Diets and environments of late Cenozoic mammals in the Qaidam Basin, Tibetan Plateau: Evidence from stable isotopes

The timing history and driving mechanisms of C4 expansion and Tibetan uplift are hotly debated issues. Paleoenvironmental evidence from within the Tibetan Plateau is essential to help resolve these issues. Here we report results of stable C and O isotope analyses of tooth enamel samples from a variety of late Cenozoic mammals, including deer, giraffe, horse, rhino, and elephant, from the Qaidam Basin in the northeastern Tibetan Plateau. The enamel-delta C-13 values are < -89 parts per thousand for modern samples and