Elephant Shrews

views updated May 29 2018

Elephant Shrews

Elephant shrews or sengis are relatively small mammals in the family Macroscelididae, order Macroscelidea. Elephant shrews have a characteristic long, narrow snout that is broad at the base, and very

sensitive and flexible but not retractile. This snout is movable in circular manner at the base, and has nostrils at the end. There are four genera with some 15 species of elephant shrews, living in continental Africa and on the island of Zanzibar. Elephant shrews live in thorn bush country, grassy plains, thickets, the under-growth of forests, and on rocky outcrops.

The head and body length is 3.712.3 in (9.531.5 cm) and the tail 3.110.3 in (826.5 cm). The tail is usually slender and covered with bristles, which may be rough at the underside and terminating in knobs. There is a naked black musk gland under the tail which secretes a highly scented substance, especially in females. The body is covered with soft fur which is lacking on the rump. The two bones of the hind legs are joined. The feet have four or five toes, and the hands have five fingers. The females have two or three pairs of nipples.

The elephant shrews are active mainly in daytime, but in hot weather they may be nocturnal. These animals may hide during the day when harassed by diurnal predators, but are often seen sun bathing. They reside singly or in pairs in burrows, ground depressions, rock crevices, and in the crevices of termite mounds. Burrows of rodents are occasionally used. When running, elephant shrews leave runways with a broken appearance because of their jumping locomotion which is like a bouncing ball, running on their hind legs, with the tail extended upward.

The smaller species of elephant shrews feed on ants, termites, and slender shoots, roots, and berries, while some larger species prefer beetles. The members of the genus Elephantulus and Rhynchocyon produce squeaks, while Petrodromus make cricket-like calls. Elephantulus and Petrodromus rap their hind feet when nervous or to give an alarm. Species of Petrodromus and Rhynchocyon are known to beat their tails on the ground.

Gestation takes about two months and one or two young are born relatively large and well developed, fully covered with fur and with eyes open at birth or soon after. There is a short nursing period and elephant shrews become sexually mature at five to six weeks of age. The life span in the wild is probably 18 months or less, but captive North African elephant shrews lived 40 months. Some larger elephant shrews, such as Petrodromus tetradactylus and Rhynchocyon chrysopygus, are snared and eaten by natives.

See also Shrews.

Elephant Shrews

views updated May 14 2018

Elephant shrews

Elephant shrews are relatively small mammals in the family Macroscelididae, order Macroscelidea. Elephant shrews have a characteristic long, narrow snout that is broad at the base, and very sensitive and flexible but not retractile. This snout is movable in circular manner at the base, and has nostrils at the end. There are five genera with some 185 species of elephant shrews, living in continental Africa and on the island of Zanzibar. Elephant shrews live in thorn bush country, grassy plains, thickets, the undergrowth of forests , and on rocky outcrops.

The head and body length is 3.7–12.3 in (9.5–31.5 cm) and the tail 3.1–10.3 in (8–26.5 cm). The tail is usually slender and covered with bristles, which may be rough at the underside and terminating in knobs. There is a naked black musk gland under the tail which secretes a highly scented substance, especially in females. The body is covered with soft fur which is lacking on the rump. The two bones of the hind legs are joined. The feet have four or five toes, and the hands have five fingers. The females have two or three pairs of mammae.

The elephant shrews are active mainly in daytime, but in hot weather they may be nocturnal. These animals may hide during the day when harassed by diurnal predators, but are often seen sun bathing. They reside singly or in pairs in burrows, ground depressions, rock crevices, and in the crevices of termite mounds. Burrows of rodents are occasionally used. When running, elephant shrews leave runways with a broken appearance because of their jumping locomotion which is like a bouncing ball, running on their hind legs, with the tail extended upward.

The smaller species of elephant shrews feed on ants , termites , and slender shoots, roots, and berries, while some larger species prefer beetles . The members of the genus Elephantulus and Rhynchocyon produce squeaks, while Petrodromus make cricket-like calls. Elephantulus and Petrodromus rap their hind feet when nervous or to give an alarm. Species of Petrodromus and Rhynchocyon are known to beat their tails on the ground.

Gestation takes about two months and one or two young are born relatively large and well developed, fully covered with fur and with eyes open at birth or soon after. There is a short nursing period and elephant shrews become sexually mature at five to six weeks of age. The life span in the wild is probably 18 months or less, but captive North African elephant shrews lived 40 months. Larger elephant shrews of the genus Petrodromus of East Africa are snared and eaten by natives.

See also Shrews.

Macroscelidea

views updated Jun 08 2018

Macroscelidea (Macroscelididae; elephant shrews; cohort Unguiculata, order Insectivora) A suborder of omnivorous mammals (now generally classed as a separate order) in which the hind limbs are elongated, enabling the animals to jump well, and the snout is elongated. The molars are large and squared, like those of ungulates. Macroscelids are known from the early Oligocene and are believed to be an evolutionary offshoot from a primitive insectivore stock, confined to Africa and with no close living relatives. There are many species, found in N. Africa and south of the Sahara.