Paleoenvironmental inferences from ungulate dental microwear texture analysis during the Middle to Upper Palaeolithic transition in Covalejos (northern Iberia)

The Middle to Upper Palaeolithic Transition (MUPT) in Eurasia (~56-35ka cal BP) took place during Marine Isotopic Stage (MIS) 3, characterized by high climatic instability. The effects of these fluctuations on ecosystems and their impact on late Neanderthals and Anatomically Modern Humans (AMH) remain unclear, particularly on a regional scale. This study focuses on Covalejos cave (Cantabria, Spain), a key archaeological site with a well-preserved and contextualized stratigraphic sequence, including Mousterian and Proto-Aurignacian levels. We applied Dental Microwear Texture Analysis to three ungulate taxa (red deer, horse, and large bovid) hunted and consumed by both human species. This analysis provides new inferences in the ungulate dietary habits during the last weeks of their life and the palaeoenvironmental conditions during the late Neanderthal and first AMH occupations of Covalejos. Our results reveal a mosaic landscape in which red deer maintained a mixed diet throughout the MUPT, and equids showed certain dietary plasticity to this heterogeneous environment. During the Aurignacian, large bovids had feeding habits from grazer in Level C to mixed-feeder in Level B. Despite MIS3 climatic fluctuations, our data, together with other palaeoclimatic proxies, indicate certain local environmental stability supporting diverse plant resources around Covalejos at the moments of human occupations.