Palaeoclimatic and Ecological Determinants of Mammalian Host–Pathogen Exposure in Neanderthal-Associated Sites Across Eurasia

Abstract Understanding Neanderthal interactions with Late Pleistocene ecosystems requires examining the interplay between climate, faunal communities, and potential zoonotic exposure pathways. This study analyses 41 Neanderthal-bearing fossil assemblages across Eurasia, focusing on stratigraphic units directly associated with skeletal remains and extant mammal taxa or their close relatives to evaluate ecological conditions relevant to modern host–pathogen associations. By integrating palaeoclimate reconstructions with contemporary host–pathogen data, we assess site-specific environmental conditions, the potential occurrence of invertebrate vectors, and mammalian taxa representing potential reservoir hosts. Rodents, ungulates, wild suids, and carnivores were frequently identified as potential hosts of zoonotic agents, while potential tick- and sand-fly-associated transmission pathways varied with climatic conditions. Species richness and inferred host–pathogen associations varied substantially among assemblages, reflecting differences in local ecological context and faunal composition. These findings provide an ecologically grounded framework for evaluating potential Neanderthal exposure pathways to zoonotic agents. However, the inferred associations represent ecological plausibility rather than direct evidence of infection or transmission, highlighting the need for further palaeopathological evidence to test these predictions.