Functional differentiation of African grazing ruminants: an example of specialized adaptations to very small changes in diet

School of Biological and Conservation Sciences, University of KwaZulu-Natal, Private Bag X01, Scottsville 3209, South Africa Florisbad Quaternary Research, National Museum, Bloemfontein 9300, South Africa Centre for Environmental Management, Faculty of Natural and Agricultural Science, University of the Free State, Bloemfontein, 9300, South Africa Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurich, 8057, Switzerland Department of Archaeology, University of Cape Town, Private Bag, Rondebosch 7701, South Africa Department of Archaeological Sciences, Bradford University, Bradford BD7 1DP, UK Department of Anthropology, University of Colorado at Boulder, Boulder, CO 80309, South Africa