Sulphur Isotope Ratios of Archaeological Human Collagen as a Mobility Indicator

Abstract

Sulphur isotope ratios (34S/32S, δ34S) in human bone collagen can be used as an indicator of both mobility and migration. As collagen continuously remodels, it can be used to look at mobility in the later life stages of humans and other mammals. However, as sulphur is a minor component of mammalian collagen, it can be difficult to measure, so there are relatively few published sulphur isotope mobility studies. Sulphur is also a dietary indicator and distinguishing between sulphur isotope values that indicate mobility or differing diets can be challenging. In this paper, I outline the potential uses of sulphur in archaeological research with an emphasis on its use as a mobility indicator. Despite the potential difficulties in measurements and interpretation, sulphur isotopes can play an important role in understanding human mobility in the past, especially now with advances in mass spectrometry making sulphur measurements more accessible. Moving forward, combining bone collagen sulphur isotope values with the more widely applied mobility indicators strontium and oxygen in tooth enamel, which record mobility in childhood, may allow us to produce a more comprehensive picture of an individual’s mobility over the duration of their lifetime.