Early emergence and development of pastoralism in Gan-Qing region from the perspective of isotopes

Human subsistence strategies and husbandry practices for sheep, goats, and cattle in the Gan-Qing region between the late Neolithic and Bronze ages remain ambiguous. This study sought to uncover this history by analyzing animal assemblages and reconstructing animal dietary intake using faunal remains derived from three settlement sites in the region and their isotopic data. We isotopically analyzed a total of 387 animal samples and found that from 5300 to 4900 BP and 4100 to 3600 BP pigs were free-range and/or raised at inhabitation sites and dogs may have been free-range and may have hunted with humans and/or remained close to habitation sites. These flexible ways of raising pigs and dogs may have enabled inhabitants to make full use of natural resources and to save millet fodder. Meanwhile, sheep, goats, and cattle were mainly herded in grasslands during the Bronze Age, with their diets dominated by C 3 and mixed C 3 /C 4 plant consumption, which differs notably from the husbandry practice in the Central Plains. In addition, the δ 15 N values of wild herbivorous animals in arid regions were higher than those in semi-arid regions, suggesting that animal δ 15 N values may vary with aridity. This paper not only sheds light on the progress of and plausible reasons for pastoralist and mobile pastoralist practice in the Gan-Qing region during these periods but, in doing so, also provides a nitrogen baseline for reconstructing human diets in the Gan-Qing region.