August 15, 2014

mtDNA from Chalcolithic Iberia (El Mirador cave)

A very exciting new study from Chalcolithic Iberia. The authors compare their mtDNA data with those from the Brandt et al. (2013) paper which includes German samples from the same time.

The following plot seems quite useful. From its caption:
This study: El Mirador (MIR). Published prehistoric cultures [21]: Hunter-gatherer central (HGC), Linear Pottery culture (LBK), Rössen culture (RSC), Schöningen group (SCG), Baalberge culture (BAC), Salzmünde culture (SMC), Bernburg culture (BEC), Corded Ware culture (CWC), Bell Beaker culture (BBC), Unetice culture (UC), Funnel Beaker culture (FBC), Pitted Ware culture (PWC), Hunter-Gatherer south (HGS), (Epi) Cardial (CAR), Neolithic Portugal (NPO), Neolithic Basque Country and Navarre (NBQ), Treilles culture (TRE), Hunter-gatherer east (HGE), Bronze Age Siberia (BAS), Bronze Age Kazakhstan (BAK).

From the paper:
In none of the analyses El Mirador sample shows close genetic affinities with a contemporaneous Bell Beaker population of 29 specimens gathered from three sites in Germany. The Bell Beaker mtDNA signal is characterized by high frequencies (around 50%) of H haplogroup that in El Mirador only reaches 26%. This heterogeneity in the genetic composition of geographically close populations adds further complexity to future reconstructions of these ancient expansions and correlates with the existence of contemporaneous groups with and without the typical Bell Beaker burial kit.
mtDNA may not be the best tool for studying the spread of Bell Beakers (if this involved men), but this shows that the high frequency of H in Bell Beakers of Germany (observed by Brandt et al.) is not due to an even higher frequency of H in Iberia.

PLoS ONE 9(8): e105105. doi:10.1371/journal.pone.0105105

Mitochondrial DNA from El Mirador Cave (Atapuerca, Spain) Reveals the Heterogeneity of Chalcolithic Populations

Daniel Gómez-Sánchez,Iñigo Olalde et al.

Previous mitochondrial DNA analyses on ancient European remains have suggested that the current distribution of haplogroup H was modeled by the expansion of the Bell Beaker culture (ca 4,500–4,050 years BP) out of Iberia during the Chalcolithic period. However, little is known on the genetic composition of contemporaneous Iberian populations that do not carry the archaeological tool kit defining this culture. Here we have retrieved mitochondrial DNA (mtDNA) sequences from 19 individuals from a Chalcolithic sample from El Mirador cave in Spain, dated to 4,760–4,200 years BP and we have analyzed the haplogroup composition in the context of modern and ancient populations. Regarding extant African, Asian and European populations, El Mirador shows affinities with Near Eastern groups. In different analyses with other ancient samples, El Mirador clusters with Middle and Late Neolithic populations from Germany, belonging to the Rössen, the Salzmünde and the Baalberge archaeological cultures but not with contemporaneous Bell Beakers. Our analyses support the existence of a common genetic signal between Western and Central Europe during the Middle and Late Neolithic and points to a heterogeneous genetic landscape among Chalcolithic groups.



bellbeakerblogger said...

So by CRS would I be correct to assume that it is H2a2a?

If so, any thoughts on the conspicuously absent low H's, particularly H1 & H3 which were supposedly hunkered down in Iberia in the Ice Age?

Do the mtdna's in Mirador appear ridicuously North Middle Eastern, or is that a stretch?

Kes said...

The obvious answer: the key here is the data for NPO - Neolithic Portugal, with the highest frequency of H. It has long been hypothesized that BB started in Portugal and first spread by sea (to Brittany, Britain and the North Sea), bypassing much of central Iberia and southern France at first. So this study actually supports one of the most widespread accounts for the spread of BB.

Dr Rob said...
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George said...
Questions about Bronze Age Kazakhstan (BAK).
100% west Eurasian mtdna (and mostly south European mtdna) in Kazakhstan Bronze age?
Which exactly culture is BAK (Bronze Age Kazakhstan)?
And from where? From West Kazakhstan? From Central Kazakhstan?

The Altay Bronze Age had only 40% west Eurasian mtdna.

Also the BAK (Bronze Age Kazakhstan) mtdna is very close to Rostov Scythian mtdna

Davidski said...

"mtDNA may not be the best tool for studying the spread of Bell Beakers (if this involved men), but this shows that the high frequency of H in Bell Beakers of Germany (observed by Brandt et al.) is not due to an even higher frequency of H in Iberia."

This comment ignores the fact that the sample from Chalcolithic Portugal has a higher frequency of H than the Bell Beakers from Central Europe.

And where are Bell Beakers supposed to have come from? I keep reading that its Portugal not Spain.

Davidski said...

Dr Rob,

Totally serious question here. Do you actually read the papers you comment on here, or do you just, like, use the force and hope for the best?

Kurti said...

@George Bronze Age Kazakhstan is Indo_Iranian.

Simon_W said...

Regarding Bell Beakers and H, I fully agree with Kes and Davidski.

But now for some observations on the haplogroups termed „Late Neolithic / Early Bronze Age“ in Brandt, Haak et al. 2013:

U2 is present in eastern hunter-gatherers, in Bronze Age Siberia, in Corded people and in Unetice. It's seems connected with the y-DNA R1a complex, it's definitely a legacy of eastern European hunter-gatherers, and it's completely absent in Bell Beaker people.

I is present in Bronze Age Kazakhstan, in Corded people, in Unetice, and very surprisingly also in the Neolithic Basque country. But nowhere else.

T1 is present in Bronze Age Kazakhstan, in Bronze Age Siberia, in Corded people and in Unetice, thus it's present in the y-DNA R1a complex, but it's also present in Baalberge and in German Bell Beakers. This might be the „Indo-European marker“! It arrived sufficiently late and it spread far and wide. Perhaps it was accompanied by y-DNA J2.

Some observations on haplogroup H:
It's most common in Neolithic Portugal, where it makes up a large majority of the mt-DNAs.
On the second place follow the Bell Beaker people.
Third are the Neolithic Basques.

Neolithic Portugal looks very peculiar: lots of H, followed by some U5a and U5b, and last a little V.
The only haplogroup here that is exclusively early farmer, is V. And V wasn't present in the Cardium people! It was present in the LBK. I would surmise this means that the Neolithic in Portugal was started by people who came from the eastern Mediterranean, but who were not descended from the early Cardium wave. Maybe these were accompanied by y-DNA R1b?! And later R1b spread to central Europe with the Bell Beaker wave from Portugal? (Note that it's very dubious that Neolithic Portugal was Indo-European speaking. Possibly their language was ancestral to Tartessian, which is currently regarded as unclassified and presumably non-IE.)

In the PCA with modern populations, El Mirador looks closest to Druze. Thus Chalcolithic Mirador probably represents another influx from Western Asia, but it didn't carry haplogroup T1. Which might mean that these were not Indo-Europeans.

Finally some observations on the PCA with the ancient samples:

It's striking how different LBK and Cardium were! This is in line with Eva Fernandez et al. 2014.
The southern and the central hunter-gatherers are relatively close to each other, they occupy another corner of the plot.
The eastern complex is clearly discernible in the lower right quarter of the plot, with eastern hunter-gatherers, Pitted Ware, Bronze Age Siberia and Kazakhstan and Unetice. The Corded people diverge slightly into this direction.
LBK and Rössen are very close to each other, no surprise.
And from LBK & Rössen there is a cline towards the central hunter-gatherers. The later Neolithic cultures from Germany diverge on this cline towards the central hunter-gatherers, first Baalberge, then Funnelbeaker, then Bernburg. Surprisingly Treilles in southern France is also on this cline, far from the Cardium people and close to Baalberge and Funnelbeaker. I suppose this means that central European farmers migrated southwards too.
El Mirador is neither close to LBK nor to Cardium people, and it occupies the middle of the left fringe of the plot. Well, we know they were similar to modern Near Easterners. Close to them are also Salzmünde and the Schöningen group. I think Schöningen was some late form of Lengyel which might explain some additional, later Near Eastern input via southeastern Europe.
The position of Neolithic Portugal in the plot is puzzling, but not surprising, given their peculiar haplogroup composition.
The German Bell Beakers are close to Neolithic Portugal. From the plot it's not clear wether this is because of Portuguese admixture or because it's simply a further step on the cline towards central hunter-gatherers. But given their high incidence of haplogroup H, it's clear that admixture mattered.

Dr Rob said...
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Dr Rob said...
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Simon_W said...

Dr Rob, an expansion from coastal Portugal isn't at odds with more complex scenarios. The Bell Beaker package originated there, spread to other parts of Europe, got modified and complemented with other elements, and then various groups moved into various directions:

Unknown said...

Well, that does it. My vote for the signature gene of (western) Indo-European is now mtDNA H.

Linguists are fond of defining “natural language” as the one that you learn “on your mother’s knee.”

My new guess is mothers spread the Indo-European languages in Europe and that mothers carrying H were the main perpetrators.

In the oldest written epic, Gilgamesh sends a temple priestess out to sleep with Enkidu, the wild man. After that, Enkidu can no longer speak to the wild animals or understand them. Women. The door to civilization.

I suspect those H ladies (and maybe those T2s,too) were at Varna and I think they in fact dominate at Cucuteni-Trypillian, which is not on this list.

Diversity is plainly evident with all these mtDNA haplogroups in Europe at the time. But the thread is plainly H.

With regard to the oddness of the Bell Beaker culture, see Janusz Czebreszuk, ed., Similar but Different: Bell Beakers in Europe (2013), who is also cited in this report on El Mirador.

Bell Beaker seems to spread as outposts, very similar to the Mycenaean enclaves in the western Mediterranean and the attested Assyrian outposts in Anatolia. And like some such outposts, they started to acquire their own identities. What were they outposts for? I think they were retail outlets for copper out of Iberia, even though we don’t find much of it in the early Bell Beaker expansion. I think that is because the limited supply does not show up in the digs on early sites.

This impetus towards consumerism (see Sherratt) showed up in Iberia out of the Balkans, of course. At the same time, it was also taking the short trip to Anatolia and the Caucasus.

Just in case any Kurgan-Steppes advocate mistakes what this paper is saying about IE origins, it gives a nod of support to the idea that Bell Beaker might have picked up the language of Corded Ware in Central Europe and brought it back to the homeland in Iberia.

The paper cites Patterson, et al. (2012) “Ancient Admixture in Human History:”
“They interpret this signal as the result of a reverse migration from central Europe into Iberia after an initial Bell Beaker culture expansion from Iberia. This has been previously hypothesized from archaeological data [37] but so far has not been observed with ancient genetic data due to the current lack of genetic information from Iberian Bell Beaker groups.”

Of course, both Patterson and the cited archaeological paper say something slightly different.

Patterson in fact is quite non-committal about the steppes theory implication:
“An alternative history that could produce the signal of Asian-related admixture in northern Europeans is admixture from steppe herders speaking Indo-European languages...(Anthony 2007). However, this hypothesis cannot explain the ancient DNA result that northern Europeans today appear admixed between populations related to Neolithic and Mesolithic Europeans (Skoglund et al. 2012), and so even if the steppe hypothesis has some truth, it can explain only part of the data.”

Davidski said...

Yes, but the Bell Beaker sample clusters with the Neolithic Portuguese sample in the PCA from this study.

So claiming that this study doesn't support a Bell Beaker origin in Portugal is dumb.

Dr Rob said...
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Grey said...

If there were two farmer waves

(yes over simplifying but anyway)

then two of the possible ways it could have occurred are:

1) first wave expands along both the med and the atlantic and a conquering second wave displaces the first wave without much of a trace along the med coast but doesn't reach the atlantic coast so the first wave survives there.

2) first wave expands along the med coast but not the atlantic (or only in very low population density) and the second wave don't have the strength to displace the first wave along the med because all the best settlement sites are already taken so instead they hop over the first wave (with maybe a few stepping stone settlements along the way) until they reach the less populated atlantic coast where they become dominant.

Roy said...

"agenda driven commentators who scurry to philosophise"?
yea, those tend to use phrases like "reductionist, post-hoc analysis" rather than dirty their hands with the details, because its 'too early' or 'too complex' to give a nuanced opinion.

Dr Rob said...
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Grognard said...

@rob - I find it funny you won't even admit for sure that BB spread eastward from portugal. This has always been the most plausible through explanation, that is not really that disputed any more. In light of this info, there can't really be any doubt of that.

There's also not that much doubt bell beaker was r1b, the question is really only whether or not r1b was already a big part of europe before bell beaker came about.

This paper strongly implies that the genetics of europe were already largely in place before bell beaker time, not that it spread r1b. Which is a theory that has many holes.

The new haak et. al paper is taken by most to mean step theory is correct, but like this paper the obvious implication is that genetics of europe were largely in place even back in eneolithic, if perhaps in different proportions.

Of course you'll never find atlantic or megalithic r1b if you are not even looking, but it beggars belief that H spread east while r1b spread west and they initially had no relation to each other. Especially with finds of r1b all the way from russia to iberia now.