The evolutionary time span required to produce specialist grazers such as wildebeest is considered in relation to the effect on the species of rapid, man-induced changes in Etosha such as fencing, constructed water points and abnormal levels of disease and predation. Basic environmental requirements for a viable wildebeest population are examined and related to the situation presently existing in Etosha. Keywords: Adapt to survive, African ungulates, Biotic zones, Climatic factors, Disease, Ecological success, Eocene-Oligocene, Evolutionary history, Food, Microbial-mammal symbiosis, Nitrogenous substances, Predation, Reproduction, Terrestrial herbivore biology, Thermoregulation, Topography, Water requirements