Spatial and temporal heterogeneity in human mobility patterns in Holocene Southwest Asia

Southwest Asia was one of the world's first regions to experience the Neolithic Transition and the emergence of complex hierarchical societies. Analyses of genomic data from this region have suggested high rates of population admixture after the Neolithic, but how human mobility continued through the Holocene has remained unclear. Here we present a spatiotemporal picture of human genetic diversity in Anatolia, Iran, Levant, South Caucasus, and the Aegean. We generated 28 new ancient shotgun genomes from these regions and co-analysed these with 378 ancient and 23 present-day published genomes. We found that genetic diversity within each region steadily increased through the Holocene, with Anatolia tending to display the highest magnitude of genetic change. We further observed that the sources of gene flow shift in time. In the first half of the Holocene, Southwest Asian populations homogenise among themselves. Starting with the Bronze Age, however, regional populations diverge from each other, driven by gene flow from external sources. This shift from short-range to long-range mobility in time was accompanied by an increase in the relative contributions of males in admixture events. Overall, although interregional mobility persisted through the Holocene, its dynamics were highly variable.