Heterogeneous Hunter-Gatherer and Steppe-Related Ancestries in Late Neolithic and Bell Beaker Genomes from Present-Day France.

Summary The transition from the Late Neolithic to the Bronze Age has witnessed important population and societal changes in western Europe. 1 These include massive genomic contributions of pastoralist herders originating from the Pontic-Caspian steppes 2 , 3 into local populations, resulting from complex interactions between collapsing hunter-gatherers and expanding farmers of Anatolian ancestry. 4 , 5 , 6 , 7 , 8 This transition is documented through extensive ancient genomic data from present-day Britain, 9 , 10 Ireland, 11 , 12 Iberia, 13 Mediterranean islands, 14 , 15 and Germany. 8 It remains, however, largely overlooked in France, where most focus has been on the Middle Neolithic (n = 63), 8 , 9 , 16 with the exception of one Late Neolithic genome sequenced at 0.05× coverage. 16 This leaves the key transitional period covering ∼3,400–2,700 cal. years (calibrated years) BCE genetically unsampled and thus the exact time frame of hunter-gatherer persistence and arrival of steppe migrations unknown. To remediate this, we sequenced 24 ancient human genomes from France spanning ∼3,400–1,600 cal. years BCE. This reveals Late Neolithic populations that are genetically diverse and include individuals with dark skin, hair, and eyes. We detect heterogeneous hunter-gatherer ancestries within Late Neolithic communities, reaching up to ∼63.3% in some individuals, and variable genetic contributions of steppe herders in Bell Beaker populations. We provide an estimate as late as ∼3,800 years BCE for the admixture between Neolithic and Mesolithic populations and as early as ∼2,650 years BCE for the arrival of steppe-related ancestry. The genomic heterogeneity characterized underlines the complex history of human interactions even at the local scale.