1. Henry Wellcome Ancient Biomolecules Centre, University of Oxford, Department of Zoology, South Parks Road OX1 3PS, UK.
2. Department of Archaeology, University of Durham, South Road, Durham DH1 3L, UK.
3. Department of Archaeology, University of Sheffield, West Street, Sheffield S1 4ET, UK.
4. Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences and Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala Biomedical Center, Box 597, SE-75124 Uppsala, Sweden.
5. Department of Anthropology and Allan Wilson Centre for Molecular Ecology and Evolution, University of Auckland, P.B. 92019, Auckland, New Zealand.