1. School of Psychology, Centre for Research in Animal Behaviour, University of Exeter, Exeter EX4 4QG, UK
2. Research Centre for Anthropology and Health, Department of Life Sciences, University of Coimbra, 3000-456 Coimbra, Portugal
3. Department of Applied Mathematics and Computer Science, Technical University of Denmark, DK-2800, Kongens Lyngby, Denmark
4. Center for Evolution and Medicine, Arizona State University, Arizona, AZ 85281, USA
5. Department of Neuroscience, University of Pennsylvania, PA 19104, USA
6. Department of Psychology, University of Pennsylvania, PA 19104, USA
7. Department of Marketing, University of Pennsylvania, PA 19104, USA
8. Department of Anthropology, New York University, New York, NY 10003, USA
9. School of Life Sciences, Arizona State University, Arizona, AZ 85281, USA
10. School for Human Evolution and Social Change, Arizona State University, Arizona, AZ 85281, USA