Human subsistence strategy at Liuzhuang site, Henan, China during the proto-Shang culture (~2000-1600 BC) by stable isotopic analysis

摘要

Since the discovery of the proto-Shang culture, created mostly by ancestors of the Shang clan from the late Neolithic Age to the early Shang period (~2000-1600 BC), the subsistence strategy and lifestyle of humans in China during their movement southwards have been a great focus. Chinese literature and archaeological findings suggest that the proto-Shang societies were composed of different cultural groups and had various subsistence strategies. For example, at the Liuzhuang site, three types of burials, i.e., stone coffin, wooden coffin and earthen shaft-pit, are found. The wooden coffin and earthen shaft-pit burials had been adopted locally in the Central Plains since the Neolithic Age while the stone coffin burials were usually used by people living in Northeast China and had never been found in the Central Plains before. In this study, stable carbon and nitrogen isotopic analyses were performed on human bones from the Liuzhuang site and animal bones from Zhangdeng site in Henan province, China to determine whether different social groups had various accesses to food resources and whether their dietary difference was related to inequality in social status. Humans have mean δ~(13)C and δ~(15)N values of -7.6 ± 0.6‰ and 9.6 ± 1.0‰ (n = 19) respectively, which strongly indicates that humans rely primarily on C_4-based food. The main contribution of C_4-based food in their diet is from millet agriculture or animals that consume millet by-products. The isotopic spacing of carbon and nitrogen isotopic values between pigs and humans, between dogs and humans, and between cattle and humans, all imply that these animals were the main meat resources for humans. Surprisingly, the δ~(13)C values and δ~(15)N values of humans with different types of burials are quite close, indicating that they had equal access to food resources. This result suggests that the proto-Shang humans had adapted to the local subsistence strategy, and the local cultural factors in the Central Plains were very well integrated into proto-Shang culture.