For the first time, a 4,000-year dietary record from the central-eastern Eurasian Steppe reveals that ancient populations across six regions—from Xinjiang to Mongolia—shifted their diets in near-perfect synchrony, adding a new dimension to our understanding of human-environment interaction in this vast region.
This study are led by Dr. Wei Wang from Nanjing University of Information Science and Technology and Professor Chengbang An from Fudan University, in collaboration with Dr. Futao Duan from Nanjing University of Information Science and Technology and Associate Research Curator Xuemei Yan from the Institute of Cultural Relics and Archaeology in Xinjiang. The team conducted carbon and nitrogen stable isotope analysis on human and animal bones excavated from the Baiyanghe cemetery at the northern foothills of the Tianshan Mountains in Xinjiang, spanning from the Late Bronze Age to the Tang Dynasty. Combined with radiocarbon dating, this study provides the first systematic reconstruction of 4,000 years of dietary evolution in this region.
The research team further integrated the Baiyanghe data with nearly 1,500 published isotopic records from key regions across the central-eastern Eurasian Steppe, including the Minusinsk Basin, the Altai Mountains, central Kazakhstan, southeastern Central Asia, and central Mongolia. The results reveal that, despite differences in ecological and social-cultural environments, the dietary structures of populations across the central-eastern Eurasian Steppe exhibited a remarkably synchronized evolutionary trajectory: during the Bronze Age (5000-3000 BP), populations across the region predominantly consumed C 3 -based foods, including wheat, barley, and meat and dairy products from domesticated herbivores; from the Early Iron Age to the Han Dynasty (3000-2000 BP), the consumption of C 4 crops (primarily broomcorn millet) increased substantially, along with a marked rise in animal protein intake; during the Han-Tang period (2000–1000 BP), millet consumption declined significantly, and diets shifted back toward C 3 -based staples.
Notably, the comparison also revealed regional and social differences in dietary transitions: from the Early Iron Age to the Han Dynasty (3000-2000 BP), the Minusinsk Basin, southeastern Central Asia, and the northern Tianshan Mountains were high-intensity C 4 crop utilization zones, where millet had become a staple food for the majority; in contrast, central Kazakhstan, the Altai Mountains, and central Mongolia were limited-utilization zones, where millet consumption was largely restricted to elite strata and served as a symbol of social status. Data from the Baiyanghe cemetery further indicate that individuals buried with abundant grave goods or gold artifacts generally exhibited higher δ 15 N values, though exceptions exist, suggesting a correlation between social status and animal protein consumption that is not strictly deterministic.
Integrating paleoclimatic and archaeological evidence, the research team proposes that the dietary shift from the Bronze Age to the Early Iron Age–Han Dynasty was likely facilitated by a warm and humid climate that enhanced interregional exchange among pastoralist groups, while the dietary transition from the Han to the Jin-Tang periods was possibly driven by a cooling and drying climatic trend, together with advances in grain processing technology. This study provides critical empirical evidence for understanding human-environment interactions and the driving mechanisms behind large-scale dietary transitions in the Eurasian Steppe.
See the article:
Wang W, Duan F, Yan X, An C B. 2026. Diachronic dietary evolution from the Bronze Age to the Tang Dynasty in the central-eastern Eurasian steppe revealed by stable isotopes of the Baiyanghe cemetery, Xinjiang. Science China Earth Sciences, 69(6): 2102–2117, https://doi.org/10.1007/s11430-025-1861-y
Science China Earth Sciences