1. School of Psychology and Neuroscience, University of St Andrews, St Andrews KY16 9JP, UK
2. Department of Anthropology, Durham University, Durham DH1 3LE, UK
3. Messerli Research Institute, University of Veterinary Medicine Vienna Medical University of Vienna, University of Vienna, Vienna 1210, Austria
4. School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen AB24 3FX, UK
5. Division of Psychology, University of Stirling, Stirling FK9 4LA, UK
6. Faculty of Social Sciences and Public Policy, School of Education, Communication and Society, King's College London, London WC2R 2LS, UK
7. Department of Comparative Cultural Psychology, Max Planck Institute for Evolutionary Anthropology, Leipzig 04103, Germany
8. Department of Psychology, University of Portsmouth, Portsmouth PO1 2UP, UK