The effect of animal herding practices on the diversity of human stable isotope values in North Central Asia

Abstract

Human isotopic values from North Central Asia vary not only chronologically, but also spatially, which likely points to the exploitation of different resources for the subsistence. We argue that observed differences in the human isotopic ratios across North Central Asia are directly related to the animal herding strategies, which in turn were influenced by the local environment and landscape features. This paper presents a collation of both new (n = 149) and previously published (n = 585) carbon and nitrogen isotopic values measured on human bone collagen dating from the Bronze Age to Medieval period Northern Central Asia. These data have allowed modeling human dietary variations in different ecotones and chronological periods of North Central Asia. Analysis of isotopic values of various domestic herbivore species demonstrated that horses, cattle, and sheep/goats in North Central Asia tend to exhibit different isotopic signatures. The strong regional variations, particularly evident in δ13C values across North Central Asia from Bronze to Middle Ages tend to reflect the scale of C4 crop consumption by humans. However, they can also be related to the differences in the exploited herding strategies, such as the focus on cattle, horses or caprines husbandry as well as vertical transhumance pastoralism.