Sumatran orangutan diets in the Late Pleistocene as inferred from dental microwear texture analysis

Orangutan (Pongo spp.) fossils have been found throughout much of Pleistocene Southeast Asia. Today, Pongo is restricted to three living species on the islands Borneo and Sumatra. They are predominately frugivores, during fruit masting events their diets can consist entirely fruit. However, food procurement strategies between differ thus species. Sumatran orangutans abelii) largely able fall back non-masting species, such as figs, that they maintain higher quality compared Bornean counterparts pygmaeus), who ingest more lower tougher foods events. fossil remain unknown. We investigated from deposits Padang Highlands, western Sumatra, using dental microwear texture analysis. tested whether were similar those orangutans, all great apes generally, macaques occupy habitats modern in order gain insights into palaeoenvironments present consumed less tough than pygmaeus, presumably fleshy fruits (absent significant seed mastication). no differences amount hard object feeding orangutans. Taken together, we suggest Sumatra had abelii, indicating not a contributing factor intake Finally, anisotropy values orangutan may be an important marker for Pleistocene.