Monastic Diets and Aquatic Species: Examining Potential Fish Consumption at the Ghazali Monastery, Sudan Through Stable Isotope Analysis of Sulphur

Abstract

Stable isotope analysis can be applied in bioarchaeological contexts as a tool to assess paleodiet as this technique relies on naturally occurring differences in isotopic values in different food sources and environments. Previous research has been conducted to assess possible dietary composition of the monastic inhabitants of at the medieval Makurian site of Ghazali (ca. 680-1275 CE), Nubia using stable isotope analyses of carbon (δ13C) and nitrogen (δ15N) on bone collagen of its monastic inhabitants. This showed a varied diet evidently comprising of both terrestrial plants and animals. Additionally, δ15N values observed in five individuals suggest potential aquatic species consumption in conjunction with terrestrial animal protein. However, no remains of aquatic species were identified during excavations at Ghazali, and little aquatic species were identified at other Makurian sites. This lack of evident aquatic species (e.g. fish) consumption at Ghazali brings forth numerous questions surrounding dietary practices both at Ghazali and within the broader region of similar Makurian monasteries.

This research utilized stable isotope analysis of sulphur (δ34S) on human bone collagen in conjunction with previously presented δ15N values, in tandem with existing textual and bioarchaeological evidence from Egypt and Byzantium, to determine the presence or absence of fish in the diet of the monastic inhabitants at Ghazali. The sample consisted of 20 individuals from Cemetery 2, where 18 of these individuals were male monks. Analysis of δ34S, when coupled with previous δ15N values, revealed that four of these individuals showed evidence of possible fish consumption alongside terrestrial animal protein consumption.