Diets of mammalian fossil fauna from Kanapoi, northwestern Kenya

Carbon isotope ratios of mammalian teeth from the Kanapoi site in northern Kenya are interpreted in the context of C₃ and C₄ derived resources to investigate the paleoecology of Australopithecus anamensis. δ¹³C values of large mammals, when compared at the taxon level, show an ecosystem that is strongly biased towards mixed feeders and browsers. However, sufficient C₄ resources were present such that some C₄ dominated grazers were also present in the large mammal fauna. Analyses of micromammals shows that their diets were C₃ dominated or C₃-C₄ mixed. Carbon isotope studies of primates shows that the major primate tribes-Colobini, Papioini, Hominini-all made some use of C₄ resources in their respective diets; the Hominini had a higher fraction of C₃ diet resources than the other primate tribes represented in the fossil record.