The kangaroo is a marsupial from the family Macropodidae. In common use the term is used to describe the largest species from this family, especially those of the genus Macropus, red kangaroo, antilopine kangaroo, eastern grey kangaroo and western grey kangaroo. Kangaroos are endemic to Australia.Kangaroos have large, powerful hind legs, large feet adapted for leaping, a long muscular tail for balance, and a small head. Like most marsupials, female kangaroos have a pouch called a marsupium in which joeys complete postnatal development.Larger kangaroos have adapted much better than smaller Macropods to land clearing for pastoral agriculture and habitat changes brought to the Australian landscape by humans. Many of the smaller Macropods are rare and endangered species, whilst the larger species of Kangaroos prosper to become relatively plentiful.The kangaroo is an unofficial symbol of Australia and appears as an emblem on the Australian coat of arms and on some of its currency and is used by some of Australia's well known organisations, including Qantas and the Royal Australian Air Force. The kangaroo is important to both Australian culture and the national image, and consequently there are numerous popular culture references.