Downsizing in the Late Pleistocene: Sus scrofa (Suidae, Mammalia) in the Apulian peninsula (Southern Italy)

The extant wild boar Sus scrofa has one of the largest geographical ranges of all mammals, and from its appearance in the late Early Pleistocene (Epivillafranchian) it is also widely represented in the European fossil record. There is a general consensus in recognizing that early wild boars are larger than Late Pleistocene specimens, but no agreement exists neither on the chronology of this transition, nor if only one occurred. From the end of 1800s, the Apulian peninsula (Southern Italy) represented a key region to study Mediterranean Quaternary paleoenvironmental dynamics. This territory is rich in mammal remains, often associated to lithic tools and human remains. Consequently, this region has a remarkable research tradition, which constitutes a solid background to test S. scrofa size variability through time. Here, the wild boar craniodental material from several late Middle and Late Pleistocene sites (Aurelian assemblages) of Apulia is presented for the first time. The studied sample includes specimens from different localities with well-documented palaeobiological, biochronological, and geo-archaeological data (e.g., Grotta Romanelli, Melpignano, and Avetrana). The results support that S. scrofa populations underwent a size reduction during the early Late Pleistocene. The biochronological and paleoenvironmental implications of this bioevent are discussed in the broad scenario of Aurelian faunal impoverishment, when other long-lasting species such as the straight-tusked elephant and the hippo disappeared from the region.