Dairying, diseases and the evolution of lactase persistence in Europe.

In European and many African, Middle Eastern and southern Asian populations, lactase persistence (LP) is the most strongly selected monogenic trait to have evolved over the past 10,000 years1. Although the selection of LP and the consumption of prehistoric milk must be linked, considerable uncertainty remains concerning their spatiotemporal configuration and specific interactions2,3. Here we provide detailed distributions of milk exploitation across Europe over the past 9,000 years using around 7,000 pottery fat residues from more than 550 archaeological sites. European milk use was widespread from the Neolithic period onwards but varied spatially and temporally in intensity. Notably, LP selection varying with levels of prehistoric milk exploitation is no better at explaining LP allele frequency trajectories than uniform selection since the Neolithic period. In the UK Biobank4,5 cohort of 500,000 contemporary Europeans, LP genotype was only weakly associated with milk consumption and did not show consistent associations with improved fitness or health indicators. This suggests that other reasons for the beneficial effects of LP should be considered for its rapid frequency increase. We propose that lactase non-persistent individuals consumed milk when it became available but, under conditions of famine and/or increased pathogen exposure, this was disadvantageous, driving LP selection in prehistoric Europe. Comparison of model likelihoods indicates that population fluctuations, settlement density and wild animal exploitation-proxies for these drivers-provide better explanations of LP selection than the extent of milk exploitation. These findings offer new perspectives on prehistoric milk exploitation and LP evolution.

Evidence for the impact of the 8.2-kyBP climate event on Near Eastern early farmers.

The 8.2-thousand years B.P. event is evident in multiple proxy records across the globe, showing generally dry and cold conditions for ca. 160 years. Environmental changes around the event are mainly detected using geochemical or palynological analyses of ice cores, lacustrine, marine, and other sediments often distant from human settlements. The Late Neolithic excavated area of the archaeological site of Çatalhöyük East [Team Poznan (TP) area] was occupied for four centuries in the ninth and eighth millennia B.P., thus encompassing the 8.2-thousand years B.P. climatic event. A Bayesian analysis of 56 radiocarbon dates yielded a high-resolution chronological model comprising six building phases, with dates ranging from before 8325-8205 to 7925-7815 calibrated years (cal) B.P. Here, we correlate an onsite paleoclimate record constructed from δ2H values of lipid biomarkers preserved in pottery vessels recovered from these buildings with changes in architectural, archaeozoological, and consumption records from well-documented archaeological contexts. The overall sequence shows major changes in husbandry and consumption practices at ca. 8.2 thousand years B.P., synchronous with variations in the δ2H values of the animal fat residues. Changes in paleoclimate and archaeological records seem connected with the patterns of atmospheric precipitation during the occupation of the TP area predicted by climate modeling. Our multiproxy approach uses records derived directly from documented archaeological contexts. Through this, we provide compelling evidence for the specific impacts of the 8.2-thousand years B.P. climatic event on the economic and domestic activities of pioneer Neolithic farmers, influencing decisions relating to settlement planning and food procurement strategies.

Genetic continuity, isolation, and gene flow in Stone Age Central and Eastern Europe.

The genomic landscape of Stone Age Europe was shaped by multiple migratory waves and population replacements, but different regions do not all show similar patterns. To refine our understanding of the population dynamics before and after the dawn of the Neolithic, we generated and analyzed genomic sequence data from human remains of 56 individuals from the Mesolithic, Neolithic, and Eneolithic across Central and Eastern Europe. We found that Mesolithic European populations formed a geographically widespread isolation-by-distance zone ranging from Central Europe to Siberia, which was already established 10,000 years ago. We found contrasting patterns of population continuity during the Neolithic transition: people around the lower Dnipro Valley region, Ukraine, showed continuity over 4000 years, from the Mesolithic to the end of the Neolithic, in contrast to almost all other parts of Europe where population turnover drove this cultural change, including vast areas of Central Europe and around the Danube River.