Dental microwear and diet of the latest Miocene ape in southern China (Lufengpithecus lufengensis)

Abstract

Lufengpithecus lufengensis is the latest known Miocene ape in southern China, surviving into an interval of increasingly variable and seasonal conditions approaching the end of the epoch. Inferences of its dietary strategies may help us better understand its flexibility in light of these changing conditions. Previous studies, based solely on dental morphology, suggested that L. lufengensis likely consumed at least some tough foods, but actual evidence of food choice by the species has been lacking. Here, we report on a dental microwear texture analysis of L. lufengensis molars (n = 10) from the Shihuiba site in Yunnan Province, southwest China, dated to 6.9–6.2 Ma. Microwear texture complexity and anisotropy data were generated by white-light confocal profilometry and scale-sensitive fractal analysis and then compared with values for an extant baseline series of primate species with documented differences in diet. Our results indicate that L. lufengensis had a diet similar in central tendencies to tough food feeders, such as Presbytis rubicunda, but significantly different from hard-object feeders, such as Cercocebus atys. Further, L. lufengensis had dispersion of texture complexity values similar to those of extant folivores, but less than those of other primates. This, combined with inferred forested environments and arboreality, is consistent with a varied diet, including folivory, for L. lufengensis. This is consistent with previous assertions that thick enamel in this species was a functional adaptation for tough food rather than hard food consumption. A diet including leaves is seemingly consistent with the flexibility needed for L. lufengensis to respond to increasing seasonal food stress during the Late Miocene in southern China.