Middle Pleistocene climate and habitat change at Zhoukoudian, China, from the carbon and oxygen isotopic record from herbivore tooth enamel

Abstract

The Pleistocene deposits at Zhoukoudian, often referred to as the “Peking Man” site, contain dental remains from a diverse group of herbivores, including Equus sanmeniensis, Cervus elaphus, Cervus nippon, Megaloceros pachyosteus, Sus lydekkeri, and Dicerorhinus choukoutienensis. The carbon and oxygen isotopic compositions of structural carbonate within the enamel of these teeth are used to reconstruct the paleodiet and paleoenvironment of the mammals. The δ 13C values of enamel from Zhoukoudian range from −2.3‰ to −13.0‰, indicating that these mammals consumed between ∼25% and 100% C 3 plants. The presence of significant amounts of C 4 plants in the diets of some herbivore species indicates that at the onset of the Middle Pleistocene local habitats included mixed C 3/C 4 vegetation. By approximately 470,000 yr ago, C 3 plants dominated the diets of herbivores studied, suggesting that the abundance of C 4 flora had decreased in the area. For all deer analyzed in this study, the values of δ 13C and δ 18O decrease substantially from about 720,000 to 470,000 yr ago. This trend may be due to a strengthening of the winter monsoon during the Middle Pleistocene.