1. University Program in Ecology, Duke University, Durham, NC, USA
2. Department of Evolutionary Anthropology, Duke University, Durham, NC, USA
3. Kalahari Research Trust, Kuruman River Reserve, Van Zylsrus, Northern Cape, South Africa
4. Department of Biological Sciences, University of Alabama, Tuscaloosa, AL, USA
5. Department of Zoology, University of Cambridge, Cambridge, UK
6. Mammal Research Institute, University of Pretoria, Pretoria, South Africa
7. Department of Biology, Duke University, Durham, NC, USA