Broomcorn millet (Panicum miliaceum L.) is not one of the founder crops domesticated in Southwest Asia in the early Holocene, but was domesticated in northeast China by 6000 bc. in europe, millet was reported in Early Neolithic contexts formed by 6000 bc, but recent radiocarbon dating of a dozen 'early' grains cast doubt on these claims. Archaeobotanical evidence reveals that millet was common in Europe from the 2nd millennium bc, when major societal and economic transformations took place in the Bronze Age. We conducted an extensive programme of AMS-dating of charred broomcorn millet grains from 75 prehistoric sites in Europe. Our Bayesian model reveals that millet cultivation began in europe at the earliest during the sixteenth century bc, and spread rapidly during the fifteenth/ fourteenth centuries bc. Broomcorn millet succeeds in exceptionally wide range of growing conditions and completes its lifecycle in less than three summer months. Offering an additional harvest and thus surplus food/fodder, it likely was a transformative innovation in European prehistoric agriculture previously based mainly on (winter) cropping of wheat and barley. We provide a new, high-resolution chronological framework for this key agricultural development that likely contributed to far-reaching changes in lifestyle in late 2nd millennium bc 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 last 10,000 years 1 . While LP selection and prehistoric milk consumption must be linked, considerable uncertainty remains concerning their spatiotemporal configuration and specific interactions 2,3 . We provide detailed distributions of milk exploitation across Europe over the last 9k years using c. 7,000 pottery fat residues from >550 archaeological sites. European milk use was widespread from the Neolithic period onwards but varied spatially and temporally in intensity. Surprisingly, comparison of model likelihoods indicates that LP selection varying with levels of prehistoric milk exploitation provides no better explanation of LP allele frequency trajectories than uniform selection since the Neolithic. In the UK Biobank 4,5 cohort of ~500K 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 other hypotheses on 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 that under particular conditions and microbiological milieux this was disadvantageous, driving LP selection in prehistoric Europe. Comparison of model likelihoods indicates that population fluctuations, settlement density and wild animal exploitationproxies for these driversprovide better explanations of LP selection than the extent of milk exploitation. These findings offer new perspectives on prehistoric milk exploitation and LP evolution.

Based on Optically Stimulated Luminescence (OSL) and radiocarbon dating we establish chronologies of colluviation and alluviation in different floodplain sections of the northwestern Wetterau loess basin (Germany). Similar to some other European valley floors, Holocene floodplain aggradation is marked by two important breaks: (1) a millennial-scale delay between the Neolithic agricultural colluviation and floodplain aggradation. In loess catchments agricultural colluviation started at about 7000 cal. BP and anthropogenic floodplain aggradation only at about 2200 ± 200 cal. BP; (2) a centennial-scale variability in a temporary rise in rates of anthropogenic floodplain aggradation (up to 3.6 ± 1.7 mm/yr) during the High Middle Ages in directly neighbouring reaches. Independent archaeologic, historic, and vegetation records document distinct agricultural histories of hillsides and floodplains and highlight the importance of hydrosedimentary connectivity as compared with land use intensity. The late Iron Age start of alluviation can be linked to the introduction of an integrated land use system with intense cultivation on hillsides and immediate neighbouring floodplains. The centennial-scale variability of medieval peak aggradation is a result of the successive introduction (or temporal failure) of hydraulic water milling infrastructure. Using palaeoecological and geomorphological information for reconstructing cause and consequence of sediment redistribution in coupled human-natural systems requires firm information about the spatial organisation and technological abilities that are associated with socio-agricultural transformations.

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