Indo-European Studies in general.

I did find certain interesting aspects that I have commented in the model, though: especially by labelling all samples and reading about them carefully (usually in the supplementary notes of the published papers), you can observe certain patterns and derive some information that others might have missed. Such examples include the Corded Ware outlier from Esperstedt (see more on the Corded Ware migration), or the differences in the three samples from early Khvalynsk.

Now that most data published seem to keep supporting what I have suggested – regarding the more complex nature of the steppe component (so-called ‘yamnaya component‘), and also regarding the migration from Yamna to Bell Beaker, and a migration of a different population (and probably language) with Corded Ware – I don’t find it worthy to spend more of my quite limited time in these tasks.

However, if I need to work again with datasets, I will try to complete the drafts the best I can. Especially regarding F3 Statistics and qpGraph, which I didn’t even try. If you want to help improve the sections, you are welcome of course.

If I find time, I might be of help with your work. And even though modern genealogy does not interest me (for the moment), I guess it can also be relevant to obtain conclusions on more recent migrations, so if I can be of any help to any interesting work, I will do it too.

plot3d-yamna
Plot 3D of datasets Minoans and Mycenaeans + Scythians and Sarmatians, using the same colours as in the Indo-European demic diffusion model.

Related:

  • The concept of “outlier” in studies of Human Ancestry, and the Corded Ware outlier from Esperstedt
  • New Ukraine Eneolithic sample from late Sredni Stog, near homeland of the Corded Ware culture
  • Our monograph on North-West Indo-European (first draft) is out

    I wrote yesterday about the recently updated Indo-European demic diffusion model.

    Fernando López-Menchero and I have published our first draft on the North-West Indo-European proto-language. Our contribution concerns mainly phonetics, and namely two of its most controversial aspects: a common process of laryngeal loss and two series of velars for PIE.

    There is also an updated linguistic model for the Corded Ware substrate hypothesis, which seeks to explain certain similarities between Germanic and Balto-Slavic, and between Balto-Slavic and Indo-Iranian, and potential isoglosses between the three.

    Available links:

    As you probably know, our interest is (and has been for the past 15 years or so, even before our common project) the reconstruction of a North-West Indo-European proto-language, the ancestor of Italo-Celtic, Germanic, and Balto-Slavic. At least since Krahe’s proposal of an Alteuropäische substrate to European hydronymy, some 70 years ago, Indo-Europeanists have been supporting an Old European branch of Proto-Indo-European.

    Old_European_hydronymic_map_for_the_root__Sal-,__Salm-
    Root *sal-, *salm in European river names. Krahe (1949). From Wikipedia.

    However, dialectal divisions were tentative. Since Oettinger, some 30 years ago, we have a clearer picture of a group of closely related dialects, namely Italo-Celtic, Germanic, and Balto-Slavic. Although the nature of Balto-Slavic is somehow contended (for the few scholars who support an Indo-Slavonic group), the minimalist view holds that at least the substrate language of Baltic and Slavic, Holzer‘s Temematic, was part of the North-West Indo-European group.

    A North-West Indo-European (NWIE) proto-language not only solved the controversial question of Pan-European IE hydronymy (clearly of Late Indo-European nature), but also – and more elegantly – the question on the origin of the many fragmentary languages attested in Western Europe, usually attributed to a “Pre-Celtic” or “Pre-Italic” nature depending on their surrounding languages (Venetic has even said to be related to Germanic…).

    proto-indo-european-stages
    Stages of Proto-Indo-European evolution. IU: Indo-Uralic; PU: Proto-Uralic; PAn: Pre-Anatolian; PToch: Pre-Tocharian; Fin-Ugr: Finno-Ugric. The period between Balkan IE and Proto-Greek could be divided in two periods: an older one, called Proto-Greek (close to the time when NWIE was spoken), probably including Macedonian, and spoken somewhere in the Balkans; and a more recent one, called Mello-Greek, coinciding with the classically reconstructed Proto-Greek, already spoken in the Greek peninsula (West 2007). Similarly, the period between Northern Indo-European and North-West Indo-European could be divided, after the split of Pre-Tocharian, into a North-West Indo-European proper, during the expansion of Yamna to the west, and an Old European period, coinciding with the formation and expansion of the East Bell Beaker group.

    Described first mainly in terms of lexical isoglosses, the concept of a NWIE language was then gradually and strongly founded in common grammatical features, contributed to mainly by the German, North American, and Spanish schools (as you know, the British or French schools are quite divided on the nature of Proto-Indo-European itself…). Recent archaeological models pioneered by Harrison and Heyd (2007) showed how this might have happened, with Yamna migrants that evolved as the East Bell Beaker group, and their subsequent expansion into most of Europe.

    Genetics is now clearly supporting such a closely related group, too.

    yamna-bell-beaker
    Yamna – East Bell Beaker migration 3000-2300 BC according to Heyd in Harrison and Heyd (2007).

    The work of Prescott and Walderhaug (1995) on the Pre-Germanic homeland, and the more precise archaeological migration model developed by Prescott clearly established the advent of Bell Beakers in Scandinavia as the key factor for the development of a unitary Pre-Germanic language in Scandinavia during the Dagger Period of the Nordic Late Neolithic.

    The nature of Únětice and Mierzanowice/Nitra cultures as of Bell Beaker absorption of preceding Corded Ware cultures made the identification of the Balto-Slavic homeland in the Lusatian culture as quite likely – and this is now being confirmed with the study of Bronze Age samples, like those of the Tollense battlefield, which cluster closely to West Slavic and East German samples.

    At the time of Marija Gimbutas’ breakthrough model of the “kurgan peoples” a common dialect from this Old European branch was deemed to be ‘Northern European‘ (or ‘Germano-Balto-Slavic’), which greatly influenced her work, supporting an identification of different burial types as stemming from the same source. This model, rejected already some years after Gimbutas’ proposal, has sadly survived to this day because of tradition (due e.g. to the work and influence of Kristiansen, and to some extent Anthony), and for some years (until the advent of ancient DNA) because of the modern distribution of haplogroup R1a in Europe and its relation to the ancient distribution of the Corded Ware culture.

    This traditional model of a ‘Corded Ware -> Bell Beaker expansion of NWIE’ which we also followed until recently, never fit well with the known migrations paths from Yamna (into Balkan Early Bronze Age cultures), with the geographic distribution of Old European hydronymy, or with the guesstimates for Late Indo-European and North-West Indo-European. This compelled us to support a break-up of the proto-language further back in time than warranted by models of language change, and it needed certain unlikely cultural diffusion events over huge areas (because no such migration from Yamna to northern Europe has been attested): along the steppe/forest-steppe zone first, for a diffusion from Yamna into Corded Ware cultures, and along the Danube or the Rhine later, for a diffusion of Corded Ware into Bell Beaker. These models were also based on the wrong interpretation of the first radiocarbon dates of Beakers – placing an origin of the Bell Beaker people in Iberia (which has been rejected in Archaeology, and now also in Genetics).

    Such a ‘Germano-Balto-Slavic’ group faded in Linguistics long ago, with most Indo-Europeanists preferring to talk about late contacts (viz. Celto-Germanic or Italo-Germanic contacts), and for some there is – if any subgroup at all – a core West Indo-European or Italo-Celto-Germanic group, which may be supported by recent genetic research on Bell Beaker peoples, with the Beaker group of the Netherlands being the key. Our research on the potential language spoken by Corded Ware peoples – most likely related to Uralic, from an Indo-Uralic community from the Pontic-Caspian steppe – can elegantly explain the isoglosses that both European dialects share.

    copper-age-late-bell-beaker
    Diachronic map of Late Copper Age migrations including Classical Bell Beaker (east group) expansion from central Europe ca. 2600-2250 BC