Black wildebeest the hybrid as compared to either of its parents. In some animals, the auditory bullae are highly deformed, and in others, the radius and ulna are fused. Black wildebeest are sexually dimorphic, with females being smaller in size and more slender than males. The head-and-body length is typically between . Males reach about at the shoulder, while females reach . Males typically weigh and females . A distinguishing feature in both sexes is the tail, which is long and similar to that of a horse. Its bright-white colour gives this animal the vernacular name of "white-tailed gnu", and also distinguishes
Black wildebeest to the black wildebeest, owing to their close similarity in behavior. The bulls approach each other with their heads lowered, resembling a grazing position (sometimes actually grazing). This is usually followed by movements such as standing in a reverse-parallel position, in which one male urinates and the opponent smells and performs flehmen, after which they may reverse the procedure. During this ritual or afterwards, the two can toss their horns at each other, circle one another, or even look away. Then begins the fight, which may be of low intensity (consisting of interlocking the horns and pushing each other in