1. Department of Anatomy and Physiology, University of Pretoria, Onderstepoort, South Africa
2. Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa
3. Department of Biology and Earth Science, Otterbein University, Westerville, Ohio, United States
4. Department of the US Army Research Office, Research Triangle Park, North Carolina, United States