The future of the Reich Lab’s studies and interpretations of Late Indo-European migrations

yamna-corded-ware-bell-beaker-reich

Short report on advances in Genomics, and on the Reich Lab:

Some interesting details:

  • The Lab is impressive. I would never dream of having something like this at our university. I am really jealous of that working environment.
  • They are currently working on population transformations in Italy; I hope we can have at last Italic and Etruscan samples.
  • It is always worth it to repeat that we are all the source of multiple admixture events, many of them quite recent; and I liked the Star Wars simile.
  • Also, some names hinting at potential new samples?? Zajo-I, Chanchan, Gurulde?, Володарка (Ukraine – medieval?), Autodrom, Облевка, Кресты, Кудуксай (Ural region, palaeo-metal?), Золкут, etc.
reich-lab-samples
Ancient DNA sample bag?

On the bad aspect, they keep repeating the same “steppe ancestry” meme (in the featured image above, or the one below). I know this is the news report (i.e. science communication), not exactly the Reich Lab, but these maps didn’t appear out of the blue.

steppe-admixture-reich
Steppe ancestry distribution in Europe, according to PBS.

Interesting for future interpretations is the whiteboard behind David Reich’s back (apparently they like to keep relevant information on whiteboards…):

reich-indo-european-tree
Whiteboard behind David Reich’s back (at his office?).

It seems that while the Copenhagen group will still be bound (see here) by the Gimbutas/Kristiansen starting point, the Reich Lab will remain bound by Anthony’s selection of Ringe’s (2002) glottochronological model, and they will try to make genomic data fit in with it.

In fact, the whiteboard doesn’t even include Ringe’s link of Germanic with Italo-Celtic, which could maybe hint at Anthony’s recent change of heart? (i.e. Yamna Hungary -> Corded Ware). That would mean still less Linguistics (if glottochronology can be called that), and more Archaeology…

anthony-ringe-migration-model
Image from Anthony & Ringe (2015). “The Proto-Indo-European homeland, with migrations outward at about 4200 BCE (1), 3300 BCE (2), and 3000 BCE (3a and 3b). A tree diagram (inset) shows the pre-Germanic split as unresolved. Modified from Anthony (2013).”

I don’t know why university labs need to do this: To select the linguistic model preferred by a single archaeologist, which happens to be the lead archaeologist of the group, and then try to make genetic data agree again and again with that model. I guess it is a strategic question, and has to do with granting continued contacts with archaeological sites, and access to samples from them?

I understand none of them will try to learn ancient languages, too much work probably. But, wouldn’t it have been more scientifish, at least, to depart from, say, three or four reasonable potential linguistic models (that is, from Indo-Europeanists), and from there discuss the best potential fits for the current genomic data in each paper?

This is, for example, how the Heyd (archaeologist) + German/Spanish Indo-Europeanist schools would look like:

yamnaya-heyd-dunkel
Yamnaya expansion coupled with Meid’s (1975) description of three stages of Proto-Indo-European development (as interpreted by Adrados 1998) and depiction of Heyd’s proposal of Yamna expansion.

Wouldn’t you say it could have fitted the statistical and Y-DNA data seamlessly, in contrast to Gimbutas/Trager (i.e. Kristiansen today), or to Anthony/Ringe?

NOTE. I would say the mainstream German school follows Meid’s (1975) three-stage theory coupled with Dunkel’s (e.g. 1997) nomenclature. The Spanish school follows Adrados, who has repeated ad nauseam that he was the first to mention the three-stage theory in conferences and papers previous to and coincident with Meid’s proposal (see his latest JIES article, a paper available in Scribd). In any case, Spanish and German scholars have been working hand in hand in accepting and developing a general linguistic model similar to the one above.

Archaeological theories like those of Heyd or Mallory for Yamna and Bell Beaker (in contrast to Kristiansen or Anthony), and Prescott and Walderhaug for Bell Beaker and Germanic (contrasting with Kristiansen and Iversen) are compatible with this German/Spanish model.

The French school is non-existent on the homeland matter, Italian scholars seem to be behind even in the description of Anatolian as archaic (probably related to the general wish to have Latin as derived from Vergil’s Troy), Russian scholars are still working with Nostratic and Mesolithic expansions, and Leiden, as the leading IE publisher worldwide today, is full of very different ‘divos’, each with his own pet theory (some obviously agreeing with the German/Spanish model; and especially interesting is that some of them are strong supporters of an Indo-Uralic proto-language).

The English-speaking world, on the other hand, has seen the most varied models being either proposed or translated into its language, with the most popular ones being those publicized by archaeologists (Winfred P. Lehmann being one of the noteworthy exceptions), which may explain why for some people (archaeologists or geneticists) linguistics seems more like a game. It is to be assumed that these same people haven’t taken a look at the dozens of genetic papers published to date – and hundreds of archaeological papers using a bit of linguistics to support their models – , and how wrong they have all been in their interpretations, or else they would realize that genomics does (sadly) not really look like a serious discipline at all right now among most linguists, and among many archaeologists either…

Thus, instead of comparing the main theories on Proto-Indo-European (i.e. linguistics->archaeology->genetics), which would have offered the most stable framework to assess potential prehistoric ethnolinguistic identifications, they keep using a single, simplistic language tree liked by an archaeologist, and trying to fit genetic data to it, while also adapting archaeology to genetics, i.e. genetics->archaeology->linguistics; which, as you can imagine, is not going to convince any linguist.

Especially disappointing is that the world’s leading genetic lab still relies on a marginal proposal based on glottochronology, the homeopathy of linguistics… At least in that regard everyone should know better by now.

Also, they keep interacting with the wrong audience: instead of trying to engage linguists into the real homeland and dialectal quest, to keep Genomics a serious discipline among academics, they tend to discuss with politically- or racially-motivated people, which is probably also in line with strategic decisions.

In the example below, we see the main author of their recent paper on Indo-Iranian migrations seeking once again interaction, this time through “news” promoted by Hindu nationalist bigots, so that – even if that makes them look more neutral in the eyes of those who may allow access to Indian samples – , in the end, we see in genomics a fictitious revival of the “AIT vs. OIT debate” dead long ago in linguistics and archaeology (anywhere but in India).

Pretty disappointing to see these trends; so much effort and time invested in futile discussions and infinitely reworked doomed glottochronological or 19th-century models, when it is the fine-scale population structure of expanding Yamna peoples what we should be discussing now, and thus Late PIE dialectalisation with offshoots Afanasevo, East Bell Beaker, Balkan Bronze Age, and Sintashta/Potapovka; as well as Corded Ware evolution in Uralic-speaking territory.

EDIT (7 JUN 2018): Some parts of the text have been corrected or slightly modified.

Related:

David Reich on social inequality and Yamna expansion with few Y-DNA subclades

Interesting article from David Reich that I had missed, at Nautilus, Social Inequality Leaves a Genetic Mark.

It explores one of the main issues we are observing with ancient DNA, the greater reduction in Y-DNA lineages relative to mtDNA lineages, and its most likely explanation (which I discussed recently).

Excerpts interesting for the Indo-European question (emphasis mine):

Gimbutas’s reconstruction has been criticized as fantastical by her critics, and any attempt to paint a vivid picture of what a human culture was like before the period of written texts needs to be viewed with caution. Nevertheless, ancient DNA data has provided evidence that the Yamnaya were indeed a society in which power was concentrated among a small number of elite males. The Y chromosomes that the Yamnaya carried were nearly all of a few types, which shows that a limited number of males must have been extraordinarily successful in spreading their genes. In contrast, in their mitochondrial DNA, the Yamnaya had more diverse sequences.9 The descendants of the Yamnaya or their close relatives spread their Y chromosomes into Europe and India, and the demographic impact of this expansion was profound, as the Y-chromosome types they carried were absent in Europe and India before the Bronze Age but are predominant in both places today.13

This Yamnaya expansion also cannot have been entirely friendly, as is clear from the fact that the proportion of Y chromosomes of steppe origin in both western Europe14 and in India15 today is much larger than the proportion of the rest of the genome. This preponderance of male ancestry coming from the steppe implies that male descendants of the Yamnaya with political or social power were more successful at competing for local mates than men from the local groups. The most striking example I know is from Iberia in far southwestern Europe, where Yamnaya-derived ancestry arrived suddenly at the onset of the Bronze Age between 4,500 and 4,000 years ago. Daniel Bradley’s laboratory and my laboratory independently produced ancient DNA from individuals of this period.14 We find that in the first Iberians with Yamnaya-derived ancestry, the proportion of Yamnaya ancestry across the whole genome is almost never more than around 15 percent. However, around 90 percent of males who carry Yamnaya ancestry have a Y-chromosome type of steppe origin that was absent in Iberia prior to that time. It is clear that there were extraordinary hierarchies and imbalances in power at work in the Yamnaya expansions.

David Reich clearly doesn’t give a damn about how other people might react to his commentaries. That’s nice.

In any case, if anyone was still in denial, R1b-M269 expanded with Yamna (through the Bell Beaker expansion) into Iberia, hence yes, 90% of modern Basque male lineages have an origin in the steppe, like the R1b-DF27 sample recently found, and their common ancestor spoke Late Proto-Indo-European.

Findings like these, which should be taken as normal developments of research, are apparently still a trauma for many – like R1a-fans from India realizing most of their paternal ancestors came from the steppe, or its fans from Northern Europe understanding that their paternal ancestors probably spoke Uralic or a related language; or N1c-fans seeing how their paternal ancestors probably didn’t speak Uralic. It seems life isn’t fair to stupid simplistic ethnolinguistic ideas

Let’s see which Y-DNA haplogroups we find in West Yamna, to verify the latest migration model of Late PIE speakers of the Reich Lab (featured image).

Check out also the BBC News coverage of David Reich and Nick Patterson, the two most influential researchers of the moment in Human Ancestry: How ancient DNA is transforming our view of the past.

Related:

The uneasy relationship between Archaeology and Ancient Genomics

Allentoft Corded Ware

News feature Divided by DNA: The uneasy relationship between archaeology and ancient genomics, Two fields in the midst of a technological revolution are struggling to reconcile their views of the past, by Ewen Callaway, Nature (2018) 555:573-576.

Interesting excerpts (emphasis mine):

In duelling 2015 Nature papers6,7the teams arrived at broadly similar conclusions: an influx of herders from the grassland steppes of present-day Russia and Ukraine — linked to Yamnaya cultural artefacts and practices such as pit burial mounds — had replaced much of the gene pool of central and Western Europe around 4,500–5,000 years ago. This was coincident with the disappearance of Neolithic pottery, burial styles and other cultural expressions and the emergence of Corded Ware cultural artefacts, which are distributed throughout northern and central Europe. “These results were a shock to the archaeological community,” Kristiansen says.

(…)

Still, not everyone was satisfied. In an essay8 titled ‘Kossinna’s Smile’, archaeologist Volker Heyd at the University of Bristol, UK, disagreed, not with the conclusion that people moved west from the steppe, but with how their genetic signatures were conflated with complex cultural expressions. Corded Ware and Yamnaya burials are more different than they are similar, and there is evidence of cultural exchange, at least, between the Russian steppe and regions west that predate Yamnaya culture, he says. None of these facts negates the conclusions of the genetics papers, but they underscore the insufficiency of the articles in addressing the questions that archaeologists are interested in, he argued. “While I have no doubt they are basically right, it is the complexity of the past that is not reflected,” Heyd wrote, before issuing a call to arms. “Instead of letting geneticists determine the agenda and set the message, we should teach them about complexity in past human actions.”

Many archaeologists are also trying to understand and engage with the inconvenient findings from genetics. (…)
[Carlin:] “I would characterize a lot of these papers as ‘map and describe’. They’re looking at the movement of genetic signatures, but in terms of how or why that’s happening, those things aren’t being explored,” says Carlin, who is no longer disturbed by the disconnect. “I am increasingly reconciling myself to the view that archaeology and ancient DNA are telling different stories.” The changes in cultural and social practices that he studies might coincide with the population shifts that Reich and his team are uncovering, but they don’t necessarily have to. And such biological insights will never fully explain the human experiences captured in the archaeological record.

Reich agrees that his field is in a “map-making phase”, and that genetics is only sketching out the rough contours of the past. Sweeping conclusions, such as those put forth in the 2015 steppe migration papers, will give way to regionally focused studies with more subtlety.

This is already starting to happen. Although the Bell Beaker study found a profound shift in the genetic make-up of Britain, it rejected the notion that the cultural phenomenon was associated with a single population. In Iberia, individuals buried with Bell Beaker goods were closely related to earlier local populations and shared little ancestry with Beaker-associated individuals from northern Europe (who were related to steppe groups such as the Yamnaya). The pots did the moving, not the people.

This final paragraph apparently sums up a view that Reich has of this field, since he repeats it:

Reich concedes that his field hasn’t always handled the past with the nuance or accuracy that archaeologists and historians would like. But he hopes they will eventually be swayed by the insights his field can bring. “We’re barbarians coming late to the study of the human past,” Reich says. “But it’s dangerous to ignore barbarians.”

I would say that the true barbarians didn’t have a habit or possibility to learn from the higher civilizations they attacked or invaded. Geneticists, on the other hand, only have to do what they expect archaeologists to do: study.

EDIT (30 MAR 2018): A new interesting editorial of Nature, On the use and abuse of ancient DNA.

See also:

David Reich on the influence of ancient DNA on Archaeology and Linguistics

An interesting interview has appeared on The Atlantic, Ancient DNA Is Rewriting Human (and Neanderthal) History, on the occasion of the publication of David Reich’s book Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past.

Some interesting excerpts (I have emphasized some of Reich’s words):

On the efficiency of the Reich Lab

Zhang: How much does it cost to process an ancient DNA sample right now?

Reich: In our hands, a successful sample costs less than $200. That’s only two or three times more than processing them on a present-day person. And maybe about one-third to one half of the samples we screen are successful at this point.

This is probably the most controversial assessment for the Twitterverse, since it puts the Reich Lab at the top of the publishing chain, but I don’t find this fact controversial; at all.

Anyone interested in doing genetic studies has free datasets, papers, and bioinformatic tools at hand – thanks to his lab, mostly – to develop new methods and publish papers. Such secondary works won’t probably be published in journals with the highest impact factor, but what can you do, welcome to the scientific world…

Also, by the looks of it, every single researcher involved in recovering an archaeological sample is included as co-author of the papers, so there is a clear benefit for ‘local’ researchers collaborating with the Lab. Therefore, these researchers and their institutions are responsible for whatever unfair situation might be created by their exchange.

On Archaeology’s reaction to Kossinna and Nazi ideas:

(…)
Zhang: You actually had German collaborators drop out of a study because of these exact concerns, right? One of them wrote, “We must(!) avoid … being compared with the so-called ‘siedlungsarchäologie Method’ from Gustaf Kossinna!”

Reich: Yeah, that’s right. I think one of the things the ancient DNA is showing is actually the Corded Ware culture does correspond coherently to a group of people. I think that was a very sensitive issue to some of our coauthors, and one of the coauthors resigned because he felt we were returning to that idea of migration in archaeology that pots are the same as people. There have been a fair number of other coauthors from different parts of continental Europe who shared this anxiety.

We responded to this by adding a lot of content to our papers to discuss these issues and contextualize them. Our results are actually almost diametrically opposite from what Kossina thought because these Corded Ware people come from the East, a place that Kossina would have despised as a source for them. But nevertheless it is true that there’s big population movements, and so I think what the DNA is doing is it’s forcing the hand of this discussion in archaeology, showing that in fact, major movements of people do occur. They are sometimes sharp and dramatic, and they involve large-scale population replacements over a relatively short period of time. We now can see that for the first time.

What the genetics is finding is often outside the range of what the archaeologists are discussing these days.

This is mostly true: Genomics offers a whole new dimension to assess exchanges among groups, and help thus select anthropological models of cultural diffusion. They offer another way of interpreting prehistoric cultural evolution and change, including the investigation of potential languages of these cultures, ways of change and replacement, etc.

Also, he acknowledges that there is a lot of content added to the papers in search for context – and thus avoid simplistic assumptions and conclusions – , so this is a reasonable way to look at the (often erroneous) cultural and linguistic context which accompany most genetic papers, and even the new methods being developed to assess samples.

On the other hand, the fact that many in Archaeology didn’t want to discuss migrations does not mean that it was not discussed at all, as he seems to suggest.

On how Genomics fits with traditional disciplines

Zhang: I think at one point in your book you actually describe ancient DNA researchers as the “barbarians” at the gates of the study of history.

Reich: Yeah.

Zhang: Does it feel that way? Have you gotten into arguments with archaeologists over your findings?

Reich: I think archaeologists and linguists find it frustrating that we’re not trained in the language of archaeology and all these sensitivities like about Kossinna. Yet we have this really powerful tool which is this way of looking at things nobody has been able to look at before.

The point I was trying to make there was that even if we’re not always able to articulate the context of our findings very well, this is very new information, and a serious scholar really needs to take this on board. It’s dangerous. Barbarians may not talk in an educated and learned way but they have access to weapons and ways of looking at things that other people haven’t looked to. And time and again we’ve learned in the past that ignoring barbarians is a dangerous thing to do.

I think this is also mostly true: many academics find it frustrating to read these papers, most of which lack a minimal understanding of the topics being discussed.

For example, you can’t pretend to derive meaningful conclusions about Proto-Indo-Europeans knowing nothing about their language and the potential cultures associated with them (and why they were associated with them in the first place)…

I also agree with him in that the study of ancient DNA is a very powerful tool. Everyone involved in Anthropology and Archaeology should be trained these days in Genomics – or, at least, they should have the opportunity to do so.

On the dangers of Genomics

Reich: (…) I know there are extremists who are interested in genealogy and genetics. But I think those are very marginal people, and there’s, of course, a concern they may impinge on the mainstream.

But if you actually take any serious look at this data, it just confounds every stereotype. It’s revealing that the differences among populations we see today are actually only a few thousand years old at most and that everybody is mixed. I think that if you pay any attention to this world, and have any degree of seriousness, then you can’t come out feeling affirmed in the racist view of the world. You have to be more open to immigration. You have to be more open to the mixing of different peoples. That’s your own history.

I guess David Reich does not frequent forums on human genetics linked to ethnolinguistic identification, or he would not think of ‘extremists’ as marginal people. Or else we have a different view of what defines an ‘extremist’…

Conclusion

I did not have the best of opinions about David Reich – or any other geneticist involved in publishing anthropological theories, for that matter. I have always had great respect for their scientific work, though.

If anything, this article shows that he knows his own (and his fellow geneticists’) limitations, and the dangers and limitations of Genomics as a whole, so I have more respect for him – and anyone involved with his Lab’s work – after reading this piece.

I would sum up his interview with his humbling sentence:

We should think we really don’t know what we’re talking about.

NOTE. Also on the occasion of the publication of his book, Nature has published the piece Sex, power and ancient DNA – Turi King hails David Reich’s thrilling account of mapping humans through time and place.

After buying Lalueza-Fox’s recent book ‘La forja genètica d’Europa’, I don’t really feel like buying another book on Genomics and migrations from a geneticist. If you have read Reich’s book, please share your impressions.

EDIT (19 MAR 2018): Razib Khan has written a ‘preview of a review‘ that he intends to publish on the National Review, and it seems the book might be worth it, after all.

EDIT (20 MAR 2018): The New York Times’ Carl Zimmer writes a review, David Reich Unearths Human History Etched in Bone. Seen first in Razib Khan’s Gene Expression blog.