DESCRIPTION OF NEW FOSSIL TEETH OF GIGANTOPITHECUS BLACKI FROM SANHE CAVE,CHONGZUO,GUANGXI IN SOUTHERN CHINA WITH COMMENTS ON EVOLUTIONARY TRENDS IN GIGANTOPITHECUS DENTAL SIZE
广西崇左三合大洞新发现的巨猿牙齿化石及其演化意义

Fifty-six isolated teeth of Gigantopithecus blacki was discovered in Sanhe Cave in Chongzuo Ecological Park,Guangxi Province in Southern China during the joint excavation of the Institute by Vertebrate Paleontology and Paleoanthropology,Chinese Academy of Sciences and the Chongzuo Biodiversity Research Institute,Peking University.Sanhe Cave(22°16.493′N,107°30.663′E)is a cave developed in the calcareous karst rocks,about 200m above sea level.Among the 56teeth,24are from upper jaws and 32from lower jaws.Except for the upper canine,all tooth types are presented.Most tooth crowns are completely preserved,but most roots are damaged to various degrees.The whole assemblage represents at least 5individuals of Gigantopithecus blacki,including infant,juvenile,young,adult and old individuals inferred from the dental development,eruption or wearing stages.Tooth crown size of Gigantopithecus blacki from Sanhe Cave is measured and compared with those of other 7 sites found in China in order to explore the evolutionary trends of dental size of the species.Overall,the mean tooth size of Sanhe Cave seems to be larger than those of the Early Pleistocene Gigantopithecus Cave of Liucheng and,Longgupo of Wushan,Mohui Cave of Tiandong,and Longgu Cave of Jianshi,but comparable to those of the late Early Pleistocene or early Middle Pleistocene Wuming and Bama.The associated large mammal fauna in Sanhe Cave including Ailuropoda wulingshanensis,Cuon antiquus,and Tapirus sinensis are different from the typical members of the Early Pleistocene animals such as Ailuropoda microta,Cuon dubicus,Tapirus sanyuanensis.The preliminary comparison supports the previous observation that tooth size of Gigantopithecus blacki became larger from Early to Middle Pleistocene.However,two other questions need to be addressed: whether multiple populations of Gigantothecus co-existed in Liucheng specimens which show a large variation in tooth size,and how sex ratio or sex dimorphism of Gigantopithecus attributed to the tooth size variation observed.