Forces driving grammatical change are different to those driving lexical change

Grammar change

A new paper at PNAS, Evolutionary dynamics of language systems, by Greenhill et al. (2017).

Significance

Do different aspects of language evolve in different ways? Here, we infer the rates of change in lexical and grammatical data from 81 languages of the Pacific. We show that, in general, grammatical features tend to change faster and have higher amounts of conflicting signal than basic vocabulary. We suggest that subsystems of language show differing patterns of dynamics and propose that modeling this rate variation may allow us to extract more signal, and thus trace language history deeper than has been previously possible.

Abstract

Understanding how and why language subsystems differ in their evolutionary dynamics is a fundamental question for historical and comparative linguistics. One key dynamic is the rate of language change. While it is commonly thought that the rapid rate of change hampers the reconstruction of deep language relationships beyond 6,000–10,000 y, there are suggestions that grammatical structures might retain more signal over time than other subsystems, such as basic vocabulary. In this study, we use a Dirichlet process mixture model to infer the rates of change in lexical and grammatical data from 81 Austronesian languages. We show that, on average, most grammatical features actually change faster than items of basic vocabulary. The grammatical data show less schismogenesis, higher rates of homoplasy, and more bursts of contact-induced change than the basic vocabulary data. However, there is a core of grammatical and lexical features that are highly stable. These findings suggest that different subsystems of language have differing dynamics and that careful, nuanced models of language change will be needed to extract deeper signal from the noise of parallel evolution, areal readaptation, and contact.

This is in line with the studies by Bendt, like Adaptive Communication: Languages with More Non-Native Speakers Tend to Have Fewer Word Forms, which suggest a simplification of grammar with language contact.

It might then give further support to my proposal of Uralic as the Corded Ware substrate – common to Balto-Slavic and Indo-Iranian -, since they are the only Late Indo-European branches that clearly retain the grammatical complexity in word forms, which – together with their shared phonetic isoglosses (also present partially between Balto-Slavic and Germanic) -, put them nearer to a complex, potentially related Uralic (or other Indo-Uralic) branch.

On the other hand, the finding of a greater stability of lexicon gives further support to the concept of a North-West Indo-European group, since one of its foundations (the main one originally) is the shared vocabulary between Italo-Celtic, Germanic, and Balto-Slavic.

Featured image: from the article (copyrighted), “Map showing locations of languages in this study. The phylogenies show the maximum clade credibility tree of the Austronesian languages in our sample. Each phylogeny is colored by the average rate of change, with branches showing more change colored redder, while bluer branches show reductions in rate. Branches with significant shifts are annotated with an asterisk, and the languages showing significantly different rates of change in their grammatical data are located on the map”.

Related:

New preprint papers on Finland’s population history and disease, skin pigmentation in Africa, and genetic variation in Thailand hunter-gatherers

finland-genetics

New and interesting research these days in BioRxiv:

Haplotype sharing provides insights into fine-scale population history and disease in Finland, by Martín et al. (2017):

Finland provides unique opportunities to investigate population and medical genomics because of its adoption of unified national electronic health records, detailed historical and birth records, and serial population bottlenecks. We assemble a comprehensive view of recent population history (≤100 generations), the timespan during which most rare disease-causing alleles arose, by comparing pairwise haplotype sharing from 43,254 Finns to geographically and linguistically adjacent countries with different population histories, including 16,060 Swedes, Estonians, Russians, and Hungarians. We find much more extensive sharing in Finns, with at least one ≥ 5 cM tract on average between pairs of unrelated individuals. By coupling haplotype sharing with fine-scale birth records from over 25,000 individuals, we find that while haplotype sharing broadly decays with geographical distance, there are pockets of excess haplotype sharing; individuals from northeast Finland share several-fold more of their genome in identity-by-descent (IBD) segments than individuals from southwest regions containing the major cities of Helsinki and Turku. We estimate recent effective population size changes over time across regions of Finland and find significant differences between the Early and Late Settlement Regions as expected; however, our results indicate more continuous gene flow than previously indicated as Finns migrated towards the northernmost Lapland region. Lastly, we show that haplotype sharing is locally enriched among pairs of individuals sharing rare alleles by an order of magnitude, especially among pairs sharing rare disease causing variants. Our work provides a general framework for using haplotype sharing to reconstruct an integrative view of recent population history and gain insight into the evolutionary origins of rare variants contributing to disease.

finland-migration-haplotype
Migration rates and haplotype sharing within Finland and between neighboring countries. A) Map of regional Finnish, Swedish, and Estonian birthplaces Purple triangle indicates St. Petersburg, Russia. Hungary not shown. 1 Finnish, Swedish, and Estonian region labels are shown in Table S3. B) Principal components analysis (PCA) of unrelated individuals, colored by birth region as shown in A) if available or country otherwise. C-D) Migration rates inferred with EEMS. Values and colors indicate inferred rates, for example with +1 (shades of blue) indicating an order of magnitude more migration at a given point on average, and shades of orange indicating migration barriers. C) Migration rates among municipalities in Finland. D) Migration rates within and between Finland, Sweden, Estonia, and St. Petersburg, Russia. Available under a CC-BY 4.0 International license.

Interesting to understand this paper is the whole research published by the Institute for Molecular Medicine Finland (FIMM): their website contains detailed research on Finland’s recent genetic history.

NOTE: The featured image of this article contains three figures from the FIMM (License CC-BY 4.0). Left: Position of the points represents the locations of 1042 Finnish individuals. By clustering the individuals into two groups based on genome data we see a split between eastern (blue) and western (red) parts. Individuals who show considerable relatedness to both groups have been colored with cyan. Both parents of each individual were born close to each other and based on the parents’ birth years we can infer that we are looking at the genetic structure present in Finland before 1950s. Center: An estimated borderline of the Treaty of Nöteborg on top of the map from the left. The border line is drawn between Jääski (28.92 N, 61.04 E) and Pyhäjoki (24.26 N, 64.46 E). Right: The settlement border divides Finland into the early settlement region (to west and south of the border) and the late settlement region (to east and north of the border) (Jutikkala 1933, s. 91). We see that Southern Savo (in south-eastern part of the early settlement) is among the only parts of the early settlement region that is dominated by the eastern genetic group. Information from Matti Pirinen and Sini Kerminen, 24.5.2017.

An Unexpectedly Complex Architecture for Skin Pigmentation in Africans, by Martin et al (2017):

Fewer than 15 genes have been directly associated with skin pigmentation variation in humans, leading to its characterization as a relatively simple trait. However, by assembling a global survey of quantitative skin pigmentation phenotypes, we demonstrate that pigmentation is more complex than previously assumed with genetic architecture varying by latitude. We investigate polygenicity in the Khoe and the San, populations indigenous to southern Africa, who have considerably lighter skin than equatorial Africans. We demonstrate that skin pigmentation is highly heritable, but that known pigmentation loci explain only a small fraction of the variance. Rather, baseline skin pigmentation is a complex, polygenic trait in the KhoeSan. Despite this, we identify canonical and non-canonical skin pigmentation loci, including near SLC24A5, TYRP1, SMARCA2/VLDLR, and SNX13 using a genome-wide association approach complemented by targeted resequencing. By considering diverse, under-studied African populations, we show how the architecture of skin pigmentation can vary across humans subject to different local evolutionary pressures.

Contrasting maternal and paternal genetic variation of hunter-gatherer groups in Thailand, by Kutanan et al. (2017):

The Maniq and Mlabri are the only recorded nomadic hunter-gatherer groups in Thailand. Here, we sequenced complete mitochondrial (mt) DNA genomes and ~2.364 Mbp of non-recombining Y chromosome (NRY) to learn more about the origins of these two enigmatic populations. Both groups exhibited low genetic diversity compared to other Thai populations, and contrasting patterns of mtDNA and NRY diversity: there was greater mtDNA diversity in the Maniq than in the Mlabri, while the converse was true for the NRY. We found basal uniparental lineages in the Maniq, namely mtDNA haplogroups M21a, R21 and M17a, and NRY haplogroup K. Overall, the Maniq are genetically similar to other negrito groups in Southeast Asia. By contrast, the Mlabri haplogroups (B5a1b1 for mtDNA and O1b1a1a1b and O1b1a1a1b1a1 for the NRY) are common lineages in Southeast Asian non-negrito groups, and overall the Mlabri are genetically similar to their linguistic relatives (Htin and Khmu) and other groups from northeastern Thailand. In agreement with previous studies of the Mlabri, our results indicate that the Malbri do not directly descend from the indigenous negritos. Instead, they likely have a recent origin (within the past 1,000 years) by an extreme founder event (involving just one maternal and two paternal lineages) from an agricultural group, most likely the Htin or a closely-related group.

Related:

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

eneolithic-europe

Just one day after publishing the draft of the Indo-European demic diffusion model, 3rd version, Mathieson et al. (2017) have updated some information in a new version of their article, including a new interesting sample from late Sredni Stog. It gives support to what I predicted, regarding the potential origin of the third Corded Ware horizon.

After my first version, findings in Olalde et al. (2017) and Mathieson et al. (2017) supported some of my predictions. Now after my third, their new data also supports another prediction. Because the model is based on solid linguistic and archaeological models. Here is an excerpt from the Indo-European demic diffusion model, 3rd ed. (pp. 55-56):

At the end of the Trypillian culture, herding/hunting trends intensified, and the agricultural system collapsed, with people moving to the steppe zone, as confirmed by the presence of numerous graves to the south (Rassamakin 1999). At the same time, the Trypillian world absorbed a foreign tradition related to materials of settlement sites of the Dnieper steppes – such as the late Sredni Stog culture –, like cord impressions and burial rites similar to the later Corded Ware culture, marking also the transformation of decors and changes in their interpretation (Palaguta 2007).

The similarity in burial rituals between Yamna and Corded Ware made Gimbutas define a common “Kurgan people”, whose relationship has also been long supported by Kristiansen (Kristiansen 1989; Kristiansen et al. 2017). An equivalence of both burial rites has been, however, rejected (Häusler 1963, 1978, 1983), and it is generally agreed that the Yamna culture did not expand to the north of the Tisza River.

The importance of horse exploitation in Deriivka, in the forest-steppe zone of the north Pontic region along the Dnieper region, during the Middle Eneolithic period (probably ca. 3700-3530 BC), suggests that horses played a significant role in the life of this Sredni Stog community (Anthony and Brown 2003). In its late period (ca. 4000-3500 BC), this culture had adopted corded ware pottery, and stone battle-axes.

However, this [sic] western steppe peoples were mainly hunters (Rassamakin 1999), and the ‘herding skill’ essential for wild horse domestication seems absent (Kuzmina 2003). All this has been confirmed with zooarchaeological evidence and new molecular and stable isotope results, suggesting an absence of horse domestication in territories of the late Sredni Stog culture in the north Pontic steppe (Mileto et al. 2017), before the advent of migrants from the Indo-European-speaking Repin culture.

The new sample described in Mathieson et al. (2017), dated ca. 4200 BC (but within a wide range, 5000-3500 BC) is from a site classified as of late Sredni Stog (although potentially from Post-Mariupol / Kvitjana), a culture of hunters who probably did not breed domesticated horses (even after the period of conquest and dominance of Suvorovo-Novodanilovka chiefs, from Indo-Hittite-speaking early Khvalynsk, who had domesticated horses), and – more importantly – is of R1a-M417 lineage, shows high so-called “Yamna component” in ADMIXTURE, and clusters among Corded Ware samples in PCA approximately a thousand years before this culture’s expansion. Information from the supplementary material:

An Eneolithic cemetery of the Sredny Stog II culture was excavated by D. Telegin in 1955-1957 near the village of Alexandria, Kupyansk district, Kharkov region on the left bank of the river Oskol. A total of 33 individuals were recovered. Based on craniometric analysis (I.Potekhina 1999) it was suggested that the Eneolithic inhabitants of Alexandria were not homogeneous and resulted from admixture of local Neolithic hunter-gatherers and early farmers, possibly Trypillian groups. We report genetic data from one individual: I6561

pca-mathieson_ukraine_eneolithic
PCA, Admixture of Ukraine Eneolithic and other samples from Mathieson et al. (2017)

Another individual from Eneolithic Ukraine (of R1b1 xM269 lineage) clusters quite closely with Neolithic samples from the Baltic, which points to the strong connection between both – southern and northern – regions of east-central Europe before the period of great Chalcolithic expansions, and the potential origin of the spread of R1b (xM269) lineages with the Corded Ware culture.

The so-called ‘Yamna component’ – an infamous name which, as expected, is turning out to be very wrong – has been found quite elevated in this sample, previous and completely unrelated to the Yamna culture and its expansion, and similar to the (later) Corded Ware samples. In fact, we are seeing that Corded Ware samples are actually clustering closely with east-central Europe (excluding the CWC outlier), and not with Yamna and other Indo-European-speaking steppe cultures.

pca-mathieson2-ukraine-eneolithic
‘Yamna component’ (in yellow) in the North-West Pontic Steppe and the Balkans, including Eneolithic Ukraine samples

It will be fun to see the mess that certain researchers have made (and will still make in the near future) of their findings coupled with the concept of “Yamna component”, when trying to describe the “proxy ancestral populations” of European Copper Age and Bronze Age cultures… Difficult times ahead for many, after the collapse of the simplistic Yamna -> Corded Ware -> Bell Beaker genetic model laid out since Haak et al. (2015) and Allentoft et al. (2015).

[EDIT 27 September 2017] Not directly related, but here is today’s interesting discussion on Twitter surrounding the ancestral populations of the “Yamnaya component”, for illustration of the discussions to come when this ancestry is divided into different, more precise, older (Neolithic) steppe components, and these in turn shown to contribute to different European and Asian Chalcolithic and Bronze Age cultures:

Given the variance found in the three samples from Eneolithic Ukraine (comparable to the variance found in east Bell Beaker samples), we may now be getting closer to the precise territory and culture where the Corded Ware culture might have formed, which cannot be much further from the Dnieper-Dniester region before the Yamna expansion to the west ca. 3300 BC, judging from the elevated steppe component.

It seems, because of the proximity of both cultures and the similar dates of their migrations, that the westward expansion of the Yamna culture may have indeed provided an important push (among some strong ‘pull’ forces) for peoples of the expansion of the Corded Ware culture.

eneolithic_Caucasus
Diachronic map of Eneolithic migrations in the Caucasus ca. 4000-3100 BC

It keeps being demonstrated that archaeologists like Anthony, Heyd, Mallory, etc. were right where others tried to interpret admixture based on few samples and their own imagination, without any knowledge (or interest) whatsoever about Archaeology or Linguistics.

So Genetics reinforces the solidest models of Archaeology and Linguistics? Professional academics being mostly right in their careful research, and amateur geneticists playing with software being wrong? Who would have thought… More and more papers help thus shut up naysayers who state (again and again) that new algorithms are here to revolutionise these academic fields.

As Heyd predicted more than 10 years ago, and as many pointed out in terms of linguistic influence (like Mallory or Prescott) the transformation of Yamna settlers into the east Bell Beaker culture, and this culture‘s spread into western and northern Europe, must be noticed in genetic investigation.

The expansion of peoples is known to be associated with the spread of a certain admixture component + the expansion and reduction in variability of a haplogroup (i.e. few male lineages are usually more successful during the expansion): Neolithic farmers from the Middle East expanding with haplogroup G2a; Natufian component (Levant hunter-gatherers or later, Neolithic farmers) and haplogroup E southward into Africa; CHG component expansion with haplogroup J; WHG expansion into east Europe with haplogroup R1b; etc.

There were (at least) two main expansion processes involving Proto-Indo-European: one causing the branching off of the language ancestral to Anatolian, and another during the spread of Late Indo-European dialects. Based on this, and on known archaeological models, I have predicted since the first version of the demic diffusion model:

  • Based on haplogroups found until then in Yamna (R1b-M269), Corded Ware (R1a-M417, especially Z645), and Bell Beaker (R1b-L151):
    • that mainly R1b-L23 (especially L51) lineages and more steppe admixture would be found in east Bell Beaker – confirmed some two months after my publication by Olalde et al. (2017);
    • and that mainly R1a-M417 (especially Z645) subclades will be found in Corded Ware samples.
  • Based on the finding of “Yamna component” in the Corded Ware culture: that this admixture must have come from somewhere else. I pointed out to eastern Europe, including the forest and forest-steppe zone especially in the natural continuum of the Dniester-Dnieper region. Especially after Mathieson et al. (2017), in my second and third versions of the model, I have more specifically suggested a southern origin in the region, nearer to where the CHG ancestry must have come from (the Caucasus and cultures formed in contact with it), according to mainstream archaeological data, i.e. cultures of the North Pontic steppe / steppe-forest. But of course, until more samples are available, more CHG ancestry in other cultures of the Forest Zone cannot be discarded.

For the vast majority of academics, more samples (regionally proportioned) are needed only from early Corded Ware, as we have from Bell Beaker: if they are (as expected) mostly R1a-M417, then everything is clear, and it will finally mean the end for the tiring, now almost ‘traditional’ association R1a – Proto-Indo-European. Some more samples from the potential homeland of the third Corded Ware horizon, most likely Ukraine (Podolia and Volynia regions), nearer to the time of the Corded Ware expansion, would also be great, to locate the actual ancestral population of Corded Ware migrants – recognisable by the main presence of haplogroup R1a-Z645 (formed ca. 3500 BC), and elevated “Yamna component” before the arrival of the Yamna culture…

If, however, early Corded Ware samples of R1b-L23 subclades are found in certain quantity, especially old samples from east-central Europe (excluding Yamna migrants along the Prut), the tricky question of Late Indo-European cultural diffusion will remain: Did Corded Ware peoples adopt a Late Indo-European language from clans of R1b-L23 lineages? That is what Kristiansen and Anthony have been betting for, a cultural diffusion, caused by:

  • A long-lasting contact, according to Kristiansen (1989,…,2017). He defends that Sredni Stog adopted the language – but obviously not the same culture – from the east, but that it is a genetic and cultural mix from Globular Amphora, Trypillia, and steppe cultures. This has been Kristiansen’s model for almost 30 years, and it follows Marija Gimbutas’ outdated theory of the “Kurgan people”.
  • A rapid change according to Anthony (2007). He associates the adoption of Pre-Germanic with the domination of Yamna chiefs over Usatovo people, and the adoption of Balto-Slavic by the people from (Corded Ware) Middle Dnieper group because of the technical superiority of neighbouring Yamna herders.

Linguistics, with the growing support of a North-West Indo-European group, points clearly to a European expansion of a community speaking the ancestral language of Italo-Celtic, Germanic, and probably Balto-Slavic. Archaeology, too, showed migration from Yamna only to south-eastern Europe (correcting Gimbutas’ Kurgan model) and later with east Bell Beaker mainly into central, western, and northern Europe.

Even Kristiansen admits that only after the arrival of Bell Beaker in Scandinavia was a linguistic community (i.e. Germanic) formed – although he places the center of gravity in Úněticean influence, and (yet again) a cultural diffusion event into the Danish Dagger period.

Because of more and more data contrasting with old theories, some have elected to develop weak, indemonstrable links, to keep supporting e.g. Gimbutas’ concept of “Kurgan people” in Archaeology, and a sudden, early expansion of all PIE dialects at once in Linguistics. It seems that, after so much fuss about the (misleading) ‘Yamna component’ concept – and so many far-fetched assumptions by amateur geneticists -, the Corded Ware connection will once again hinge on weak, indemonstrable cultural diffusion theories, be it ‘Kurgan peoples’ (including now, of course, Eneolithic cultures of Ukraine) or any culture from eastern Europe that will reveal some close samples to Corded Ware migrants, in terms of PCA, ADMIXTURE, or haplogroup.

So once we find mainly R1a-Z645 in more Corded Ware samples (and this haplogroup and more “Yamna component” in non-Yamna cultures of Eneolithic Ukraine, and potentially Poland or Belarus) we all may finally expect a peaceful acceptance of reality, at least in Genetics? Nope. No siree. Nein. Not then, not ever.

Why? Because some people want their paternal lineage to have lived in their historical region, and spoken their historical language, since time immemorial. It won’t matter if Archaeology, Linguistics, Genetics, etc. don’t support their claims: if they need to use some aspects of admixture, or haplogroups (or a combination of them) from carefully selected samples instead of looking at the whole picture; if they have to support that Indo-Europeans came from a culture different than Yamna, in- or outside of the steppe or forest-steppe, be it the Balkans, Anatolia, Armenia, or the Moon; if their proto-language should then come directly from Indo-Hittite, or from a Germano-Slavonic, or Indo-Slavonic, or Indo-Germanic group, or whatever invented dialectal branch necessary to fit their model, or if they have to support the ‘constellation analogy’ of Clackson, or thousands of years of development for each branch; etc. They will support whatever is necessary.

And this adaptation, obviously, has no end. It’s stupid, I know. But that’s how we are, how we think. We have seen that these sad trends continue no matter what, for decades, and not only regarding Indo-European. Some common examples include:

  • Indo-Aryan-speaking Indians defending an autochthonous origin of R1a and Indo-European; as well as the ‘opposite’ autochtonous continuity theory of Dravidian-speaking Indians (based on ASI ancestry, haplogroup R2, mtDNA haplogroup M, or whatever is at hand).
  • Western Europeans defending an autochthonous origin of the R1b haplogroup, with a Palaeolithic or Mesolithic origin, including the language, viz. the recent Indo-European from the Atlantic façade theories (in the Celtic from the West series, by Koch and Cunliffe); the now fading Palaeolithic Continuity Theory; and many other forgotten Eurocentric proposals; as well as the more recent informal hints of a central European/Balkan homeland based on the Villabruna cluster and south-eastern Mesolithic finds, which is at risk of being related to a Balkan origin of Proto-Indo-European
    • There is also the ‘opposite’ theory of the autochthonous origin of the Basques, including Proto-Iberians and potentially other peoples like Paleo-Sardinians, based on the previously popular Vasconic-Uralic hypothesis (and an ancient Europe divided into R1b and N1c1 haplogroups), which is still widely believed in certain regions.
  • Finno-Ugric speakers of N1c1 lineage defending an autochtonous origin of the lineage and language in eastern Europe.
  • Nordic speakers supporting the autochthonous nature of Germanic and haplogroup I1 to Scandinavia.
  • Armenian speakers delighted to see a proposal of Indo-European homeland in the Armenian highlands, be it supported by glottalic consonants, CHG ancestrty, R1b (xM269) or J lineages…
  • Greek speakers now willing to support continuity of haplogroup J as a ‘native’ Greek lineage, of people speaking Proto-Greek (and in earlier times PIE), because of two Minoan, and one Mycenaean samples found in Lazaridis et al. (2017).
  • Even Turks linking Yamna with the expansion of Turkic languages. That one is fun to read, almost like a parody for the rest – substituting “Indo-European” for “Turkic”.
  • For years, a lot of people – me included (at least since 2005) – believed, because of modern maps of R1a distribution, that R1a and Corded Ware are the vector of Indo-European languages. For those of us who don’t have any personal or national tie with this haplogroup, this notion has been easy to change with new data. For others, it obviously isn’t, and it won’t be.
R1a_distribution_Eurasia
Modern R1a distribution in Eurasia (Wikipedia, 2008). The typical, simplistic map we relied on in the 2000s to derive wrong conclusions based on Genetics, conclusions which are sadly still alive and kicking…

For all these people, a sample, result, or conclusion from any paper, just dubiously in favour, means everything, but a thousand against mean nothing, or can be reinterpreted to support their fantasies.

The Kossinian autochthonous continuity” crap permeates this relatively new subfield of Human Evolutionary Genetics, as it permeated Indo-European studies (first Linguistics, then Archaeology) in its infancy. It seems to be a generalised human trend, no doubt related to some absurd inferiority complex, mixed with historical romanticism, a certain degree of chauvinism, and (falling in the eternal Godwin’s Law of our field) some outdated, childish notion of ‘supremacy’ linked with the expansion of the own language and people.

Such simplistic and popular models are also lucrative, judging by the boom in demand for DNA analysis, which companies embellish with modern fortune tellers (or fortune tellers themselves sell for a price), promising to ascertain your ‘ancestry proportions’ using automated algorithms, so that you don’t have to get lost in complex genetic data and prehistoric accounts, which can’t help you define your “ethnicity”…

Some just don’t want to realize that the spread of prehistoric languages (like Late Indo-European dialects) was a complex, non-uniform, stepped process, devoid of modern romantic concepts, which in genetic terms necessarily included later founder effects and cultural diffusions, so that no one can trace their haplogroup, lineage, family, region, or country to any single culture, language, or ethnic group. The same, by the way, can be said of peoples and countries in historic times.

As I said before, we shall expect supporters of the Kurgan model (and thus the expansion of R1a-Z645 with Yamna) to wait for just one sample of R1a-M417 in Yamna and/or Bell Beaker (which will eventually be found), and just one sample of R1b-M269 in Corded Ware (which will also eventually be found), to blow the horn of victory in this naïve competition against time, general knowledge, and (essentially) themselves.

A sad consequence of how we are is that, because of the obvious influence of these stupid modern ethnolinguistic agendas, because we are not all rowing in the same direction, genetic results and conclusions are still perceived as far-fetched and labile, and thus most archaeologists and linguists prefer not to include genetic results in their investigation. And those who dare to do so, are badly counselled by those who go with the tide, so that their papers become almost instantly outdated.

Related:

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

pca-yamna-corded-ware

While writing the third version of the Indo-European demic diffusion model, I noticed that one Corded Ware sample (labelled I0104) clusters quite closely with steppe samples (i.e. Yamna, Afanasevo, and Potapovka). The other Corded Ware samples cluster, as expected, closely with east-central European samples, which include related cultures such as the Swedish Battle Axe, and later Sintashta, or Potapovka (cultures that are from the steppe proper, but are derived from Corded Ware).

I also noticed after publishing the draft that I had used the wording “Corded Ware outlier” at least once. I certainly had that term in mind when developing the third version, but I did not intend to write it down formally. Nevertheless, I think it is the right name to use.

pca-yamna-corded-ware
PCA of dataset including Minoans and Mycenaeans, and Scythians and Sarmatians. The graphic has been arranged so that ancestries and samples are located in geographically friendly axes similar to north-south (Y), east-west(X). Symbols are used, in a simplified manner, in accordance with symbols for Y-DNA haplogroups used in the maps. Labels have been used for simplification of important components. Areas are drawn surrounding Yamna, Poltavka, Afanasevo, Corded Ware (including samples from Estonia, Battle Axe, and Poltavka outlier), and succeeding Sintashta and Potapovka cultures, as well as Bell Beaker. Corded Ware sample I0104, from Esperstedt, has also been labelled.

Outlier in Statistics, as you can infer from the name, is a sample (more precisely an observation) that lies distant to others. It is a slippery concept in Human Evolutionary Biology, because it has no clear definition, and it is thus dependent on a certain degree of subjective evaluation. It seems to be mainly based on a combination of PCA and ADMIXTURE analyses, but should obviously be dependent on the number of samples available for a certain culture, and the regional distribution of the samples available.

We have thus certain clear cases, like the Poltavka outlier, of R1a-M417 lineage, clustering close to Corded Ware (and Sintashta, and Potapovka) samples, but far from other R1b-L23 samples from Poltavka or Yamna cultures, from neighbouring regions in the steppe.

We have also less clear observations, like Balkan Chalcolithic samples, which may or may not have been part of different cultural groups (say, related to the Suvorovo-Novodanilovka expansion, or not), which may justify their differences in ancestral components in ADMIXTURE, and in their position in PCA.

And we have a Yamna sample from western Ukraine, which – unlike the other two available samples – clusters “to the south” of east Yamna samples. Taking into account the Yamna sample from Bulgaria, clustering closely with south-eastern European samples, could you really call this an outlier? Two outliers out of four western Yamna samples? Well, maybe. If you take east and west Yamna from the steppe as a whole, and exclude the Yamna sample from Bulgaria, of course you can. Whether that classification is useful, or actually hinders a proper interpretation of western Yamna samples, and of the “Yamna component” seen in them, is a different story…

pca-yamna
PCA for European samples of Mathieson et al. (2017)

But what then about the Corded Ware male from Esperstedt, labelled I0104, dated ca. 2430 BC, which clusters among contemporaneous steppe (Poltavka) samples, and has the greatest proportion of ‘Yamna component’ in ADMIXTURE? After all, it is different in both respects from any other Corded Ware individual – including the oldest samples available, from Latvia (ca. 2885 BC) and Tiefbrunn (ca. 2755 BC).

This sample is one of the direct links between the steppe and Corded Ware in late times, and has been the main reason for the confusion a lot of people seem to have about the “Yamna component” in Corded Ware, with some supporting a direct migration from one into the other, and a few even daring to say that “Corded Ware is indistinguishable from Yamna”(!?).

His family members – all males of haplogroup R1a-M417 (like I0104 and most males from the Corded Ware culture) -, few generations later, show a decreased Yamna component, which clearly indicates that this individual’s admixture came directly from the steppe, and most likely from one or multiple female ancestors. That is compatible with the nomadic nature of the Corded Ware culture (and its known exogamy practices), which connected central Europe with the steppes, up to the North Caspian region.

If labelling other samples as outliers may be interesting to improve the conclusions one can obtain from genetic research, labelling this sample is, in my opinion, essential, to avoid certain strong misconceptions about the origin of the Corded Ware culture.

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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.

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