1. Department of Anthropology, University of California Santa Barbara, Santa Barbara, CA 93106, USA
2. School of Human Evolution and Social Change, Center for Evolution and Medicine, Arizona State University, Tempe, AZ 85287, USA
3. Institute for Advanced Study in Toulouse, Toulouse 31015, France
4. Economic Science Institute, Chapman University, Orange, CA 92866, USA
5. Department of Anthropology, Washington State University, Pullman, WA 99164, USA