陕西潼关南寨子遗址人口的平均预期寿命与死亡模式

Average life expectance and mortality pattern at Nanzhaizi archaeological site,Tongguan,Shaanxi Province

作为社会存在和发展的基础和主体,人口因素在人类文明发展中起着重要作用。我们通过编制生命表,对陕西潼关南寨子遗址4个墓葬出土的人骨进行古人口学分析,计算出关中平原东部地区仰韶文化中期人口的平均预期寿命为27.8岁,高出我国西北、东北地区和太湖流域新石器时期的人口平均预期寿命约8岁,而与山东沿海地区大汶口文化时期的王因遗址较为接近。这可能与本区中全新世较大暖期东亚夏季风主导下的较为适宜的气候条件和农业社会较高的经济状况有关。分析发现南寨子遗址男性的平均预期寿命显著高于女性,符合史前人口的普遍规律。我们的研究表明育龄妇女围产期较低的护理条件是造成这一现象的主要原因。

Population played a pivotal role in the emergence and eomplexification of human society. As a primary knowledge base, human skeletal remains preserved in the graves of archaeological sites can open a window into the relationship between prehistoric demographical and cultural processes. Previous studies in northwestern and northeastern China revealed that the average life expectancy and mortality pattern of Neolithic people were totally different from modern human population. However, little is known about such demographical information on the Guanzhong Plain. Here we analyze a total of 18 human skeletons excavated from four graves at Nanzhaizi archaeological site about 0.6 km southeast of Tongguan, Shaanxi Province. The life table method is used to calculate the average life expectance and survival probability. It is a descriptive analytic method that represents the full life processes of a local biological population. Our results indicate that the average life expectance at this site is about 27.8 years, generally higher than that in northwestern and northeastern China as well as in Taihu area, but very close to that on the coast of Shandong Province. This high life expectance is most likely due to the optimal climatic and socio-economic conditions during the middle Holocene. Our results also reveal a sexual difference in the average life expectance. Specifically, the life expectance of male is slightly higher than that of female at childbearing age. This appears to be a common demographical phenomenon in prehistoric population. A closer look at the survival curves of both male and female suggest that the high mortality rate due to the poor perinatal care is the key reason for this phenomenon.