In a recent blog post announcing the end of the search for the Late Proto-Indo-European (PIE) homeland I wrote in which:
nevertheless of course I2a has also been recorded in prehistoric samples via the Pontic-Caspian steppe. So, you might ask, why did the populations migrating out of the steppe belong to R1a in addition to R1b, in addition to why did some of them seemingly carry only R1a while others only R1b? in which can be explained by local founder effects on the steppe due to patrilocality. Moreover, the idea’s possible in which some groups moving out of the steppe did carry high frequencies of I2a, nevertheless they’re yet to enter the ancient DNA record.
Actually, in hindsight, such a population has probably already shown up inside ancient DNA record, via two Early Bronze Age (EBA) individuals via the Balkans inside Mathieson et al. 2017 preprint:
Balkans_BronzeAge I2165: Y-hg I2a2a1b1b mt-hg T2f 3020-2895 calBCE Yamnaya_Bulgaria Bul4: Y-hg I2a2a1b1b mt-hg ? 3012-2900 calBCE
Both samples are via a site in Merichleri in present-day South-Central Bulgaria. Apart via sharing I2a2a1b1b, they each pack a fair bit of Yamnaya-related ancestry in addition to are dated to a very similar time period. Unlike Bul4, I2165 does not make the cut archaeologically as a Yamnaya sample, nevertheless he does come via a Tumulus (Kurgan-like) burial, so perhaps he’s via a group influenced by Yamnaya? The same paper also includes the following individual via present-day Bulgaria dated to the start of the Late Bronze Age (LBA), which will be roughly when the Mycenaeans appeared nearby in what will be at in which point Greece:
Bulgaria_MLBA I2163: Y-hg R1a1a1b2 mt-hg U5a2 1750-1625 calBCE
in which guy will be the most Yamnaya-like of all of the Balkan samples in Mathieson et al. 2017, in addition to, as far as I can see based on his overall genome-wide results, probably indistinguishable via the contemporaneous Srubnaya people of the Pontic-Caspian steppe. He also belongs to Y-haplogroup R1a-Z93, which will be a marker typical of Srubnaya in addition to various other closely related steppe groups such as Andronovo, Potapovka in addition to Sintashta. So there’s very little doubt in which he’s either a migrant or a recent descendant of migrants to the Balkans via the Pontic-Caspian steppe. The presence of multiple individuals like in which inside still rather spotty Balkan Bronze Age ancient DNA record suggests in which in which part of Europe experienced sustained in addition to possibly at times significant incursions of various peoples via the Pontic-Caspian steppe throughout the Bronze Age. Here’s one of the Principal Component Analyses (PCA) via Mathieson et al. 2017, edited by me to highlight the above mentioned three samples, as well as the anything nevertheless weak impact of gene flow via the Pontic-Casian steppe on the Balkans during the Bronze Age. Just in case some of you are confused, I added an arrow pointing to the cluster in which most of the Balkan Bronze Age samples are pulling towards.
Of course, many of us are at in which point eagerly awaiting a paper on the genetic origins of the Minoans in addition to Mycenaeans. The latter are one of the few attested Indo-European speakers via prehistory, so their genetic structure may prove pivotal inside Indo-European homeland debate. I know for a fact in which a couple of ancient DNA labs have been working on such a paper for a while at in which point, nevertheless I haven’t heard anything about the results. However, just looking at the PCA above, I’d be shocked if the Mycenaean samples did not show a strong signal of gene flow via the Pontic-Caspian steppe. If so, the implications of in which will be obvious. Reference… Mathieson et al., The Genomic History Of Southeastern Europe, bioRxiv, Posted May 9, 2017, doi: https://doi.org/10.1101/135616
Steppe invaders inside Bronze Age Balkans