By sequencing 727 ancient individuals from the Southern Arc (Anatolia and its neighbors
in Southeastern Europe and West Asia) over 10,000 years, we contextualize its Chalcolithic
period and Bronze Age (about 5000 to 1000 BCE), when extensive gene flow entangled
it with the Eurasian steppe. Two streams of migration transmitted Caucasus and Anatolian/Levantine
ancestry northward, and the Yamnaya pastoralists, formed on the steppe, then spread
southward into the Balkans and across the Caucasus into Armenia, where they left numerous
patrilineal descendants. Anatolia was transformed by intra–West Asian gene flow, with
negligible impact of the later Yamnaya migrations. This contrasts with all other regions
where Indo-European languages were spoken, suggesting that the homeland of the Indo-Anatolian
language family was in West Asia, with only secondary dispersals of non-Anatolian
Indo-Europeans from the steppe.
