The first isotopic insight into the Bronze Age dietary transition in the area of present-day Czechia

To describe changes in diet and/or agricultural practices over the course of the Bronze Age on the territory of present-day Czechia, carbon (δ¹³C) and nitrogen (δ¹⁵N) isotopic values were measured in bone or tooth collagen from 103 humans and 30 animals, together with 8 samples of charred cereal grains. The dataset was divided into four subgroups according to geographical and chronological contexts: Early (2200–1500 BCE) vs. Late (1300–1020 BCE) Bronze Age, and Bohemia vs. Moravia.

Both carbon and nitrogen isotopic values showed statistically significant differences between the chronogeographic contexts. In accordance with archaeobotanical results, there was no significant input of millet in the Early Bronze Age sample (average human-faunal isotopic offsets of 0.5‰ for Bohemia and 1.3‰ for Moravia), whereas in the Late Bronze Age the significant input of millet is clearly documented (average human-faunal isotopic offsets of 3.9‰ for Bohemia and 5‰ for Moravia). The statistically significant difference between the two Late Bronze Age geographical units clearly shows that there was considerable variation in millet consumption across Czech territory.

The relatively low δ¹⁵N values observed in Late Bronze Age contexts (average human-faunal isotopic offsets of 1.9 ‰ for Bohemia and 2.4 ‰ for Moravia) may indicate a certain restriction of high-quality diet, namely animal products, in individuals exempted from the regular burial treatment of cremation.