中国第四纪人类牙齿大小的演化及其意义

对第四纪中国境内人类牙齿大小变化特点的分析及与世界其它地区人类牙齿测量数据的对比分析显示,从直立人到现代人,中国境内人类牙齿尺寸呈缩小变化,但在具体表现特点上,中国古人类牙齿尺寸的演化具有与世界其它地区人类不同的特点。作者认为,这些特点反映了中国古人类演化过程中生存环境和文化发展的特点,提示中国乃至东亚地区人类演化及文化发展的独特性。本文对其在东亚地区人类演化上的意义进行了讨论。

THE EVOLUTION OF TOOTH SIZE OF QUATERNARY HUMANS IN CHINA

The purpose of thes paper is to study the evolution of tooth size of Quaternaryhoumans in China. Total of 307 fossil teeth, which represent most of dental specimensof Homo erectus, early Homo sapeins and fare Homo sapeins found in China. wereused for metric analyses in Present study, The dental metric data used for comparativeanalyses include humans of Neolithic, Bronze age and modem bine Periods of China.The dental metric data of Europeans from the bine periods of early Neanderthal tillrecent and early modem human of Qafzeh recovered in Western Asia were also used.The measurements of mesial-distal (MD) and buccal-lingual(BL) tooth crown diameterswere used. With the two measurements, different kinds of cross-sectional areas werecalculated for statistical analyses.After that, from lare Homo sapiens till modem Chinese the speeds of tooth sizereduction went down and the tooth size came into the range of that of modernChinese gradually. During this bine periods, only 6% of tooth size reduced. Also therates of tooth size reduction from late Homo sap lens till modem Chinese reducedgradually. From late Homo sapiens to Neolithic the tooth size reduction is 3.7%,while from Neolithic to modem Chinese, the reduction rate is only 2.4%. Comparedwith the changes of tooth sizes of Late Pleistocene and Holocene Europeans, thepatterns of tooth size reduction of Chinese are quite different from those of Europeans.The main differences include earlier aPPearance of sharp tooth size reduction, highvariations of the speed of tooth size reduction and smaller scope of overall dentalreduction. In humans of Europe, the rapid tooth size reduction happened tansitionperiod from UPper Paleolithic to Neolithic. Also, In Europeans, the tooth sizereduction since the Late Pleistocene went with steady and regular rare. In comparisonwith the tooth size of early modem human of Qafzeh in Western Asia, all kinds oftooth area data of Qafzeh exceed those of the people of Late Pleistocene in China.The Summary Tooth Size of Qafzeh is 1 509.4 mm2, While that of late Homo sapiensof China is 1 282.8mm2. In addition of this, the tooth sizes of early modern hrmansin Western Asia are obviously bigger than those of Upper Paleolithic Europeans andare closer to those of Neanderthals in Europe. The Stunmary Tooth Sizes of lateNeanderthals and Upper Paleolithic Europeans in Europe are 1 448. 1 mm2 and 1 350.1mm2 respectively, which are colser to that of Qafzeh. So the tooth sizes of Qafzehexceed the ranges of tooth sizes of anatomically modern humans in China and Europegreatly. The author believes the tooth size of the hUmans in Qafzeh of Western Asia,who were regarded as the earnest anatomically modem humans and the direct ancestorof the modem humans in Europe and Asia, do not show any characteristics ofmodem human. There is no enough evidence for the idea to put the early modernhumans in Western Asia in the place of the direct ancestor of the modem humans inEurasia.The author believes that the expression patterns and evolutionary trends of toothmeasurements of the humans in China indicate at least in the past hundreds ofthousand years, they have marked regularity and unique style, which are especiallyobvious in the bine periods of Late Pleistocene and Holocene. This regularity andunique style suggest there are evolutionary continuity and genetic links between thehumans of different bine periods in China. The unique style of cultural developmentduring the human evolution of China is also revealed. The evolutionary continuity andunique style of cultural development is the results of human evolution of China inrelative isolation and independently. The author proposes that the findings of presentstudy can be taken as the new evidence to support the regional continuity theory ofhuman evolution in China. The local origin of Mongoloid populations in East Asia isthe best explanation to the findings of present study.The author believes that according to the evidence available, the tooth sizes andtheir change patterns of Chinese humans, especially the similarities between Homoerec