The previous post showed the potential use of TreeToM to visualize ancient DNA samples in maps together with their Y-DNA phylogenetic trees. I have written Newick trees for Y-chromosome haplogroups R1b-L388 (encompassing R-V1636 and R-P297, which in turn split into R-M73 and R-M269), R1a, and N.
I have reviewed some of the BAM files from my previous bulk analyses with YLeaf v.2, to add information that I had not previously included in the All Ancient DNA Dataset, and which might be relevant to the proper depiction of phylogenetic trees; in particular, positive and negative SNPs potentially distinguishing archaic… Read the rest “Ancient phylogeography: spread of haplogroups R1b, R1a and N”
Now that it has become evident that Late Repin (i.e. Yamnaya/Afanasevo) ancestry was associated with the migration of R1b-L23-rich Late Proto-Indo-Europeans from the steppe in the second half of the the 4th millennium BC, there’s still the question of how R1a-rich Uralic speakers of Corded Ware ancestry expanded , and how they spread their languages throughout North Eurasia.
Modern North Eurasians
I have been collecting information from the supplementary data of the latest papers on modern and ancient North Eurasian peoples, including Jeong et al. (2019), Saag et al. (2019), Sikora et al. (2018), or … Read the rest “Corded Ware ancestry in North Eurasia and the Uralic expansion”
Open access Population genomics of the Viking world, by Margaryan et al. bioRxiv (2019), with a huge new sampling from the Viking Age.
Interesting excerpts (emphasis mine, modified for clarity):
To understand the genetic structure and influence of the Viking expansion, we sequenced the genomes of 442 ancient humans from across Europe and Greenland ranging from the Bronze Age (c. 2400 BC) to the early Modern period (c. 1600 CE), with particular emphasis on the Viking Age. We find that the period preceding the Viking Age was accompanied by foreign gene flow into Scandinavia from the south and east:
… Read the rest “Vikings, Vikings, Vikings! “eastern” ancestry in the whole Baltic Iron Age”
The recent study of Estonian Late Bronze Age/Iron Age samples has shown, as expected, large genetic continuity of Corded Ware populations in the East Baltic area, where West Uralic is known to have been spoken since at least the Early Bronze Age.
The most interesting news was that, unexpectedly for many, the impact of “Siberian ancestry” (whatever that actually means) was small, slow, and gradual, with slight increases found up to the Middle Ages, compatible with multiple contact events in north-eastern Europe. Haplogroup N became prevalent among Finnic populations only through late bottlenecks, as research of modern … Read the rest “Genetic continuity among Uralic-speaking cultures in north-eastern Europe”
Good timing for the publication of two interesting papers, that a lot of people should read very carefully:
Open access A tutorial on how not to over-interpret STRUCTURE and ADMIXTURE bar plots, by Daniel J. Lawson, Lucy van Dorp & Daniel Falush, Nature Communications (2018).
Interesting excerpts (emphasis mine):
Experienced researchers, particularly those interested in population structure and historical inference, typically present STRUCTURE results alongside other methods that make different modelling assumptions. These include TreeMix, ADMIXTUREGRAPH, fineSTRUCTURE, GLOBETROTTER, f3 and D statistics, amongst many others. These models can be used both to probe whether assumptions of the model
… Read the rest “Common pitfalls in human genomics and bioinformatics: ADMIXTURE, PCA, and the ‘Yamnaya’ ancestral component”
In my recent post about the origin and expansion of haplogroup R1b-L51, Chetan made an interesting comment on the origin and expansion of R1a-Z645. Since this haplogroup is also relevant for European history and dialectal North-West Indo-European and Indo-Iranian expansion, I feel compelled to do a similar post, although the picture right now is more blurry than that of R1b-L51.
I find it interesting that many geneticists would question the simplistic approach to the Out of Africa model as it is often enunciated, but they would at the same time consider the current simplistic model of Yamna expansion… Read the rest “On the origin and spread of haplogroup R1a-Z645 from eastern Europe”
Chapter The Sea and Bronze Age Transformations, by Christopher Prescott, Anette Sand-Eriksen, and Knut Ivar Austvoll, In: Water and Power in Past Societies (2018), Emily Holt, Proceedings of the IEMA Postdoctoral Visiting Scholar Conference on Theories and Methods in Archaeology, Vol. 6.
NOTE. You can download the chapter draft at Academia.edu.
Abstract (emphasis mine):
Along the western Norwegian coast, in the northwestern region of the Nordic Late Neolithic and Bronze Age (2350–500 BCE) there is cultural homogeneity but variable expressions of political hierarchy. Although new ideological institutions, technology (e.g., metallurgy and boat building), intensified agro‑pastoral farming, and
… Read the rest “Minimal Corded Ware culture impact in Scandinavia – Bell Beakers the unifying maritime elite”
New paper (behind paywall), Ancient genomes from Iceland reveal the making of a human population, by Ebenesersdóttir et al. Science (2018) 360(6392):1028-1032.
Abstract and relevant excerpts (emphasis mine):
Opportunities to directly study the founding of a human population and its subsequent evolutionary history are rare. Using genome sequence data from 27 ancient Icelanders, we demonstrate that they are a combination of Norse, Gaelic, and admixed individuals. We further show that these ancient Icelanders are markedly more similar to their source populations in Scandinavia and the British-Irish Isles than to contemporary Icelanders, who have been shaped by 1100 years of
… Read the rest “Reproductive success among ancient Icelanders stratified by ancestry”