Isotopic Insight Into the Human Diet at Qareh Tepe, Iran, During the Iron Age (c. 1200–750 bce)

Abstract

The period preceding early state formation in Iran (i.e., Early Iron Age) is frequently associated with the prevalence of mobile pastoralists. The analysis of stable carbon and nitrogen isotope ratios of human and animal collagen from Qareh Tepe (c. 1200–750 cal. bc) in Qazvin Plain was performed to understand local subsistence strategy and especially to distinguish between mobile herding and stationary farming, which is crucial in understanding pathways leading to the centralization of power in that time. In total, 53 human dentin samples and 30 animal bone and dentin samples were analyzed. The comparative data come from four other Iranian sites of variable chronology: Sagzabad, Zagheh, Tepe Pardis, and Tepe Hissar. Standard methods of collagen extraction and isotope ratio mass spectrometry were applied. People from Qareh Tepe were characterized by very high δ¹⁵N values, clearly higher than at all other sites. There was a significant difference between the sexes, with males having more negative δ¹³C values. In combined faunal data from the Qazvin Plain, suids composed a separate group, whereas all the herbivores showed a clear correlation between δ¹⁵N and δ¹³C values. Elevated nitrogen isotopic values in humans from Qareh Tepe may be explained by a high level of manuring with animal dung, forced by an increased population size in the limited space of the alluvial fan. The research reveals that, at the dawn of the Median state, the Central Plateau of Iran was most likely not inhabited by nomadic pastoralists but rather by agropastoral communities that knew how to make the best use of limited environmental resources.