The rise and transformation of Bronze Age pastoralists in the Caucasus

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Ancient DNA tracks 6,000 years of Caucasus pastoralist rise and fall.

This study sequenced 131 ancient genomes from 38 sites across the Caucasus, spanning the Mesolithic to the Late Bronze Age. It shows that north and south of the mountains were genetically distinct early on: northern hunter-gatherers had Eastern hunter-gatherer ancestry, while southerners carried Caucasus hunter-gatherer ancestry plus growing Anatolian farmer admixture. Later, steppe ancestry formed and spread, but the peak of pastoralist expansion was genetically stable, not a mass migration.

• Mesolithic Caucasus populations were strongly split north-south: Eastern hunter-gatherer ancestry in the north, Caucasus hunter-gatherer ancestry with East Anatolian farmer admixture in the south.
• The characteristic West Eurasian steppe ancestry formed during the Eneolithic, with increased mountain-steppe interaction linked to Maykop cultural developments.
• Early and Middle Bronze Age pastoralist expansion peaked with long-term genetic stability, while the Late Bronze Age saw gene flow from multiple sources and steppe ancestry absorbed into highland groups.

Sample interpretation

The site dataset includes 142 samples, with 69 resolved Y-chromosome lineages. Y-haplogroups are dominated by R-M12149 and R-V1636 (5 each), followed by R-M269 and R-Z2103 (4 each), plus J and H lineages. Mitochondrial DNA is led by I1b (7), then U4c1 and K1a (5 each), and T2c1a and T1a1 (4 each). The listed cultures are Steppe Eneolithic (5) and Eneolithic (2), reflecting the study's focus on early pastoralist contexts.

For genealogy enthusiasts

For ancestry enthusiasts, this shows the Caucasus was a key genetic crossroads: early hunter-gatherer differences, then steppe ancestry formation, and later stability during expansion. It helps explain why modern Caucasus and steppe populations carry mixed ancestries, and warns against assuming all cultural spreads were mass migrations.