🐎 How steppe ancestry formed on the North Pontic frontier

Ancient DNA from the lower Dnipro–Don region shows three pulses that built the steppe ancestry later carried by Yamnaya. First, Trypillia farmers in today’s Ukraine mixed only a little with steppe-arriving groups — on average ~81% Balkan farmer, ~14% Balkan hunter-gatherer, ~5% Caucasus–Lower Volga (CLV).

Next, Usatove formed by roughly ~55% Trypillia + ~45% CLV-related ancestry. Finally, Yamnaya emerged ~4000 BCE from a fusion of CLV-derived people with Dnipro–Don hunter-gatherers, with the earliest “Core Yamnaya” individual already present at Mykhailivka (3635–3383 BCE) — right in the lower Dnipro heartland.

Takeaway: Steppe ancestry in Yamnaya crystallized in Ukraine’s lower Dnipro–Don zone by combining CLV migrants with local foragers, after smaller inputs into nearby farmer groups like Trypillia and Usatove.

Source: Nikitin et al., 2025. A genomic history of the North Pontic Region from the Neolithic to the Bronze Age.