Antelope are graceful animals that can run at speeds exceeding forty miles an hour and can sustain that pace longer than most of the predators pursuing them.With over seventy species of antelope observed and identified, there is a considerable range of characteristics among them. They range in size fromthe diminutive royal antelope (Neotragus pygmaeus) that stands about ten inches high and can weigh as little as four pounds, to the eland (Tauratragus derbianus) that, when fully grown, can stand six feet at the shoulders and weigh almost a ton.
Although most antelope live in grasslands, savannas, and forests, the tiny dik-dik (Madoqua) lives in semiarid regions. Whereas most antelope are gregarious animals that travel in herds for mutual protection, the bushback (Tragelaphus scriptus) is an elusive animal that travels alone and is active mostly at night. It avoids other antelope except for mating. The bongo (Boocercus eurycerus) travels in small groups, but often, particularly in old age, is solitary.
The names of various species of antelope reflect the colonial history of the parts of Africa in which they are prevalent. Settlers from the Netherlands named the dik-dik, the wildebeest (Connochaetes), the blesbok, and the duiker (Sylvicapra grimmia). The oryx and gazelle were named by French settlers. Impala (Aepyseros melampus) and kongoni are names drawn fromthe native Swahili language.
Physical Features of Antelope
Antelope of all species are generally slim, with long legs that can carry them at considerable speed when speed is necessary for survival. Antelope appear in a variety of colors-white, black, brown, gray, golden, orange, reddish, or a mixture of these colors. The red-orange bongo is particularly striking, sporting twelve thin white stripes down its side. Baby antelope frequently have white spots and stripes that disappear in adulthood.
Although they vary greatly in size, nearly all antelope, like all bovines and regardless of size, have two horns that are hollow inside and covered with a sheath, and that vary significantly from species to species. In the males of one species, the four-horned antelope (Tetracerus quadricornis), there are two sets of horns. One set, on the top of the head, is about five inches long, while a second set, on the forehead, is about two inches long.
Some antelope horns are quite long. The horns of the kudu (Tragelaphus strepsiceros) are shaped like corkscrews and can grow to five feet. In most species, both males and females have horns that, unlike the deer's, are not shed throughout the course of their lives. Usually the horns growout of the top of the head and sweep backward. In the addax (Addax nasomaculatus), the horns have a spiral shape, while in the gemsbok (Oryx gazella), the horns are straight and swordlike.
Regardless of shape, horns are important to antelope. When they engage in mating competition, they use their horns extensively. Their chief defense mechanisms, however, are the protection gained from traveling in large herds and their ability to outrun most of their predators.
Because their diet consists of plants, which take longer to digest than meats, antelope have larger stomachs and longer intestines than carnivores. Like other bovines, an antelope has a rumen, a first stomach where food is stored when it is eaten and from which it is regurgitated for the animal to chew as cud.
Having lost their "thumbs" and "big toes" as they evolved, antelope developed split hooves from what are essentially overgrown toenails. They stand and run on the center hooves. They have a remarkable agility in running because they have a unique bone, the astragalus, located between the leg and the foot. It is pulleyshaped at both ends, giving antelope their speed and agility.
The History of Antelope
Some fossil remains of antelope date back to the end of the Cretaceous period, sixty-five million years ago. At that time some catastrophic event, not yet clearly identified, wiped out most complex life on earth, although the smaller species of antelope perhaps survived in limited numbers.
Early Bovidae were found in Eurasia and Africa, where antelope still live, although as northern Eurasia became cooler, antelope migrated gradually to more temperate climates, where the grasses and other plants they depended upon for food grew year around.
The American pronghorn (Antilocapra americana) roved the plains and grasslands as far north as Alberta, Canada, and as far south as northern Mexico, although its current range ismuchsmaller. Fossil evidence suggests that the pronghorn lived alone or in small herds during the summer but that it became part of a large herd in winter, presumably to keep warm.
Migration and Eating Habits
All antelope are herbivores (vegetarians). They usually travel slowly within the security of their herds. Because of their numbers, they can anticipate danger as they travel and avoid it when it is imminent.
As they move through their habitats, some species, such as the wildebeest (also called the gnu), graze on the grass of the savannas in which they usually live. Species whose habitat is in forests tend to eat the leaves and slender branches of trees, often standing on their hind legs to reach these delicacies. Such antelope are called browsers.
Migrations are necessary for most antelope, as they exhaust the food supply in one area and are forced to move on to another. During dry periods, antelope usually move to wetter areas, where grass is more plentiful than in the arid regions. Such migrations are becoming increasingly difficult for these animals because of Africa's growing population. The development of large areas of land to accommodate the increasing human population is blocking the paths antelope once followed in their quest for food.
Having no permanent shelters, antelope follow cyclical routes that may cover more than two hundred square miles in any year. Their herds usually contain several hundred animals. Some antelope may be members of one herd in summer and of another herd in winter. Some, especially the old, the unattached, and the pregnant, may take time out from their herds for temporary solitude in marshes, along riverbanks, or in thick forests. Pregnant antelopewhodo this usually return to their herds as soon as their young are strong enough to follow them.
In order to assure the future of the antelope, reserves have been set up in some African countries. In these reserves, animals are protected from hunters and poachers. Attempts are made to guarantee that their food supply will not be compromised.
Mating and Reproduction
Within most antelope species there is no specific breeding season. Four to ten months following mating, the female antelope usually produces a single offspring, referred to in the larger species as a calf and in the smaller species as a fawn. Although single births are most common, the duiker frequently produces twins.
Once born, the offspring is usually hidden in grass or underbrush until it is strong enough to join the herd. This protective period lasts from four to eight weeks in most species, although among the reedbucks it lasts for four months. The young of some species, such as the wildebeest, are able to run within eight minutes of being born. Because of their vulnerability to predators, after the period of hiding young antelope are usually kept within the inner areas of the herd where their mothers can monitor them. Although infant mortality is high among antelope through both predation and disease, those that survive to adulthood can expect to live for up to twenty years. Human predators have been more threatening to antelope than such predators as tigers, lions, and cheetahs. As a result, some species, such as the bonetok (Damaliscus pygarus), currently exist only within the protection of animal reserves.
Farmers have indiscriminately shot many antelope because these animals eat the wild grasses that the farmers need to feed their livestock. As civilization has encroached upon areas once the sole domain of wild animals, domesticated animals have brought new diseases into those areas. Many antelope, especially calves and fawns, have succumbed to such diseases.
The Speed of Antelope
Although it is reasonably intelligent and has strong senses of sight and smell, the antelope's best defensive weapons are speed and agility. The impala has been known to jump nearly eight feet high and to bound as much as thirty-three feet in a single leap. The duiker, although it lacks the strength to jump as high and as far as the impala, can move very rapidly and, when it is being pursued, does so in a zig-zag pattern. It will finally elude its pursuers by diving into dense underbrush for protection.
What gives antelope their great propulsion in running is that they raise their two front legs, one after the other, and then their two hind legs. This gives them a forward thrust virtually unequaled in the animal world.
Tribes: Reduncini (reedbucks, waterbucks, rheboks), Alecphalini (gnus, hertebeets, impalas), Hippotragini (horselike antelope) Genus and species: Eleven genera and twenty-four species
Geographical location: Africa, North America, and parts of Asia
Habitat: Grasslands, savannas, and forests Gestational period: Four to ten months, depending on the species
Life span: Between fifteen and twenty years Special anatomy: Hooves, horns, slim legs
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