The extinction of the giant hyena Pachycrocuta brevirostris and a reappraisal of the Epivillafranchian and Galerian Hyaenidae in Europe: Faunal turnover during the Early-Middle Pleistocene Transition

The giant, short-faced hyena Pachycrocuta brevirostris was the largest Hyaenidae ever existed and the one that perfectly embodied the distinctive bone-cracking adaptations of this mammal family. Its dispersal into Europe is regarded as a biochronological marker of the Late Villafranchian at ∼2.0 Ma, and its potential ecological interactions with other carnivorans and early Homo populations diffusing Out of Africa have given rise to extensive discussions. Nevertheless, our comprehension of the extinction of P. brevirostris remains vague. Here, we first critically evaluate the European fossil record of the species and then we review the whole Epivillafranchian and Galerian Hyaenidae record, including P. brevirostris, Crocuta crocuta and "Hyaena" prisca. Biometric comparisons with other extinct and extant bone-cracking hyenas are carried out.

In contrast to a common view, we recognize that there is neither evidence of a persistence of P. brevirostris beyond the Early-Middle Pleistocene boundary, nor of a coexistence between the giant hyena and C. crocuta. The replacement between the two species, which was also accompanied by the arrival of "H." prisca, occurred at ∼0.8 Ma and can serve as a marker of the Epivillafranchian-Galerian turnover, part of the faunal renewal that reflects the response of mammal communities to the Early-Middle Pleistocene Transition. Moreover, we clarified that Pliocrocuta perrieri and "H." prisca were different species, and that the latter was relatively more widespread than often assumed, being recorded from localities spanning in age almost the whole Middle Pleistocene and even the early Late Pleistocene.