论文部分内容阅读
一般认为东亚大陆更新世早期人类化石代表最早一批由非洲扩散来的人类.古人类学界对这些人类化石的形态特征及分类地位一直存在争议.采用几何形态测量方法对在湖北建始发现的3枚更新世早期人类牙齿,以及257枚非洲、欧洲和亚洲不同时代古人类和现代人类牙齿齿冠形状进行了对比分析.结果显示这三类牙齿的齿冠轮廓、对称性以及齿尖排列在化石人类与现代人类之间具有明显的差别.包括南方古猿、非洲早期人属和亚洲更新世古人类在内的多数化石人类P3齿冠轮廓明显不对称,咬合面轮廓呈弯曲的长椭圆形;M1咬合面轮廓对称,接近长方形,无明显齿尖突出;M1齿冠呈后尖和次尖略突起,原尖和内尖不显的非对称形状.与此相对,现代中国人和部分欧洲更新世晚期人类P3齿冠呈颊侧宽,舌侧窄的对称轮廓;M1齿冠形状明显不对称,舌侧齿尖向远中方向偏移,尤其以次尖突出显著;M1齿冠轮廓略呈对称的圆形.南方古猿齿冠形状变异范围较大,而亚洲古人类在牙齿形态区域分布比较集中.建始人3枚牙齿齿冠轮廓、对称性以及齿尖排列与亚洲更新世早期和中期古人类的同类牙齿形状接近.未发现建始人牙齿齿冠形状明显不同于其它中国直立人,而与南方古猿及非洲早期人属成员特别相似的证据.
It is generally believed that the earliest Pleistocene human fossils in East Asia represented the first group of humans that had spread from Africa.Ancient anthropological scholars have been controversial about the morphological characteristics and the taxonomic status of these human fossils.Through the geometrical measurement method, Early Pleistocene human teeth, as well as 257 different ages in Africa, Europe and Asia of ancient human and modern human tooth crown shape were compared.Results show that these three types of tooth crown contour, symmetry and tip arranged in fossil humans And modern humans have obvious differences between the majority of fossil human P3 crown including Australopithecus, Early African and Asian Pleistocene human beings significantly asymmetric profile, occlusal surface contour was curved oval; M1 occlusion The surface profile is symmetrical, nearly rectangular, with no prominent tooth tips; M1 tooth crowns are apexes and sub-sharp protrusions, asymmetric shapes with no obvious apical and inner tips. In contrast, modern Chinese and some late Pleistocene in Europe Human P3 tooth crown was buccal wide, lingual narrow symmetrical contour; M1 tooth crown shape was significantly asymmetric, lingual tooth tip shift to the far direction, especially in the second The tip of M1 tooth crown is slightly symmetrical, the variation range of the crown shape of the Australopithecus australis is larger, while that of the Asian ancient humans is more concentrated in the tooth shape area. The tip arrangement is close to the shape of the same type of ancients in the early and mid-Pleistocene Asia, with no evidence that the tooth shape of the toothbrush in Jianshi was significantly different from that of other Chinese Homo erectus, with evidence of particular resemblance to members of the Southern Australopithecus and early African genera.