古骨胶原的氧同位素分析及其在先民迁徙研究中的应用

Oxygen isotope analysis of ancient bone collagen and its application in the study of human migration

古骨中的O同位素分析可以揭示先民和动物的饮用水来源,复原其所处的古环境,可为探索先民的来源地和迁徙状况提供重要的参考信息.选取中国商代都邑级别的郑州小双桥遗址出土的17例动物和先民骨骼,在C、N稳定同位素分析食物结构的基础上,利用O稳定同位素分析,对动物物种间δ18O值的差异状况与饮用水来源、代谢方式和饮食结构的关系,以及先民δ18O值的差异原因和身份进行了探讨.结果表明,不同种属动物骨胶原的δ18O值存在较大差异,并且这些差异与个体饮食中C3和C4食物比重的关系不大,更多地是受饮用水中δ18O值与新陈代谢方式(反刍和非反刍)的影响,反刍类动物明显高于非反刍类动物.此外,遗址中先民的δ18O值也有较大差别,表明这些先民生前可能至少来自2个区域,Ⅴ区丛葬坑H66中埋葬的先民相比Ⅸ区地层中的部分先民,来自于更接近海洋的地区.结合古文献和考古资料,推测Ⅴ区丛葬坑H66中埋葬的先民极有可能是东夷族人.

Oxygen isotope analysis of archaeological bone can provide information on the drinking water of animals and human ancestors and determine the possible conditions in their living environment. This provides important reference information for exploring the origin and migration of ancient humans. This study used bones from 17 ancient animal and human individuals unearthed from the Xiaoshuangqiao archaeological site（XSQS） for oxygen, carbon, and nitrogen isotope analysis. Together with the palaeodiet conditions reconstructed from carbon and nitrogen stable isotope analysis, we used the oxygen stable isotope measurements to determine the differences between the δ18O values of different species and explore the relationships of these values with drinking water, metabolism, and diet. In addition, the reasons for the different δ18O values among human ancestors and their identity were discussed. There was a large difference in collagen δ18O values between different species; we assumed this phenomenon was mainly caused by different sources of drinking water and methods of metabolism（ruminants and non-ruminants）, and had little to do with the dietary proportions of C3 and C4 food. The δ18O values of ruminant animals were significantly higher than those of non-ruminant animals. In addition, the δ18O values of human collagen were highly variable, suggesting that these individuals had lived in at least two regions. Specifically, the individuals buried in H66 of V District may have lived in an area closer to the ocean than did those buried in deposits in IX District. Combining our findings with historical literature and archaeological data, we speculate that the humans buried in the H66 gravel pit could be Dongyi people.