PREVOSTI Francisco Juan
congresos y reuniones científicas
The mammalian predator guild of the Southern Patagonia during the late Pleistocene: ecomorphology, taphonomy and stable isotopes
FRANCISCO J. PREVOSTI; FABIANA MARTIN
Congreso; XVIII INQUA Congress; 2011
During the late Pleistocene Patagonia had a rich fauna of large mammals including some megamammals (body size above one tone). This includes a ground sloth (Mylodon darwini), horse (Hippidion saldiasi), and some species of camelids (Lama guanicoe, Lama gracilis), at least in comparison with the present one. The carnivore guild was represented by several extinct taxa like a sabretooth cat (Smilodon), the Patagonian panther (Panthera onca mesembrina), a short faced bear (Arctotherium tarijense) and a large fox (Dusicyon avus), but also the living puma (Puma concolor). Here for each predator we estimated body size, prey size and diet habits of each predator, to reconstruct the relationships within the predator guild and between these carnivores and their potential preys. The results are compared with the available taphonomic information for the region, and with preliminary stable isotopes results. The guild had three felids that were large hypercarnivores, and two of them (Smilodon, P. onca) could prey on every large mammals. The short face bear was mainly an omnivore, but surely could have scavenged and occasionally hunted medium-large mammals like camelids and horses. D. avus was slightly larger and more carnivorous than the living culpeo fox (Lycalopex culpaeus), and preyed mostly on small mammals (rodents) but occasionally on camelids. These indicate that large mammals (e.g. camelids and horses), could be the more frequent preys of the whole guild. Taphonomic studies showed that P. onca mensembrina gnawed bones of Mylodon, Hippidion and camelids, which suggest that these were frequent preys, and agrees with the ecomorphological interpretations. The Patagonian panther and fox bones also regularly appear gnawed, suggesting intraspecies consumption. One interesting point of these faunas is that the diversity of potential preys is lower than that observed in lower latitudes (e.g. Pampean Region) but the number of predators is similar.