Bulls grow darker with age and become black about the head and neck. Both male and female have massive horns that spiral in one complete twist, but the female's are not as large as the male's. The Gemsbok , Oryx gazella , may not be the fleetest antelope on the African plains, but it requires an exceptionally fast horse to overtake one. When hard pressed or attacked, the gemsbok will boldly defend itself. Both sexes have horns but the females are longer.
Gemsboks are sociable animals, spending time on open plains.
They walk along in single file. Their general color is grayish brown with a black stripe extending along the lower sides of the body. The gemsbok is one kind of a group of antelopes known as oryxes. Other oryxes are much like their big relative the gemsbok. The White Oryx inhabits the deserts of North Africa.