Isotopic palaeoecology (delta C-13) of three faunivores from Late Pleistocene of the Brazilian intertropical region

The palaeoecology of megamammals has been commonly accessed by stable isotope. Particularly in the Americas, this approach has been focusing efforts on the study of intertropical species, especially from a key paleozoogeographical region in the Late Quaternary of South America: the Brazilian Intertropical Region (BIR). Here we present an isotopic study (delta C-13) conducted on bioapatite samples of Smilodon populator, Protocyon troglodytes and Arctotherium wingei from the BIR. We discuss their potential prey preferences, niche width and overlap, and paleoenvironmental reconstitutions. Our results suggest a generalist carnivorous diet for P. troglodytes (delta C-13 = - 5.0 parts per thousand; B-A = 0.83), a specialist C-3 herbivorous diet and opportunistic scavenger behaviour for A. wingei (delta C-13 = - 11.0 +/- 2.1 parts per thousand; B-A = 0.00), and a specialist carnivorous diet for S. populator (delta C-13 = - 8.5 +/- 1.6 parts per thousand; B-A = 0.06). Within the Late Pleistocene of the BIR, P. troglodytes possibly inhabited open savanna-like environments, while S. populator and A. wingei occupied arboreal savanna forests. An atypical preference for small and medium-size prey for the predator S. populator, and a mainly herbivorous diet with a slight amount of meat for the bear A. wingei is also discussed.