Late Pleistocene meso-megaherbivores from Brazilian Intertropical Region: isotopic diet (δ 13C), niche differentiation, guilds and paleoenvironmental reconstruction (δ 13C, δ 18O)

Abstract

ABSTRACT Stable isotopes in enamel, dentin, and bone hydroxyapatite are an important tool in the investigation of the palaeoecology of extinct organisms and are applied as proxies for different environmental parameters (e.g. diet, temperature, guild) that assist in reconstitutions of past environments. Tooth and bone samples of late Pleistocene Toxodon platensis, Eremotherium laurillardi, Notiomastodon platensis, Glyptotherium sp., Hippidion principale, Xenorhinotherium bahiense and Nothrotherium maquinense from several localities in Brazilian Intertropical Region, had δ 13C and δ 18O analysed to infer their paleodiet, guild and niche breadth that allow a reconstruction of past environment in which they lived. Including isotopic data for the horse Equus (Amerhippus) neogeus, the giant lama Palaeolama major, the Cingulatas Panochthus sp. and Holmesina paulacoutoi, and the giant ground sloth Valgipes bucklandi, we can suggest that the Brazilian Intertropical Region presented three guilds: browsers (N. maquinense, V. bucklandi, X. bahiense), mixed-feeders (H. principale, E. laurillardi, T. platensis, N. platensis, P. major, Panochthus sp., H. paulacoutoi) and grazer (E. (A.) neogeus, Glyptotherium sp.). These results indicate a dry environment with mixed vegetation with a predominance of open savanna, suggesting that the area at the time was similar to the current in more arid and open areas of the shrub savanna.