Stable isotope dietary assessment of Smilodon (Carnivora, Felidae) from central Argentina during the latest Pleistocene

SANZ-PÉREZ, DÁNAE; HERNÁNDEZ FERNÁNDEZ, MANUEL; TOMASSINI, RODRIGO; MONTALVO, CLAUDIA; DOMINGO, LAURA

Barcelona

Otro; 20th Annual Conference of the European Association of Vertebrate Palaeontologists; 2023

Institute Catala de Paleontologia

The sabertooth Smilodon is a felid from the Pleistocene of the Americas, placed at the top of the food web, that participated in the Great American Biotic Interchange. The South American Smilodon populator was capable of hunting large prey weighting up to 2,000 kg. In this contribution, we evaluate the diet of S. populator from the tooth enamel carbon isotope composition (δ13C) analyzed on 65 bioapatite samples of this carnivore (n=10) and its prey (n=55). Two Late Pleistocene fossiliferous sites of central Argentina were studied: Santa Rosa (~28 ka) and Playa del Barco (~19 ka). Potential prey includes both South American endemic species of notoungulates, litopterns, and pilosans, and North American immigrant species of artiodactyls, perissodactyls, and proboscideans. The δ13C range (–8.6 to –6.6‰) suggest an open environment as the preferred prey habitat. The δ13C range of this hypercarnivore in both sites is narrow compared to the dispersion of values of the different herbivores. We used the MixSIAR Bayesian mixing model to evaluate the contribution of potential prey to its diet. This model showed that all herbivores could have been potential prey for this predator in Santa Rosa and Playa del Barco, although at the latter locality it showed a preference for Megatherium and Stegomastodon. Similar results were obtained from samples from other localities of Argentina. Therefore, at a moment close to the extinction of the megafauna in the Pleistocene–Holocene boundary, Smilodon inhabited open environments where it was a generalist felid that preyed on a wide suite of taxa.