Glacial/interglacial climate variability in southern Spain during the late Early Pleistocene and climate backdrop for early Homo in Europe

Abstract

The oldest evidence of a human presence in western Europe is currently documented at the late Early Pleistocene sites of Barranco León and Fuente Nueva 3 (Guadix-Baza Basin, SE Spain), dated respectively to 1.4 and 1.2 Ma. Understanding the climatic variability that these hominins encountered and coped with is of outstanding importance for placing their activities in an ecological context and understanding their capacity to adapt to changing conditions. Glacial-interglacial variability during this period was considerably less intense than during later phases of the Pleistocene. To date, however, no quantitative estimates are available for this climate variability in Early Pleistocene hominin sites, and no ‘cold’ reconstructions directly associated with the early hominin occupations of Europe have been performed either. Here stratigraphically constrained quantitative climatic reconstructions are provided for the sites of Barranco León and Fuente Nueva 3, using an improvement on the Mutual Ecogeographic Range method by projecting the niche envelope of the extant representatives of Ophisaurus sp. We ascertain differences in temperature and rainfall between the different layers of the two sites, in line with previous reconstructions that revealed warm, humid periods (‘interglacial’) as well as more temperate but drier periods (‘glacial’'), consistent with Early Pleistocene climate cyclicity. Our new estimates suggest that late Early Pleistocene hominins, though conditioned to some degree by climatic factors, were able to deal with changing climatic and environmental conditions (‘interglacial’ and ‘glacial’') in the southwestern extremity of the European continent.