Blue wildebeest
This species of wildebeest seems to have evolved around 2.5 million years ago. The black wildebeest is believed to have diverged from the blue wildebeest to become a distinct species around a million years ago, in the mid- to late Pleistocene. Fossil evidence suggests that blue wildebeest were quite common in the Cradle of Humankind in the past. Apart from eastern Africa, fossils are commonly found in Elandsfontein, Cornelia, and Florisbad.
Black wildebeest
The black wildebeest is particularly susceptible to anthrax, and rare and widely scattered outbreaks have been recorded and have proved deadly. Ataxia related to myelopathy and low copper concentrations in the liver have also been seen in the black wildebeest. Heartwater ("Ehrlichia ruminantium") is a tick-borne rickettsial disease that affects the black wildebeest, and as the blue wildebeest is fatally affected by rinderpest and foot-and-mouth disease, it is also likely to be susceptible to these. Malignant catarrhal fever is a fatal disease of domestic cattle caused by a gammaherpesvirus. Like the blue wildebeest, the black wildebeest seems to act as a reservoir for the virus and all animals are carriers, being persistently infected, but showing no symptoms. The virus is transmitted from mother to calf during the gestation period or soon after birth.