Faunas from Atapuerca at the Early-Middle Pleistocene limit: The ungulates from level TD8 in the context of climatic change

An extraordinary sequence of fossiliferous levels at the locality of Gran Dolina in the Atapuerca Hills (Burgos, Spain) records the Early-Middle Pleistocene transition. These levels are well dated by a variety of methods, including palaeomagnetism, which locates Lower-Middle Pleistocene boundary at the top of level TD7. Level TD6 is the type site of the species Homo antecessor and yielded over 90% of the European Early Pleistocene human record, while other levels have an archaeological record. The present paper deals with the earliest Middle Pleistocene ungulates of TD8, but we plan to describe the faunas, or at least the ungulates, of levels TD4 to TD8 in the context of the faunal changes that took place around the Early-Middle Pleistocene transition. About 600 fossils could be assigned to a taxon and on this basis the following ungulates are described from TD8: horse Equus altidens, rhinoceros Stephanorhinus aff. etruscus, wild boar Sus scrofa, hippopotamus Hippopotamus sp., red deer Cervus elaphus, giant deer Eucladoceros aff. giulii, giant deer Mega-ceroides solilhacus, fallow deer Dama vallonnetensis, and bison Bison voigtstedtensis. The evolution of these taxa is discussed. The fauna from level TD8 dates to the earliest Middle Pleistocene (stage 19) and differs from later faunas in the retention of a small rhinoceros (Stephanorhinus aff. etruscus) and the latest representative of the genus Eucladoceros. It differs from earlier faunas in having the striped hyaena. Together with the fauna from TD7, in which the Brunhes-Matuyama boundary is recorded, TD8 will provide the most precise criterions for correlation of the Early-Middle Pleistocene boundary on the basis of fossils of large mammals. Profound changes in the global climate system started to take place during the late Early Pleistocene, leading to intensive environmental and faunal change and to human dispersal into Europe. These events mark the beginning of a new time and the Early-Middle Pleistocene boundary is taken somewhere in the middle of this drawn out process. It is taken at a palaeomagnetic change, which is convenient, but this does not appear to be close to an important climatic or faunal change. Ten faunal events are recognized in the period from about 1.2 to 0.5 Ma. The event closest to the Early-Middle Pleistocene boundary is one of the minor events and up to now it is recorded in only few localities, principally in TD8. (C) 2015 Elsevier Ltd and INQUA. All rights reserved.