1. Department of Biological Sciences, Columbia University, New York, United States
2. Department of Biology, Stanford University, Stanford, United States
3. Department of Genetics, Stanford University, Stanford, United States
4. Lundbeck GeoGenetics Centre, Department of Biology, University of Copenhagen, Copenhagen, Denmark
5. Department of Anthropology, University of California, Davis, Davis, United States
6. Howard Hughes Medical Institute, Stanford University, Stanford, United States
7. Center for Population Biology, University of California, Davis, Davis, United States
8. Department of Evolution and Ecology, University of California, Davis, Davis, United States