1. Centre for Molecular Microbiology and Infectious Diseases, Imperial College of Science, Technology and Medicine, London SW7 2AZ, UK
2. School of Geography, Archaeology and Palaeoecology, Queen's University Belfast, Belfast BT7 1NN, UK
3. Department of Genetics, Institute of Child Health, University College London, London WC1N 1EH, UK
4. Peter the Great Museum of Anthropology and Ethnography (Kunstkamera), 3 University Embankment, St Petersburg 199034, Russia