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.
Wildebeest
The black wildebeest has been classified as a least-concern species by the International Union for Conservation of Nature in the "IUCN Red List". The populations of this species are on an increase. Now, more than 18,000 individuals are believed to remain, 7,000 of which are in Namibia, outside their natural range, and where it is farmed. Around 80% of the wildebeest occurs in private areas, while the other 20% is confined in protected areas. Its introduction into Namibia has been a success and numbers have increased substantially there from 150 in 1982 to 7,000 in 1992.
The blue wildebeest has also been rated as of least concern. The population trend is stable, and their numbers are estimated to be around 1,500,000 – mainly due to the increase of the populations in Serengeti National Park (Tanzania) to 1,300,000. However, the numbers of one of the subspecies, the eastern white-bearded wildebeest ("C. t. albojubatus") have seen a steep decline. Population density ranges from 0.15/km. in Hwange and Etosha National Parks to 35/km in Ngorongoro Conservation Area and Serengeti National Park.