Strontium and nitrogen isotopic evidence of food import to Tell Ashara–Terqa, a Bronze Age city on the Euphrates, Syria

Abstract

Strontium stable isotope values (87Sr/86Sr) have been measured in tooth enamel samples representing 11 Bronze Age individuals buried at Tell Ashara–Terqa, a major archaeological site in the middle Euphrates valley, eastern Syria. For all analysed individuals, δ15N and δ13C values for dentin collagen were also available. No 87Sr/86Sr value exceeds the local environmental range, so there is no evidence of long‐distance migration. Observed statistically significant negative correlation between 87Sr/86Sr and δ15N values suggests that some food consumed by the local population was imported from areas with a much higher precipitation (lower δ15N) and a different geological background (higher 87Sr/86Sr), which is consistent with textual evidence of cereal transportation from farming areas north to Tell Ashara.

Identifying food provenience using Sr/Ca ratio in human enamel

“…Therefore, the low average Sr/Ca value in the Modern Islamic subset is not primarily the consequence of a diet rich in animal‐derived food, but it reflects the broader use of the dry steppe beyond the Euphrates valley as pasture, with much lower Sr concentrations in local soils and therefore also in plants. Also relatively low Sr/Ca values in the Shakkanakku period and in some individuals from the Old Babylonian period are consistent with the available written sources that report not only cereal importation from the north, which is visible also in the distribution of δ 15 N and 87 Sr/ 86 Sr data during that time (Sołtysiak 2019), but also a dimorphic subsistence model parallel to the Bedouin one, with mobile herders beyond the valley, enclosed in a farming society (Rowton 1974). In the period when population size was relatively large, using resources of different origin was a necessity, and all available lines of evidence suggest that a considerable part of food consumed in that time was produced beyond the Euphrates valley.…”

“…Food transportation from places approximately 400 km away from Mari is referred to in historical texts (Michel 1996; Durand 2011). Moreover, the presence of individuals at Tell Ashara with relatively low δ 15 N values and 87 Sr/ 86 Sr values that slightly deviate from the local range indicates that some inhabitants of the site may have consumed more food imported from the north (with a lower δ 15 N because of higher humidity and more extensive agriculture as well as a slightly different local 87 Sr/ 86 Sr signature) than the others (Sołtysiak 2019). At the same time, the exchange of products between farmers living in the valley and herders operating in the steppes beyond the valley is also attested in the written sources (Rowton 1974).…”

“…The advantage of these sites is not only their location but also the presence of textual evidence enabling insights into food provenience, especially for the first quarter of the second millennium bce (Michel 2009), as well as data on stable C and N isotopes (Sołtysiak and Schutkowski 2018) with limited data on Sr isotopes. All this specifically suggests that food imports from dry farming areas to the Euphrates valley may have been significant at least when the regional state of Mari controlled large parts of Upper Mesopotamia between c .2600 and 1750 bce (Sołtysiak 2019). Therefore, this is a good point of departure to investigate the possibility of using the Sr/Ca ratio in human enamel as a proxy for food provenience.…”

Who were the Hyksos? Challenging traditional narratives using strontium isotope (87Sr/86Sr) analysis of human remains from ancient Egypt

“…Strontium isotope ( 87 Sr/ 86 Sr) analysis of human tissues provides insight into residential mobility and origin on the individual level, allowing extrapolations into largescale socio-political dynamics [36][37][38][39][40]. Multiple paleomobility studies have utilized 87 Sr/ 86 Sr on human dental enamel to identify non-locals in Egyptian and Sudanese contexts along the Nile Valley [41][42][43][44][45], although none have been conducted on humans from the Nile Delta region.…”

Jordanian migration and mobility in the Middle Bronze Age (ca. 2100–1550 BCE) at Pella

“…Strontium isotope ( 87 Sr/ 86 Sr) analysis of human tissues provides insight into residential mobility and origin on the individual level, allowing extrapolations into large‐scale socio‐political dynamics (Sołtysiak, 2019; Stantis & Schutkowski, 2019). Interpretation of strontium isotope analysis rests on the assumption that an individual's body tissues will reflect the 87 Sr/ 86 Sr values of the underlying geology in which they lived when these tissues were forming, with no appreciable fractionation across trophic levels or in metabolic processes (Lewis et al, 2017).…”