Ancient phylogeography: spread of haplogroups R1b, R1a and N

haplogroups-r1a-r1b-q

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 archaicRead the rest “Ancient phylogeography: spread of haplogroups R1b, R1a and N”

Vikings, Vikings, Vikings! “eastern” ancestry in the whole Baltic Iron Age

vikings-middle-age

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:

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A very “Yamnaya-like” East Bell Beaker from France, probably R1b-L151

bell-beaker-expansion

Interesting report by Bernard Sécher on Anthrogenica, about the Ph.D. thesis of Samantha Brunel from Institut Jacques Monod, Paris, Paléogénomique des dynamiques des populations humaines sur le territoire Français entre 7000 et 2000 (2018).

NOTE. You can visit Bernard Sécher’s blog on genetic genealogy.

A summary from user Jool, who was there, translated into English by Sécher (slight changes to translation, and emphasis mine):

They have a good hundred samples from the North, Alsace and the Mediterranean coast, from the Mesolithic to the Iron Age.

There is no major surprise compared to the rest of Europe. On the PCA

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Common pitfalls in human genomics and bioinformatics: ADMIXTURE, PCA, and the ‘Yamnaya’ ancestral component

invasion-from-the-steppe-yamnaya

Good timing for the publication of two interesting papers, that a lot of people should read very carefully:

ADMIXTURE

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

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Minimal Corded Ware culture impact in Scandinavia – Bell Beakers the unifying maritime elite

copper-age-late-bell-beaker

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

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Reproductive success among ancient Icelanders stratified by ancestry

iceland-pca

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

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Eurasian steppe dominated by Iranian peoples, Indo-Iranian expanded from East Yamna

yamna-indo-iranian-expansion

The expected study of Eurasian samples is out (behind paywall): 137 ancient human genomes from across the Eurasian steppes, by de Barros Damgaard et al. Nature (2018).

Dicussion (emphasis mine):

Our findings fit well with current insights from the historical linguistics of this region (Supplementary Information section 2). The steppes were probably largely Iranian-speaking in the first and second millennia bc. This is supported by the split of the Indo-Iranian linguistic branch into Iranian and Indian33, the distribution of the Iranian languages, and the preservation of Old Iranian loanwords in Tocharian34. The wide distribution of

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Yleaf: software for human Y-chromosomal haplogroup inference from next generation sequencing data

portugal-bronze-age-admixture

Brief communication (behind paywall) Yleaf: software for human Y-chromosomal haplogroup inference from next generation sequencing data, by Arwin Ralf, Diego Montiel González, Kaiyin Zhong, and Manfred Kayser, Mol Biol Evol (2018), msy032.

Abstract

Next generation sequencing (NGS) technologies offer immense possibilities given the large genomic data they simultaneously deliver. The human Y chromosome serves as good example how NGS benefits various applications in evolution, anthropology, genealogy and forensics. Prior to NGS, the Y-chromosome phylogenetic tree consisted of a few hundred branches, based on NGS data it now contains many thousands. The complexity of both, Y tree and NGS data

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