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Hyraxes

rock africa tree habitat

Hyraxes are rabbit-sized, hoofed African mammals that surprisingly share a common ancestry with elephants and manatees, or seacows. Hyraxes were originally thought to be rodents, and were later grouped with rhinoceroses. They are now placed in an order of their own, the Hyracoidea, since they share many common features of primitive ungulates. The fossil record indicates that hyraxes were the most prevalent medium-sized browsing and grazing animal 40 million years ago, ranging in size from that of contemporary hyraxes to that of a tapir. As competition with the bovid family (African and Asian antelope, bison, sheep, goats, and cattle) increased, hyraxes retreated to the more peripheral habitats with rocks and more trees. Rock hyraxes (Procavia capeasis) are dependent upon suitable habitat in rocky outcrops (kopjes) and cliffs, but nevertheless the five species of rock hyraxes have the widest geographical and altitudinal distribution in Africa. Tree hyraxes, (Dendrohyrax arboreus) prefer arboreal habitats and are found in Zaire, East Africa, and South Africa. Another species of hyrax (D. dorsalis) is found in West Africa.

Small and compact with short rounded ears, rock hyraxes have only a tiny stump of a tail. Their coat is coarse and thick, ranging in color from light gray to black. Males and females are approximately the same size and show little sexual dimorphism. The feet of hyraxes have naked rubbery pads with numerous sweat glands. There are four toes on the forefoot and three on the hind foot. All the digits have flattened nails, except the inner toe of the hind foot which has a sharp-edged nail that is used for grooming. Hyraxes have grinding teeth, like those found in rhinoceroses and a pair of incisors that are sharp and dagger-like.

The social organization of rock hyraxes consists of stable family groups composed of one adult territorial male and three to seven related adult females, commonly known as a harem. Females breed once per year producing litters of one to four young after a gestation period of seven-and-one-half to eight months. Hyraxes can live ten years or longer. They are gregarious animals, and may often be seen sunbathing on rocks or in cooler periods, huddling close together. Hyraxes regulate their body temperature poorly and have a low metabolic rate for a mammal.

Rock hyraxes feed mostly on grasses, and supplement their diet with herbage, leaves, berries, fruit, and the bark of trees during the dry season. Hyraxes have a tolerance for eating highly poisonous plants. They also need little water to survive, by virtue of efficient kidneys obtaining moisture from their food. In spite of their compact build, hyraxes are agile in their movements and relatively good jumpers. Both hearing and sight are excellent. Their main predator is the Verreaux eagle. Other enemies are martial and tawny eagles, leopards, lions, servals, caracals, jackals, large civets, spotted hyenas, and several snake species. To guard against predators, an alarm whistle is sounded. Hyraxes may also growl with gnashing teeth and give long-drawn piercing screams.

Rock hyraxes habitually defecate in the same spot, creating a pile of dried, hardened excrement which contains hyraceum, a substance used to make perfumes. Although tree hyraxes are heavily hunted and suffer from habitat destruction, rock hyraxes appear to be stable in their population numbers with little threat to their habitat. Rock hyraxes are also known as rock-rabbits, coneys, dassies, and kupdas, while tree hyraxes are also known as tree bears. The Syrian hyrax (Procavia syriaca) is similar to the rock hyrax and is the "coney" referred to in the Bible.

Betsy A. Leonard

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