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.

Initial Upper Palaeolithic lithic industry at Cueva Millán in the hinterlands of Iberia.

The extended period of coexistence between Neanderthals and Homo sapiens in Europe coincided with the emergence of regionally distinctive lithic industries, signalling the onset of the Upper Palaeolithic. The Iberian Peninsula was on the periphery of pioneering Upper Palaeolithic developments, with archaeological remains primarily found in northern territories. We report the discovery of an initial Upper Palaeolithic lithic industry at Cueva Millán in the hinterlands of Iberia. This industry, termed here Arlanzian, not only represents the earliest and southernmost evidence of such industries in Iberia but also lacks a direct counterpart. However, it exhibits chronological and technological parallels with the lithic industries associated with the earliest expansion of Homo sapiens throughout Eurasia. We interpret this as potential evidence of its intrusive nature, but not necessarily associated with a migration event, as more complex scenarios derived from inter-population connectivity must be also considered. The biological identity of the Arlanzian makers remains unknown, but they coexisted with declining Neanderthal groups from neighbouring territories.

Geochemical fingerprint of agricultural liming as a regular management practice in Modern-period Basque farming.

The Modern period in Europe is marked by the introduction of deep agricultural changes. In the Basque Country (northern Spain), the implantation of an intensive crop rotation was made possible by the expansion of agricultural liming, although the extent and implications of this practice have not been previously explored in depth. The present paper proposes a multidisciplinary approach to this question, based on the combined analysis of archival sources, toponymy, visual prospection focused on the presence of limekilns, and agricultural soil coring in four local contexts of the Atlantic Basque Country. The results show, for the first time, evidence of concurrent and widespread liming in this territory at the edge of the 18th century, with strong implications for the model of agricultural management in the communities involved. The spreading of mineral fertilisation reflects an intensification in the forms of agricultural management, in the framework of a new relationship between land and labour that emerged after the introduction of American crops. Continuous liming for more than 200 years exerted a deep impact in the analysed soils, with interesting socio-economic and ecological implications that are representative of the potential short-term effects that changing relationship between humans and their socio-ecological environment may produce in agricultural soils.

On the origin of rural landscapes: Looking for physico-chemical fingerprints of historical agricultural practice in the Atlantic Basque Country (N Spain).

Evolution and change in agricultural practice is a major factor in the codification of social relations and represents one of the main resources employed by human societies to establish a durable relationship with their environment. Using a multi-proxy integrated approach, this paper seeks to decipher the long-term dynamics that have shaped agricultural landscapes in the Basque Country (N Spain). Social and economic indicators (archival records, toponymy and oral sources) are used along with geological core sampling (geochemistry, magnetic, palynological and carpological analyses) to reconstruct a diachronic sequence of human settlement and agricultural management in the village of Aizarna over the last ~1500 years. The oldest records obtained refer to non-agricultural human activities dating back to the Roman period. Later on, traces of agricultural landscape-transformation can be divided into four main phases: 1) the onset of terraced agriculture, defined by the clearance and terracing of previous forested areas during the Early Middle Ages; 2) a Late Medieval reorganisation, with new terraces being (re)constructed close to dispersed farmsteads, linked to the emergence of the modern rural landscape; 3) a new model of intensive polyculture developed during the Modern period as a consequence of the introduction of new crops of American origin; and 4) the mechanisation and commercialisation of the agricultural production over the 20th century. These results provide a valuable pathway for the investigation of currently inhabited rural contexts, and offer, for the first time in this region, an overview on long-term landscape construction in the Atlantic areas of the Basque Country.