Isotopic paleoecology (δ13C) from mammals from IUIU/BA and paleoenvironmental reconstruction (δ13C, δ18O) for the Brazilian intertropical region through the late Pleistocene

Abstract

Stable isotopes of carbon and oxygen of fossil specimens are widely used for paleoecological and paleoenvironmental inferences, and there has been an effort to better understand the isotopic paleoecology and chronology of herbivores that inhabited the Brazilian Intertropical Region during the late Quaternary. In the present work, new radiocarbon datings and carbon and oxygen isotopes data for Eremotherium laurillardi, Notiomastodon platensis, Tapirus terrestris, Tayassu pecari, and Mazama gouazoubira are presented, from specimens that lived on Iuiu county (Toca Fria and Jatobá caves), state of Bahia, in the Brazilian Intertropical Region. E. laurillardi was dated as of ∼32 ka BP, representing the oldest direct dating for this species in the Brazilian Intertropical Region, while N. platensis was dated as of ∼25 ka BP. Fossils of the extant species T. pecari, M. gouazoubira, and T. terrestris presented radiocarbon ages of ∼23 ka BP, ∼21 ka BP, and ∼15 ka BP, respectively, showing that some of these species lived in Iuiu during the Last Glacial Maximum. According to our analyses, T. terrestris was the only specialist (δ13C = −11.0‰; piC3 = 0.76; BA = 0.49), whereas the remaining taxa were generalists mixed-feeders (δ13C = −1.3 to −10.0‰; piC3 = 0.24 to 0.69; BA > 0.58). The paleoenvironment reconstruction in Iuiu and other localities in BIR, during ∼32 ka BP to ∼15 ka BP, allow us to suggest that the dry arboreal to open Savanna habitats (rich in grass and shrubs) were the most common environment.