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Friday, June 28, 2019

On the origin of the Gravettians (Bennett et al. 2019 preprint)


Over at bioRxiv at this LINK. No major surprises, as far as I can see. From the preprint, emphasis is mine:

The Gravettian technocomplex was present in Europe from more than 30,000 years ago until the Last Glacial Maximum, but the source of this industry and the people who manufactured it remain unsettled. We use genome-wide analysis of a ~36,000-year-old Eastern European individual (BuranKaya3A) from Buran-Kaya III in Crimea, the earliest documented occurrence of the Gravettian, to investigate relationships between population structures of Upper Palaeolithic Europe and the origin and spread of the culture. We show BuranKaya3A to be genetically close to both contemporary occupants of the Eastern European plain and the producers of the classical Gravettian of Central Europe 6,000 years later. These results support an Eastern European origin of an Early Gravettian industry practiced by members of a distinct population, who contributed ancestry to individuals from much later Gravettian sites to the west.

...

The mitochondrial haplogroup of BuranKaya3A was determined to belong to an early branch of the N lineage, N1.

...

In addition, the N1 of BuranKaya3A carries three of the eight mutations occurring prior to N1b, a rare haplogroup most highly concentrated in the Near East, yet appearing broadly from western Eurasia to Africa. The descendants of the N1b node include N1b2, currently found only in Somalia [22], and N1b1b, found in nearly 10% of Ashkenazi Jewish haplogroups [23]. These three mutations allow us to place BuranKaya3A on a lineage apart from that which has been proposed to later enter Europe from Anatolia during the Neolithic (N1a1a) [24]. Among ancient samples, the mitochondrial sequence of an 11,000-year-old Epipalaeolithic Natufian from the Levant (“Natufian9”) [25] is also a later derivative of this N1b branch.

...

From the reads mapping to the Y chromosome, six out of six Single Nucleotide Polymorphisms (SNPs) that overlap with diagnostic sites for Y-haplogroup BT all carry the derived allele, allowing a minimum assignment to BT, which has origins in Africa, with additional derived alleles suggesting an eventual placement of CT or C, found in Asia and the Epipalaeolithic Near East [25]. Additional ancestral alleles make an assignment of C1a2 or C1b, which appear in UP Europe [1], unlikely (see Table S3 for a summary and comparative placement of Palaeolithic Y-haplogroups, and Supplementary Data 1 for a complete list of Y diagnostic SNPs).


Bennett et al., The origin of the Gravettians: genomic evidence from a 36,000-year-old Eastern European, bioRxiv, posted June 28, 2019, doi: https://doi.org/10.1101/685404

Monday, June 24, 2019

Genetic substructures and adaptations in Lithuanians (Urnikyte et al. 2019)


Over at Scientific Reports at this LINK. Apparently, the genotype data from this paper will be available at figshare in just over three months (see here). Among other things, the paper makes some interesting points about the relationship between the genetic ancestry of Lithuanians and their language:

Partial genetic isolation of the Lithuanians is a possible explanation for the structure results observed. Until the late Middle Ages, the eastern Baltic region was one of the most isolated corners of Europe [27]. Moreover, after the fall of the Roman Empire in the 5th century, the eastern Baltic region was spared by the subsequent population movements of the Migration Period [26,28], which allowed the most archaic of all the living speaking Indo-European languages [1] to survive. Thus, Lithuanians could retain their cultural identity.

Urnikyte et al., Patterns of genetic structure and adaptive positive selection in the Lithuanian population from high-density SNP data, Scientific Reports volume 9, Article number: 9163 (2019), DOI: https://doi.org/10.1038/s41598-019-45746-3

See also...

Fresh off the sledge

Uralic-specific genome-wide ancestry did make a signifcant impact in the East Baltic

It was always going to be this way

Inferring the linguistic affinity of long dead and non-literate peoples: a multidisciplinary approach

Saturday, June 15, 2019

Not Bell Beaker, not Corded Ware, but...the SGBR complex


I'd be very grateful if someone could explain to me what this new paper at the Proceedings of the Prehistoric Society journal was actually about.

Citation...

Furholt, Martin, Re-integrating Archaeology: A Contribution to aDNA Studies and the Migration Discourse on the 3rd Millennium BC in Europe, Proceedings of the Prehistoric Society, Published online: 10 June 2019, DOI: https://doi.org/10.1017/ppr.2019.4

See also...


Sunday, June 9, 2019

Genetic continuity across the millennia in central Poland


Apparently, ancient DNA and anthropological research on the populations of what is now central Poland suggests strong genetic continuity in the region since the Neolithic or even Mesolithic. Science in Poland has a news feature about the soon to be published study (see here). Below are a few quotes from the article. Emphasis is mine:

How were the people in Poland changing over the centuries, from the early Middle Ages to the 19th century? Did the Slavs migrate to our territories, or are they indigenous? The 3D scanning project and digital access to skulls, skeletons and DNA from human remains from central Poland is expected to help answer these questions.

...

Research shows that the shape of the cerebral part of the skull has changed over the centuries - people in the early Middle Ages had more elongated heads. This interesting phenomenon has not been fully explained yet. "There are many theories on this subject, but it is not known whether this was a microevolutionary genetic change, or perhaps an environmentally conditioned one, associated with a reconstruction of the skull as a consequence of the chewing apparatus being relieved" - he adds.

Researchers are also trying to assess the level of diversity of the population living in the territory of present-day Poland during that period and whether migrants from other areas of Europe, for example from Scandinavia, appeared here. "There is the topic of participation of Scandinavian groups in the creation of the Polish State. Such groups indeed penetrated Poland, they could be hired warriors. But I think that, for example, we can probably put aside the hypothesis that Mieszko I was Scandinavian" - the researcher says.

The features, the variability of which anthropologists study, include the height of the body. We already know that, for example, people in the early Middle Ages in Poland were relatively tall, similar to Poles in the 1960s. Later there was a clear decline in body height, lasting until the 19th century.

...

There are already first conclusions from the research of the team from the Biobank Laboratory and the Department of Anthropology. The researchers believe that in the case of the population living in Kujawy there was a surprisingly strong genetic continuity, dating back to the time of the first farmers, 7.5 thousand years ago.

"It seems that we are dealing with an interesting genetic continuation in the population living in Kujawy from the early Middle Ages to the 19th century. The roots of these populations probably reach the Neolithic, perhaps even the Mesolithic" - the scientist suggests.

Source: 3D scans of skulls and a collection of ancient DNA will be available on the information platform e-Czlowiek.pl

See also...

They came, they saw, and they mixed

Saturday, June 1, 2019

They came, they saw, and they mixed


Y-chromosome haplogroup N is strongly associated with Uralic-speaking populations. That's probably because it was a salient feature of the gene pool of the earliest Uralic speakers, and it went with them as they migrated across northern Eurasia. However, some of its younger subclades appear to have spread with the speakers of Indo-European and Turkic languages.

For instance, N-Y10931 seems to be a marker of the Rurikids, a Varangian dynasty that, according to most sources, ruled the Kievan Rus in what are now Russia and Ukraine. And the Kievan Rus was a lose medieval political federation in which Slavic, Finnic (west Uralic) and Germanic languages were probably spoken. The latest on the genetic genealogy of the Rurikids was presented a couple of days ago at the Centenary of Human Population Genetics conference in Moscow, and there's an abstract of the talk available here (download the PDF and scroll down to page 84).

I'm not aware of any Rurikids among the thousands of ancients in my dataset, or even of any samples belonging to N-Y10931. But I do have the genome of someone who belongs to N-Y4339, which, as per the abstract linked to above, is proximally ancestral to N-Y10931. Not only does this person come from Viking Age Scandinavia, but he was buried in a crouched position typical of Slavic funerary customs of the time.

The individual in question is vik_84001. His genome was published recently along with a paper on the population structure of the Swedish town of Sigtuna way back when it was a Viking stronghold (see here). This is where his Y-chromosome sequence, labeled ERS2540883, is positioned on the YFull Y-chromosome phylogenetic tree. Click on the image to go to YFull.


However, the result is likely to be compromised to some extent by missing data. If so, it's possible that vik_84001 does indeed belong to N-Y10931 and ought to be sitting near or even among that cluster of Russian samples (Rurik descendants?) at the bottom of the page.

In any case, vik_84001 seems to be the closest individual in the ancient DNA record to a Rurikid. The Principal Component Analysis (PCA) below is based on my Global25 data. It features 18 other Viking Age individuals from Sigtuna alongside vik_84001 (look for the black dots). The relevant datasheet is available here. Interestingly, despite his eastern Y-haplogroup, vik_84001 is one of the few Sigtuna ancients who clusters strongly with present-day Swedes.
But here's what happens when I model his ancestry proportions with the Global25/nMonte method using a wide range of reference populations from Northern and Eastern Europe. The Swedes in this model are the same as those in the PCA.

vik_84001
Swedish,84.6
Ingrian,9.2
Russian_Tver,6.2

Belarusian,0
Estonian,0
Finnish,0
Finnish_East,0
Karelian,0
Latvian,0
Mordovian,0
Russian_Kostroma,0
Russian_Kursk,0
Russian_Orel,0
Russian_Pinega,0
Russian_Smolensk,0
Russian_Voronez,0
Ukrainian,0
Vepsian,0

[1] "distance%=2.3778"

Yep, despite his position in the PCA, vik_84001 shows a strong signal of ancestry related to the present-day populations of northwestern Russia. I'm not sure what this means exactly, but it's certainly fascinating stuff. And, by the way, I usually wouldn't use so many similar reference populations in a single Global25/nMonte model because of the problem of "overfitting", but in some cases it's OK to do so if the nMonte algorithm has enough recent genetic drift to latch onto.

See also...

More on the association between Uralic expansions and Y-haplogroup N

Fresh off the sledge

Uralic-specific genome-wide ancestry did make a signifcant impact in the East Baltic

It was always going to be this way

Conan the Barbarian probably belonged to Y-haplogroup R1a