Physical characteristics

Sengis can charm the viewer with their rather humorous and endearing appearance and behavior. The sight of a sengi calls to mind a mouse with long, spindly legs and a mobile, slightly downturned snout varying in length among species. The long legs enable a sengi to walk, trot, run, or hop like a large, long-legged mammal, rather than with the scampering motions common among other small mammals. The body is compact, the head large in proportion. The coat is soft and full. The eyes are large, dark, and limpid, and the long proboscis moves continually in hesitant, circular twitchings. The effect is cute and slightly cartoonish.

The different sengi species share similar body proportions, ranging from mouse-sized to rabbit-sized. The Rhynchocyon species are the largest, with an adult head and body length of 9-12.5 in (235-315 mm), the tail adding another 7.5-10 in (190-263 mm). Adult weights can reach 14.5-15.5 oz (408-550 g). An example of a smaller sengi species is the four-toed sengi (Petrodromus tetradactylus), with an adult head and body length of 7-8.5 in (185-220 mm), tail length of 5-7 in (130-180 mm), and weight of 5-9 oz (150-280 g), but still large in comparison to the round-eared sengi (Macroscelides proboscideus) and other Elephantulus species, that are smaller and more mouselike in appearance, with adult head-and-body lengths of 3.5-6 in (90-145 mm), tail lengths of 3-6.5 in (80-165 mm), and weights of 1-2.5 oz (25-70 g).

Larger sengi species tend toward bright colors and patterns, while smaller species display more camouflaging browns and grays, often closely matching the soil color of a particular area. There is little sexual dimorphism throughout the family.

Sengi limbs feature long bones, the hindlimbs longer than the forelimbs, for cursorial (running) and ricochetal (hopping weith the hind legs) locomotion. The tibia and fibula (lower bones of the hindlimbs) are long and fused, the metatarsals are lengthened, and the ulna and radius (lower bones of the forelimbs) are also long, thus lengthening the stride and contributing to high-speed running and jumping.

Numbers and arrangements of digits vary throughout the family, from the traditional 10 fingers-10 toes arrangement to various reductions and modifications, described below in the species accounts.

The long tail is furless or sprouts bristles that vary in density and texture among species.

A sengi's mobile, somewhat flexible snout, which inspired the "elephant" word in the old common name, is both sense organ and tool. When not foraging, a sengi continually moves its snout in a subdued, circular motion from the base, seeking scents. When foraging, a sengi pokes its snout into

An eastern rock sengi (Elephantulus myurus) checking for predators. (Photo by Animals Animals ©Ingrid Van Den Berg. Reproduced by permission.)
A checkered sengi (Rhynchocyon cirnei) in its den in Democratic Republic of the Congo (Zaire). Photo by Animals Animals ©Bruce Davidson. Reproduced by permission.)

crevices or leaf litter, sniffing for food. The nostrils are located at the forward end of the snout. Long sensory vibris-sae, or whiskers, arise from the base of the snout.

The senses of smell, vision and hearing are well-developed and highly tuned. The eyes are conspicuously large, dark, and limpid. Most species have a pale ring around each eye. The ears are large in proportion to the head, and in the Elephan-tulus species, the auditory bulla is almost grotesquely enlarged, to enhance the animal's already acute hearing abilities. The braincase is relatively large, and more complex than that of similarly-sized insectivores.

Sengi bodies are riddled with scent glands, at the base of the tail, soles of the feet, chest, behind the ears, at the corners of the mouth and in the genital and anal regions, with which they mark territory.

Metabolic rates among sengi species are like those in similarly small mammals, not lower or fluctuating, as in shrews. A few sengi species, such as the North African sengi (Ele-phantulus rozeti), can adjust metabolism and activity to changes in their environments, going into torpor when temperatures or food availability go low.

A sengi lives from one to five years in the wild. The record longevity, held by a captive Bushveld sengi (E. intufi), is eight years and nine months.

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