the parents. It was formerly distributed throughout the western Kenyan highlands, between Lake Victoria and Mount Kenya, but is now believed to be restricted to the Lambwe Valley (south-west Kenya) and Laikipia and nearby regions of west-central Kenya. The Jackson's hartebeest does not have a clear taxonomic status. Like the form above, it is regarded as a hybrid between the Lelwel and Coke's hartebeest, and has a similar distribution. The African Antelope Database (1998) treats it as synonymous to the Lelwel hartebeest. From Lake Baringo to Mount Kenya, the Jackson's hartebeest significantly resembles the Lelwel hartebeest, whereas from Lake Victoria to the southern part of the Rift Valley it tends to be more like the Coke's hartebeest. Alcelaphus lelwel x swaynei : Also known as the Neumann's hartebeest, named after traveller and hunter Arthur Henry Neumann. This is considered to be a cross between the Lelwel hartebeest and Swayne's hartebeest. The face is longer than that of the Swayne's hartebeest. The colour of the coat is a golden brown, paler towards the underparts. The chin has a hint of black and the tail ends in a black tuft. Both sexes have longer horns than the Swayne's hartebeest. The horns grow in a wide "V" shape, unlike the wide bracket shape of Swayne's hartebeest and the narrow "V" of Lelwel hartebeest, curving backward and slightly inward. It occurs in Ethiopia, in a small area to the east of Omo River and north of Lake Turkana, stretching north-east of Lake Chew Bahir to near Lake Chamo. Evolution The genus Alcelaphus emerged about 4.4 million years ago in a clade whose other members were Damalops, Numidocapra, Rabaticeras, Megalotragus, Oreonagor, and Connochaetes. An analysis using phylogeographic patterns within hartebeest populations suggested a possible origin of Alcelaphus in eastern Africa. Alcelaphus quickly radiated across the African savannas, replacing several previous forms (such as a relative of the hirola). Flagstad and colleagues showed an early split in the hartebeest populations into two distinct lineages around 0.5 million years ago – one to the north and the other to the south of the equator. The northern lineage further diverged into eastern and western lineages, nearly 0.4 million years ago, most probably as a result of the expanding central African rainforest belt and subsequent contraction of savanna habitats during a period of global warming. The eastern lineage gave rise to the Coke's, Swayne's, Tora and Lelwel hartebeest; and