Thứ Năm, 1 tháng 3, 2018

Awesome substructure within Czech Corded Ware

This is where the three Czech Corded Ware samples from Olalde et al. 2018 cluster in my Principal Component Analysis (PCA) of ancient West Eurasian genetic variation.



The two individuals belonging to Y-haplogroup R1a look like they might be straight from the Pontic-Caspian (PC) steppe. That's because they're sitting right next to an Eneolithic sample from the North Pontic part of the PC steppe

Thứ Hai, 26 tháng 2, 2018

The Yamnaya outlier

For a while now I've been arguing that the more exotic and southern, non-Eastern European Hunter-Gatherer (EHG), part of the Yamnaya genotype mostly made its way into the Pontic-Caspian steppe via female mediated gene flow, probably as a result of the practice of female exogamy with populations in the North Caucasus. For instance:

A plausible model for the formation of the Yamnaya genotype

The

Chủ Nhật, 25 tháng 2, 2018

Bronze Age Sicilian vs modern-day Sicilians

This is the first in a series of quick and simple posts focusing on genetic shifts across Eurasia since the Bronze Age. Any thoughts about what we're seeing in these Global25/nMonte models and Principal Component Analysis (PCA) below? Feel free to let me know in the comments.

By the way, the Bronze Age Sicilian, from a "Beaker" burial site at Partanna, western Sicily, and dated to 2500–1900 BCE

Thứ Sáu, 23 tháng 2, 2018

A swarm of locusts?

The dam has truly broken. Below is my usual Principal Component Analysis (PCA) of ancient West Eurasian genetic variation, except now also featuring the new samples from Mathieson et al. 2018 and Olalde et al. 2018. Incredibly, there are almost a thousand ancient individuals on this plot. The relevant datasheet is available here.



My imagination is probably running wild from all of this

Thứ Ba, 20 tháng 2, 2018

Migration of the Bell Beakers—but not from Iberia (Olalde et al. 2018)

At last, after many months of waiting, the paper that I've been calling the Bell Beaker Behemoth will finally appear at Nature today or tomorrow, depending on your time zone [Update: the paper is here]. The accompanying dataset is already online, and it's twice as big as what the paper's bioRxiv preprint promised, packing 400 new samples from Neolithic, Copper Age and Bronze Age Europe (freely

Chủ Nhật, 18 tháng 2, 2018

C for Cheddar Man (?)

A new preprint has just appeared at bioRxiv on the Mesolithic to Neolithic transition and resulting massive population shift in Britain. It features genome-wide data from six Mesolithic and 67 Neolithic individuals, including the famous Cheddar Man.

Population Replacement in Early Neolithic Britain by Brace et al.

The peculiar thing about this preprint is that it doesn't list the Y-haplogroups

Thứ Năm, 15 tháng 2, 2018

Modeling genetic ancestry with Davidski: step by step

There are many different ways to model your genetic ancestry. I prefer the Global25/nMonte method (see here). This is a step by step guide to modeling ancient ancestry proportions with this simple but powerful method using my own genome.



As far as I know, the vast majority of my recent ancestors came from the northern half of Europe. This may or may not be correct, but it gives me somewhere to