Dietary paleoecology of bison and horses on the mammoth steppe of eastern Beringia based on dental microwear and mesowear analyses

In contrast to the modern Arctic, high-latitude ecosystems of Late Pleistocene supported a diverse range large mammalian herbivores, including abundant bison (Bison priscus) and horses (Equus sp.). This ‘mammoth steppe’ biome has no extant analog tundra vegetation is likely incapable supporting such high density mammals. Compared Arctic ecosystems, higher diversity biomass mammal populations may have been sustained by more nutritious forage and/or dietary niche partitioning. We used dental microwear texture analysis mesowear priscus, Equus sp.) characterize diet assess degree which differences co-existence these dominant competing herbivores on mammoth steppe. Additionally, we compared specimens Alaska (reintroduced Bison athabascae introduced bison) published data for bovids equids. Our results demonstrate that had less abrasive diets than obligate grazers, suggesting “grazers” steppe incorporated forbs in their grazers. Furthermore, ate foods with similar textures, indicating partitioning alone cannot explain co-occurrence. However, taphonomic between horse indicate potential spatial or temporal during Pleistocene.