Antelopes differ from one another almost as much as they differ from other members of the cattle, goat, and sheep family. Size is one of the most striking and variable features of antelopes: The common eland towers over most breeds of domestic cattle and can be 300 times heavier than the royal antelope.
In many species, including the eland, males are considerably larger than females. In a few species, such as the Asian black buck, males and females also differ in color.
Antelope Physical Description
Antelopes have a dense coat with short fur. Most antelopes have fawn or brown fur that helps camouflage them as they feed. But there are some exceptions to this rule. The rare zebra duiker has dark vertical stripes, while the gemsbok has gray and black fur and a vivid black-and-white face. A common feature of gazelles is a white rump, which flashes a warning signal to others when they run from danger. One gazelle, the springbok, also has a pouch of white brushlike hairs running along its back. When a springbok is alarmed, its pouch opens up, and the hairs stand on end.
All antelopes have long slender legs. Powerful muscles where the upper legs meet the antelope’s body provide leverage, increasing leg stride and speed. Although antelopes are good jumpers they are not great climbers, particularly when compared with sheep and goats. But a few do exhibit good balance—most notably the klipspringer, which stands on the tips of its hooves. Another African species, the gerenuk, is one of the few antelopes that habitually stands on its back legs. It does this to reach leaves in trees: As it stretches upward, the gerenuk uses its front legs to hold itself steady against the tree.
Antelopes are ruminants, animals that regurgitate partially digested food, called cud, and chew it again. Like other ruminants, including cattle and sheep, antelopes have well-developed cheek teeth or molars, which grind cud into a pulp. They have no upper incisors, and in order to tear off grass stems or leaves, their lower incisors press against an upper hard gum pad when they bite.
Whether they are eating or resting, antelopes rely on their keen senses to avoid danger. Their eyes face sideways, and their pupils are elongated horizontally, giving them a good view of danger from behind as well as in front. Their hearing and sense of smell are also acute—valuable features for life in the open where many predators are on the prowl after dark.
Whereas in deer only males for the most part grow antlers, in antelopes, both sexes usually have horns, although the horns of males are normally larger. In species where males have only one mate, such as the dik-dik and klipspringer, horns are little more than spikes. In species where the males compete to mate with several females, antelope horns may grow as long as 1.5 m (5 ft). Despite their large size, antelope horns are hollow and lightweight. Antelope horns are always slightly curved, and in some species, such as the black buck, they are shaped like a pair of corkscrews, spiraling in opposite directions.
Antelope life spans in the wild are difficult to determine, and most known figures relate only to captive animals. Captive gnus, for example, have lived to be over 20, while impalas have lived into their late teens. But in the wild, where predators weed out all but the fastest and fittest animals, few antelopes reach their teen years.