The Epivillafranchian and the arrival of pigs into Europe

Abstract

Suids are found in Europe before and during the Olduvai subchron, including the Fonelas P-1 (~2.0 Ma), in which the remains have been ascribed to Potamochoerus magnus, and many other localities that record the presence of Sus strozzii. However, there is no pig record in the biochronological range comprised between the post Tasso Faunal Unit, which marks the base of the Late Villafranchian (~1.8 Ma), and their arrival in Western Europe at layer TE9 from Sima del Elefante, Atapuerca, Northern Spain (~1.2 Ma), where pigs are recorded under the name of Sus sp., and at the sites of Untermassfeld, Vallonnet and layer EVT12 of Vallparadís Estació, dated 1.1-1.0 Ma (MIS31). Later, the genus Sus is recorded everywhere in Europe as a ubiquitous member of the Epivillafranchian/Galerian and posterior faunas. When pigs are in an ecosystem, they use to be abundant in the large mammal community given their opportunistic feeding behavior and high reproductive success. For this reason, suids are usually preserved in the fossil assemblages after their dispersal and colonization of a geographic region. The arrival of suids phylogenetically related to Sus gr. scrofa into Europe marks the end of the Late Villafranchian and the beginning of the Epivillafranchian, which is approximately dated at ~1.2 Ma. Given that suids are omnivorous, generalist mammals with bunodont teeth that do not tolerate very low temperatures, this suggests that their colonization of Europe can be related to a change in the ecosystems and climate. In addition, the arrival of suids postdates the earliest arrival of hominins into Western Europe, which is documented at the Orce sites of Barranco León-D and Fuente Nueva-3 (~1.5-1.2 Ma). In these sites, rich faunal assemblages, abundant lithic artifacts and one human tooth have been unearthed after more than twenty years of xcavations, but no evidence of pigs has yet been detected.