Simultaneous Late Pleistocene Megafauna Extinctions in Southern Patagonia

METCALF, J.; BARNETT, R.; MARTIN, F.; BRAY, S.; VILSTRUP, J.; ORLANDO, L.; SALAS-GISMONDI, R.; LOPONTE, D.; MEDINA, M.; DE NIGRIS, M.; CIVALERO, T.; FERNANDEZ, P.; GASCO, A.; DURAN, V.; OTALOLA, C.; GIL, A.; PAUNERO, R.; PREVOSTI, F.; BRADSHAW, C.; WHEELER, J.; BORRERO, L.; AUSTIN, J.; COOPER, A.

San Rafael

Conferencia; 12th International Conference of Archaeozoology; 2014

At the end of the Pleistocene, South America suffered the greatest loss of megafauna diversity of any continent. Currently, the taxonomy, diversity and timing of the megafauna extinction are not well quantified. Using ancient DNA, we provide the first phylogenetically based taxonomical description of five megafauna taxa, including two camelids, two felids and a large bear living in southern Patagonia in the Late Pleistocene. We discovered a previously unknow subspecies of Lama guanicoe that is distinct from all the extant camelids of the region. We also found that the morphologically distinct Lama gracilis was genetically distinct camelid lineage. We confirm that the extinct giant jaguar living in the Pleistocene southern Patagonia was a distinct subspecies of Panthera onca (P.o. mesembrina), as was described on the base of fossil cranial remains. Althought an ancient Puma concolor haplotype recovered from southern Patagonia has not been sampled in modern surveys, our results show that closely related diversity survived the Pleistocene-Holocene transition in South America. Finally, we place the short-faced bear Arctotherium tarijense in the Tremarctine family with the extant spectacled bear and extinct North American short-faced bear. Wecoupled these ancient DNA results with 71 new radiocarbon dates for these and three more megafaunal taxa for which genetic data were previously published: Smilidon populator, Mylodon darwinii and Hippidion saldiasi. We show that human arribal and regional transition to drier, warmer Holocene climate were associated with the megafaunal community´s collapse, with most species likely disappearing in less than 1000 years and contemporaneous with human arrival.