A well-known mammal:The word kangaroo often brings to mind a picture of a big, bounding critter with long ears and a baby, or joey, peeking out of its mother's pouch. Maybe you envision Kanga and Roo from A. A. Milne's Winnie the Pooh books, or H. A. Rey's Katy No-Pocket from the story of the same name? Either way, kangaroos are perhaps Australia's best-known wildlife and are found in stories, movies, and even as sports team mascots the world over!
The kangaroo's family name, Macropodidae, means "big feet," a great description for kangaroos and their relatives. Kangaroos, wallabies, wallaroos, quokkas, pademelons, potoroos,honey possums, and tree kangaroos are all macropods. Confused about the difference between kangaroos, wallaroos, and wallabies? That's understandable! There are more than 50speciesof these marsupials, and they vary in size from critters you could hold in your hands to the giant red kangaroo that stands as tall as an adult person.
The main difference between a kangaroo and all the others is size: the six largest macropods are referred to as kangaroos. Otherwise, they are quite similar. In most species, the hind legs and feet are much larger and more powerful than the forelimbs. Their tail is long, muscular, and thick at the base, helping the kangaroo or wallaby balance and turn during hopping and providing support when it rests.
The kangaroo's muscular design lets it move in a way called saltation that is unique to macropods. This means that it hops, both feet pushing off the ground at the same time. The larger kangaroos can cover over 23feet (7 meters) per hop when cruising at top speed and have been clocked at more than 30 miles (48 kilometers) per hour in short bursts!
Like a perpetual-motion machine, hopping kangaroos are able to keep moving without expending much energy. In fact, kangaroos actually burn less energy the faster they hop, at least up to their cruising speed of 20 miles (32 kilometers) per hour. In addition to powerful leg muscles, kangaroos have a huge set of tendons in their tail that attach to the hipbones. The combination of these muscles and tendons working together helps kangaroos move efficiently. Wallabies, while smaller in stature, are built and hop in a similar manner.
When a kangaroo senses danger, it alerts its fellows by thumping its feet loudly on the ground! It can also communicate by grunting, coughing, or hissing. A mother may make a clicking or clucking sound to call her young. The kangaroo’s hands may be used to fight; this is called boxing. Dingos are a red kangaroo’s onlypredator.
The best-known macropods are the three widespread and common, large kangaroos. The largest is the red kangaroo, which is found most often on the open plains of inland Australia and can live on very little water. Maroon with a white face and belly, males are often referred to as red flyers. Male red kangaroos can be over 6 feet (1.8 meters) tall and weigh up to 200 pounds (90 kilograms)! Females, sometimes called blue flyers, are bluish gray and are smaller and faster than the males, reaching speeds of up to 30 miles (48 kilometers) per hour. Red kangaroos can, in an emergency, leap across the outback in 10-foot-high (3 meters) and 39-foot-long (12 meters) bounds. Talk about a spring in your step!
Red kangaroos prefer living in open, grassy plains, although they may also be found in scrubland and desert habitat; the slightly smaller gray kangaroos, which need more drinking water than reds, usually inhabit woodlands, though theygrazein grassy meadows at night. Those living in the eastern coastal regions have long, silver-gray hair, while those found inland have short, dark gray hair.
All three of the large kangaroos are closely related to the smaller wallabies and wallaroos that thrive in habitats ranging from wet forests to arid grasslands. There are brush, scrub, swamp, forest, and rock wallabies, which should give some clue as to the vastly different habitats these creatures call their own. Their smaller size lets them fill smaller, more varied niches than their larger cousins.
The typical kangaroo design of large, muscular hind legs and smaller forelimbs is nearly reversed in tree kangaroos, since they are climbers rather than hoppers, and they have a long, flexible tail that helps with balance. Most tree kangaroos are found in the dense rainforest canopies of New Guinea, while two are native to Australia. Like their ground-dwelling relatives, tree 'roos are herbivores and leave their trees at night to eat vegetation and grubs. The major threats toendangeredtree kangaroos are loss of habitat, being struck by cars, and being killed by dogs and/or dingoes.
