Stable isotopes
Stable isotopes have a number of uses in archaeology. The concentrations of C-, N- and S-isotopes in human bone collagen can provide basic information on diet, such as the relative importance of terrestrial versus aquatic food sources. In practice, however, applications of dietary tracing using stable isotopes in the Scottish Mesolithic have been severely limited by the scarcity of human remains. No formal burials are known from Mesolithic sites, and the only dietary stable isotope results available are for disarticulated human remains from shell middens on the Isle of Oronsay (Richards and Mellars 1998; Richards and Sheridan 2000; Milner and Craig 2009). Sr- and O-isotopes in human bone/teeth can be used as tracers of population movement, but again Mesolithic applications in Scotland are constrained by the lack of human remains. O-isotope analysis can also be used to investigate the season of exploitation of fish and shellfish found in archaeological sites. While there have been some notable applications at Mesolithic sites around the Atlantic and Mediterranean coasts of Europe (e.g. Mannino et al. 2003; Colonese et al. 2009), the technique has hardly been used at all in Scotland (in spite of the abundance of suitable material); instead seasonality studies have relied on growth-line analysis of cockle shells (Deith 1983) or metrical analysis of fish otoliths (Mellars and Wilkinson 1980).