关键词: 中国;古人类;进化连续性

Abstract: Through analysis of morphological features, this article discusses some problems concerning the methodology of thinking in the study of human evolution and provides new evidence to support the Multiregional evolution model as follows. 1) Do not neglect the role played by gene exchange in the formation of certain features of recent skulls, such as orbital shape, the form of infero-lateral margin of the orbit, and the contour composed of the fronto-nasal and fronto-maxillary sutures. These features in recent East Asian skulls are different from those in Pleistocene specimens in China, which indicates that the continuity of them in East Asia has not persisted to nowadays, but does not exclude the continuity of them in the Pleistocene. The difference between recent and Pleistocene skulls in morphological features may be caused by genetic drift andΠor gene exchange between East Asia and outside in the Holocene and Late Pleistocene. 2) Features not unique for a region, are considered as not deserving to be the evidence for continuity of human evolution in that region by some scholars. But it is probable that common ancestry and gene flow between ancient populations of different regions should have caused many features not unique in many regions. Common features of Pleistocene skulls in China are not necessarily unique in this region. The fact that some common features in Pleistocene China also exist in other regions does not weaken the value of them in supporting the evolutionary continuity in East Asia. Discontinuity in evolutionary process would make the earlier population different from the later ones, or there would be no common features shared by them. 3) Do not forget that human evolution is a dynamic process where there was a tendency towards more gracile status for various morphological features throughout human evolution, and various features could experience changes due to the effect of genetic processes such as gene exchange with neighboring populations etc. So it is not reasonable to expect morphological features of the descendants to be completely similar to those of their ancestors in strength and frequency of trait occurrence. The weaknesses of the basal tubercle and the curvature on the labial surface in recent East Asian human upper incisors does not indicate that shovel-shaped incisors could not be one of the features supporting the continuity of human evolution in this region. The decreasing frequencies of chignon and suprainiac fossa in Europeans from Neandertal to modern humans are part of the dynamic process. Cranial indices of Late Paleolithic Liujiang, Ziyang and Lijiang skulls are 75.1, 77.4, and 84.4 respectively, whereas those of three Upper Cave skulls are 70.1, 69.4 and 71.2 respectively. The chignon exists in the former three skulls with their shorter vaults and is absent in the latter with their characteristic long skulls. These facts disprove the opinion that the chignon is most likely caused by a more rapid“posterior growth of the cerebral hemispheres relative to formation of the cranial vault bones”. 4) Do not misinterpret the observation of specimens and opinion of the opposing side. For instance , in the paragraph discussing“Facial size is a vague character”, Lieberman wrote,“the four relatively complete archaic fossils with faces from North China (Dali, Jinniushan, and YunxianⅠandⅡ) are somewhat distorted. ” (p.172) . He hinted that the faces of these skulls are not short as being proposed by anthropologists who advocate the Multiregional model as one of the evidence of continuity. But in fact, although skulls from these sites had experienced different degrees of distortion, any correct reconstruction will not change the status that their upper faces are short. Furthermore, the face of new middle Pleistocene skull from Nanjing is definitely short. 5) The contrast between the presence of mid-sagittal keeling, mandibular oxostosis, pinched nasal saddle and agenesis of third molar in recent East Asians, and their absence in recent African skulls fit better with the Multiregional model rather than the Recent Out of Africa model. The fossil record suggests that mid-sagittal keeling and mandibular oxostosis existing in recent East Asians may derive from Homo erectus of Beijing; the pinched nasal saddle may be traced to Maba early H. sapiens skull and Upper Cave skull 101; and the agenesis of the third molar may be related to the Homo erectus mandible from Lantian and Upper Pleistocene skull from Liujiang. To consider the origin of these features in recent East Asians as effects of genetic drift during the dispersal out of Africa is less convincible.

Key words: Evolutionary continuity; Fossil humans; China