Sulphur isotopes in palaeodietary studies: A review and results from a controlled feeding experiment

Recent advances in mass spectrometry now allow relatively routine measurements of sulphur isotopes (delta S-34) in small samples (>10 mg) of tissue from archaeological human, plant, and faunal samples. delta S-34 values of human and faunal bone collagen can indicate residence or migration and can provide palaeodietary information. Here we present a review of applications of sulphur isotopes to archaeological materials, and we also present preliminary results from one of the few controlled feeding experiments undertaken for sulphur isotopes. This study indicates that there is relatively little fractionation (-1%) between diet and body protein (keratin) delta S-34 values for modern horses on a protein adequate C-3 plant diet. In contrast, horses fed a possible low protein C-4 feed have a diet to hair fractionation of +4% that could be the result of the input of endogenous sulphur from the recycling of body proteins.