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

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. 4–8 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. • Sequencing of 24 human genomes from France dated to ∼3,400–1,600 cal. years BCE • These genomes show heterogeneous hunter-gatherer and steppe-related ancestries • Paris Basin Neolithic and Mesolithic groups admixed as recently as ∼3,800 years BCE • Admixture with steppe herders in southern France dated as early as ∼2,650 years BCE The Late Neolithic to Bronze Age transition was marked by major genetic changes in Europeans but is poorly documented at the genomic level in France. With new extensive whole-genome time series for this period, Seguin-Orlando et al. extend the time frame during which steppe-related and hunter-gatherer ancestries entered and vanished in this region. [ABSTRACT FROM AUTHOR]