广西崇左三合大洞新发现的巨猿牙齿化石及其演化意义

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

文章报告了在广西崇左生态公园三合大洞中新发现的巨猿牙齿化石,这些新化石材料为研究巨猿演化及华南地区更新世动物群时代演化及环境变迁有着重要意义。三合大洞共出土巨猿牙齿56枚,除上犬齿,其他上、下颌牙齿种类齐全;从牙齿发育及磨损情况判断,这些材料代表了婴幼年、青少年、青壮年、中年及老年各年龄阶段的至少5个个体。测量了牙齿大小,并与其他的巨猿化石点的材料进行对比,认为三合大洞的巨猿牙齿与武鸣、巴马的巨猿有可比性。在此基础上,结合动物群组合特征及时代意义,探讨巨猿的牙齿大小时代演化趋势,同时提出存在的问题。

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 in Liucheng specimens which show a large variation in tooth size, and how sex Gigantopithecus attributed to the tooth size variation observed. of Gigantothecus co-existed ratio or sex dimorphism of