Yamnaya ancestry in Europeans

Four years after the publication of the seminal ancient DNA paper Massive migration from the steppe is a source for Indo-European languages in Europe by Haak et al., we’re still waiting for some of its loose ends to be finally tied up with new samples. In particular…

– if the men of the Corded Ware culture (CWC) were, by and large, derived from the population of the Yamnaya culture, then where are the Yamnaya samples with R1a-M417, the main CWC Y-haplogroup?

– if the men of the Bell Beaker culture (BBC) were also, by and large, derived from the population of the Yamnaya culture, then where are the Yamnaya samples with R1b-P312, the main BBC Y-haplogroup?

– and, most crucially, if R1b-L51, which includes R1b-P312, and is nowadays by far the most important Y-haplogroup in Western Europe, arrived there from the Pontic-Caspian steppe, then why hasn’t it yet appeared in any of the ancient DNA from this part of Eastern Europe or surrounds, except of course in samples that are too young to be relevant?

http://eurogenes.blogspot.com/2019/09/is-yamnaya-overrated.html