Multi-isotope analysis and the reconstruction of prey species palaeomigrations and palaeoecology

Abstract

This thesis explores the use of multi-element isotope analysis and intra-tooth sampling to reconstruct prey species ecology and biogeography. Modern caribou (Rangifer tarandus ssp.) and bison (Bison bison) from North America are used to assess the relationship between known lifetime movements and feeding habits, and those reconstructed through the stable isotope analysis of teeth and bone, including strontium (87Sr/86Sr), oxygen (d18O), carbon(d13C), nitrogen (d15N) and sulphur (d34S). Teeth (enamel and dentine) were sequentially-sampled in order to reconstruct time-series isotopic profiles at an intra- and inter-individual scale, allowing an assessment of the applicability of these methods to archaeological materials. The 87Sr/86Sr and d18O data indicate the clear potential for these methods to identify faunal movements, and to discern ranging behaviours from true migrations. d34S values of bone collagen compliment enamel 87Sr/86Sr data in the same individuals, and suggest the use of this approach for the identification of geographical origin.d13C and d15N from sequentially-sampled dentinal collagen allows the identification of some seasonal foraging behaviours, most notably winter lichen consumption in the caribou.

The same stable isotope and sampling techniques are then applied to fauna from the late Pleistocene site of Jonzac (Chez-Pinaud), France, in order to investigate the biogeography and feeding ecology of Middle Palaeolithic prey-species. The elevated d13C values in reindeer bone collagen compared to the other species indicates lichen feeding and the prevalence of this niche feeding behaviour in this ancestral species. The sequential-sampling and strontium isotope analysis of herbivore enamel from the site clearly demonstrates seasonal migratory behaviour in reindeer (Rangifer tarandus sp.), and allows the identification of a non-migratory taxon, bison (Bison sp.) This is the first such evidence for migration in Pleistocene reindeer, allowing greater insight into the palaeoecology of this prey animal, and the palaeoenvironment in which Neanderthals lived and hunted.