kangaroo rat, small, jumping desert rodent, genus Dipodomys, related to the pocket mouse. There are about 20 kangaroo rat species, found throughout the arid regions of Mexico and the S and W United States. Kangaroo rats have large, mouselike heads with big eyes, external fur-lined cheek pouches for food storage, and extremely long, tufted tails. In many species the tail is longer than the combined head and body length. The total length, including the tail, is 10 to 15 in. (25-37.5 cm), depending on the species. The front limbs are very short and the back limbs extremely long and stiltlike. The animal moves by long leaps, like a kangaroo, using its tail for balance and as a rudder for turning at high speeds. Kangaroo rats have long silky fur, pale brown above and white beneath, with black and white tail tufts and black face markings. Solitary, nocturnal creatures, they live in burrows by day and forage at night for seeds, grass, and tubers. Active hoarders, they sometimes dry their food in shallow pits just below the surface of the ground, then dig it up and store it in their burrows. Like a number of other desert animals, the kangaroo rat has physiological mechanisms for conserving the water that it obtains from food or produces metabollically, so that it does not need to drink. A related genus, Microdipodops, is called the kangaroo mouse, or dwarf kangaroo rat. It is about 6 in. (15 cm) in total length and is found in the Great Basin of the W United States. Kangaroo rats are classified in the phylum Chordata, subphylum Vertebrata, class Mammalia, order Rodentia, family Heteromyidae.

kangaroo mouse: see kangaroo rat.

kangaroo, name for a variety of hopping marsupials, or pouched mammals, of the family Macropodidae, found in Australia, Tasmania, and New Guinea. The term is applied especially to the large kangaroos of the genus Macropus. Kangaroos have powerful hind legs designed for leaping, long feet, short forelimbs, and long muscular tails. The hind legs are also used to deliver blows at enemies when the animal is cornered; the feet are sharply clawed. The tail serves as a balance when the animal leaps and as a prop when it stands; the usual posture is bipedal. The handlike forepaws are used for grasping. As in most marsupials, females have a pouch surrounding the teats. The single young is born in an immature state after a gestation period of about 40 days and is suckled in the mother's pouch for about six months. After it begins to graze it returns frequently to the pouch for shelter and transport until it is too large to be carried. Kangaroos feed on grass and other vegetation; they are the chief grazers of the Australian plains. Day-active animals, they move about in herds called mobs and sleep on the ground at night. Males are called boomers, females flyers; the young are called joeys. Because many types of kangaroo have valuable hides, and because they compete with domestic livestock for grazing land, kangaroos have been extensively hunted and are now extremely reduced in numbers.

Types of Kangaroos

The largest kangaroo, and largest of all marsupials, is the great red kangaroo, M. rufus, which inhabits the inland plains of Australia. Males of this species may be over 7 ft (210 cm) tall and weigh over 200 lbs (90 kg). They are bright maroon in color, with white faces and underparts. Females, called blue flyers, are blue-gray; smaller and faster than the males, they may achieve speeds of 30 mi (48 km) per hr. The great gray kangaroo, M. canguru, is almost as large; it is found in open forest areas of E and W Australia and in Tasmania. A related kangaroo, M. robustus, is known as the wallaroo and inhabits rocky hills throughout most of the continent.

Smaller, but quite similar in appearance and behavior, are members of the kangaroo family called wallabies and pademelons, of which there are many species, classified in several genera. Some of these are plains dwellers, others live among rocks or in scrub country; most are about the size of a rabbit. Of similar size are the tree and rat kangaroos. Tree kangaroos, species of the genus Dendrolagus, are the only arboreal members of the family. Found in the rain forests of New Guinea and N Australia, they climb well and can leap from branch to branch. Rat kangaroos are omnivorous animals of ratlike appearance. They feed largely on roots and fungi; members of many species live in burrows. They are classified in several genera and are distributed throughout the Australian region.

Classification

They are classified in the phylum Chordata, subphylum Vertebrata, class Mammalia, order Marsupialia, family Macropodidae.

Kangaroo Island, small island, South Australia, S Australia, at the entrance to Gulf St. Vincent. It is 90 mi (145 km) long and 34 mi (55 km) wide. The chief products are barley, sheep, salt, gypsum, and eucalyptus oil. At its west end is Flinders Chase, a large reservation for native flora and fauna. There are many summer resorts. Kingscote (1991 pop. 1,443) is the principal settlement.

Any of about 25 species (genus Dipodomys, family Heteromyidae) of rodents that leap about on their hind legs; found in dry regions of North America. They have large heads, large eyes, short forelimbs, long hind limbs, and fur-lined external cheek pouches that open alongside the mouth. They are 4–6.5 in. (10–16 cm) long without the long tail, which usually ends in a furry tuft. They are pale buff to brown above and white below, with a white stripe on each hip. They forage by night for seeds, leaves, and other vegetation, carrying food in their cheek pouches to store in their burrows, but seldom drink water.

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Most specifically, any of six large Australasian marsupials of the family Macropodidae. The term is also used to refer to any of the family's 54 species. Most kangaroos graze on the Australian plains, but tree kangaroos are arboreal; they climb trees and leap from branch to branch. Kangaroos generally have long, powerful hind legs and feet and a long tail, thickened at the base. The hind legs enable their spectacular leaps and are also useful for self-defense; the tail is used for balance. The head is small, the ears large and rounded, and the fur soft and woolly. Females have one young (called a joey) annually; it is suckled in its mother's pouch for six months and often returns to be carried in the pouch later as well. The gray kangaroo, the best-known and second-largest species, can leap more than 30 ft (9 m). The red kangaroo is the largest species; the male may stand 6 ft (1.8 m) tall and weigh 200 lbs (90 kg). Millions are killed annually for their meat and hides and because they compete with livestock for forage. Seealso wallaby; wallaroo.

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Island, South Australia. Located at the entrance to the Gulf St. Vincent, southwest of Adelaide, Kangaroo Island is 90 mi (145 km) long with an area of 1,680 sq mi (4,350 sq km). Visited in 1802 by the English explorer Matthew Flinders, it was named for its many kangaroos. Nepean Bay was the site of the state's first temporary settlement in 1836.

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