s can stand erect on their hind legs to browse on high foliage
Body and covering Antelope vary greatly in size. For example, a male
common eland can measure at the shoulder and weigh almost , whereas an adult
royal antelope may stand only at the shoulder and weigh a mere . Antelope have a wide variety of coverings, though most have a dense coat of short fur. In most species, the coat (pelage) is some variation of a brown colour (or several shades of brown), often with white or pale underbodies. Exceptions include the zebra-marked
zebra duiker, the grey, black, and white
Jentink's duiker, and the
black lechwe. Most of the "spiral-horned" antelope have pale, vertical stripes on their backs. Many desert and semidesert species are particularly pale, some almost silvery or whitish (e.g. Arabian oryx); the
beisa and
southern oryxes have gray and black pelages with vivid black-and-white faces. Common features of various
gazelles are white rumps, which flash a warning to others when they run from danger, and dark stripes midbody (the latter feature is also shared by the springbok and beira). The springbok also has a pouch of white, brushlike hairs running along its back, which opens up when the animal senses danger, causing the dorsal hairs to stand on end. Many antelope are sexually dimorphic. In most species, both sexes have horns, but those of males tend to be larger. Males tend to be larger than the females, but exceptions in which the females tend to be heavier than the males include the
bush duiker,
dwarf antelope,
Cape grysbok, and
oribi, all rather small species. A number of species have hornless females (e.g.,
sitatunga,
red lechwe, and
suni). In some species, the males and females have differently coloured pelages (e.g.
blackbuck and
nyala). Many wild antelopes are characterized by high running and jumping abilities. Their main defence against predators is to try to escape. Species such as
black wildebeest,
springbok,
blesbok,
mountain reedbuck,
greater kudu as well the
European fallow deer have high concentrations of
glycolitic fast twitch type IIx muscle fibers; smaller species naturally have higher concentrations of type IIx fibers than larger species. Although their concentration of type IIx fibers is still lower than that of the wild
cheetah, other running-adapted mammal; wild cheetah
vastus lateralis muscle have a concentration of 76% of type IIx fibers, compared to 58% of springbok, 57% of mountain reedbuck, 55% of blesbok, 48% of European fallow deer, 43% of greater kudu and 30% black wildebeest. The activity of the anaerobic enzyme
LDH, an indicator of a principally anaerobic muscle metabolism, is around 4 times more higher than that of humans, a level of activity comparable to that of the
lion, but lower than that of the wild
caracal and especially that of the wild cheetah; LDH activity is 6 times higher than that of the humans in caracal and 9 times higher in the wild cheetah. Both impala and
reindeer have a CS level activity comparable to that of the human endurance runners and their muscle metabolism appears to be principally aerobic, indicating muscles capable of high endurance. Compared to the reindeer in which hind and forelimb muscles form 14.8% and 10.9% of their body mass, respectively. Antelopes tend to have very long limbs for their body masses; a 60 kg
Peter's gazelle have a shoulder height of 90 cm, whereas a cheetah and a
leopard of the same body mass have a shoulder height of 79 cm and 64 cm, respectively.
Pronghorns and Old World antelopes have greater elongation and weight reduction in the distal parts of their limbs (Forearms, shins, front and hind feet), than the cheetah, the fastest land animal, indicating that longer limbs with more elongated and lighter distal parts are not as necessary for reaching the highest speeds for short periods of time, but are more necessary for maintaining higher speeds for longer periods of time. A maximum running speed of 63.7 km/h for the impala and 54 km/h for the
blue wildebeest has been estimated by GPS-
IMU collars. A top speed of 65.2 km/h is obtained by calculating the distance and time it takes a
Thomson's gazelle to escape from an approaching human. Film analysis of lion hunts gives maximum speeds of 90–97 km/h for the Thomson's gazelle. By speedometer reading when an animal runs alongside a car on a straight course, a maximum speed of up to 70 km/h has been estimated for the
eland and the
topi, and up to 80 km/h for the
hartebeest, blue wildebeest,
Grant's gazelle and Thomson's gazelle. The
saiga antelope has been clocked at 80 km/h when running alongside a motorcycle. Pronghorns are capable of running as fast as Old World antelopes, The speeds of the pronghorn were determined by reading the speedometer when the animals ran parallel to a moving vehicle. Impalas can jump highs of 2.4 m (8 ft).
Common elands can jump cleanly over 2.7 m fences. Female Thomson's gazelles have been reported to be faster and more agile than males. Meanwhile, the concentration of muscle glycogen in cheetahs is very similar between males and females.
Sensory and digestive systems Antelope are
ruminants, so they have well-developed
molar teeth, which grind
cud (food balls stored in the stomach) into a pulp for further digestion. They have no upper incisors, but rather a hard upper gum pad, against which their lower incisors bite to tear grass stems and leaves. Like many other
herbivores, antelope rely on keen senses to avoid predators. Their eyes are placed on the sides of their heads, giving them a broad radius of vision with minimal binocular vision. Their horizontally elongated pupils also help in this respect. Acute senses of smell and hearing give antelope the ability to perceive danger at night out in the open (when predators are often on the prowl). These same senses play an important role in contact between individuals of the same species; markings on their heads, ears, legs, and rumps are used in such communication. Many species "flash" such markings, as well as their tails; vocal communications include loud barks, whistles, "moos", and trumpeting; many species also use
scent marking to define their
territories or simply to maintain contact with their relatives and neighbors.
Antelope horns The size and shape of antelope horns varies greatly. Those of the duikers and dwarf antelope tend to be simple "spikes", but differ in the angle to the head from backward curved and backward pointing (e.g.
yellow-backed duiker) to straight and upright (e.g.
steenbok). Other groups have twisted (e.g.
common eland), spiral (e.g.
greater kudu), "recurved" (e.g. the
reedbucks), lyrate (e.g.
impala), or long, curved (e.g. the
oryxes) horns. Horns are not shed and their bony cores are covered with a thick, persistent sheath of
horny material, both of which distinguish them from antlers. Antelope horns are effective stabbing weapons against predators (Although there is a risk that the long horns getting stuck in the predator's body), and tend to be better developed in those species where males fight over females (large herd antelope) than in solitary or
lekking species. With male-male competition for mates, horns are clashed in combat. Males more commonly use their horns against each other than against another species. The boss of the horns is typically arranged in such a way that two antelope striking at each other's horns cannot crack each other's skulls, making a fight via horn more ritualized than dangerous. Many species have ridges in their horns for at least two-thirds the length of their horns, but these ridges are not a direct indicator of age. ==Behavior==