THE EVOLUTION OF HUMANKIND IN CHINA
Wu Xinzhi (Institute of Vertebrate Paleontology and Paleoanthropology, Academia Sinica, Beijing 100044)
Many fossils of Homo erectus and Homo sapiens have been found in China. The main results from different chronometric techniques are shown in a table of the present paper. This paper deals with human evolution in China in six aspects. I. There are common characteristics among human fossils in China. They are: the antero-lateral surface of the fronto-sphenoidal process of zygomatic bone facing more forward, the contour of the lower margin of the zygomatic process of maxilla, the high position of the part joining it with the maxillary body, more obtuse zygo-maxillary angle, flat nasal region, lower face, the contour of the suture between frontal bone and the interorbital bones approximating to a horizontal curve, founded infero-lateral orbital margin, sagittal keeling, Inca bone, shovel shaped upper incisor. II. The morphology of the human fossils in China shows almost similar evolutionary trend as those of the other part of the world. But not all of the changes are synchronous with the chronological sequence. For instance, the cranial bones of Homo erectus from Hexian is thicker than that of ZKD, those from Xujiayao are much thicker than those from Yinkou, the postorbital constriction in Hexian specimen is much less evident than those in Homo erectus of ZKD; Maba skull is more exaggerated than Dali with regard to this feature. These phenomenon may be explained in different ways. For instance, there might be different small populations, in which the development of various features might have different evolutionary speed. The various features of each specimen are not exactly the average status of the subpopulation it belongs. III. Mosaic phenomenon of morphology. Many possible autapomorphic features of Homo erectus have been suggested by various authors. Among these, several features are worthy to be discussed on the basis of Chinese fossils. 1, Thick vault bones: the average thicknesses of Dali and Xujiayao specimens are similar to that of the Peking Man. At certain parts such as parietal tubercle, Dali and Xujiayao specimens are even thicker than that of the Peking Man. 2, Pronounced postorbital constriction: it presents in Maba skull but very weak in that of Homo erectus of Hexian. 3, Frontal sagittal keeling: it is present on Dali, Yinkou and Maba early Homo sapiens skulls 4, Sharply angulated occipital: it appears on Dali and Yinkou skulls. 5, Prominent angular torus at mastoid angle of parietal bone: it appears on Dali skull. 6, Low temporal squama, it does not present in Hexian Homo erectus skull. The mosaic coexistence of the possible Homo erectus autapomorphic features with the features usually belonging to Homo sapiens in the same specimen indicates that in China, the Homo sapiens had been evolved from Homo erectus. All of the facts mentioned above supports the continuous evolutionary hypothesis of humankind in China. IV. Paleocultural evidence supporting this hypothesis. V. Gene exchange with other parts of the world and the dispersal of the modern humans to neighbouring regions. VI. Short comment on the newly found Tertiary large hominoid fossils in Yunnan. The hominoids unearthed from Hudieliangzi and Baozidongqing of Yuanmou, Yunnan are very close in morphology and date. To consider them belonging to the same genus as that for Lufeng large hominoid is much more reasonable than to propose a new genus (Sinopithecus) and to coin a new species: Homo orientalis.