Predator-prey relationships and the role of Homo in Early Pleistocene food webs in Southern Europe

Predator/prey relationships in Mediterranean Europe during the Early Pleistocene are analysed at the local and regional scales and compared to patterns observed in recent fauna from four regions worldwide (East Africa, South Africa, Southeast Asia and North America). Three subregions (South Eastern, Central and South Western Mediterranean) and three time periods (middle Villafranchian, late Villafranchian and Galerian) are considered. Our approach focuses on large primary consumers and their potential predators; both are defined as mammals weighing over 10 kg. Early Pleistocene food webs are characterised by a unique body size distribution of primary consumers and an extremely rich carnivore guild. These characteristics likely affected ecosystem function in a way not observed in recent communities. The percentage of megafauna species was higher in the middle Villafranchian than in recent fauna, and it increased in the late Villafranchian and early Galerian. The number of predators able to kill megafauna species was high in the late Villafranchian but decreased to modem values in the early Galerian. Competition inside the carnivore guild was similar to recent values in the middle Villafranchian and early Galerian but higher in the late Villafranchian. Hominins likely entered Europe during the late Villafranchian, when survival opportunities for a hunter-gatherer were low and hominins were most likely relegated to a marginal role in the palaeocommunity. This scenario changed in the early Galerian with the extinction of several predators and relatively reduced intraguild competition. (C) 2012 Elsevier B.V. All rights reserved.