Abstract
Among the world's most curious creatures is Australia's amazing kangaroo. He appears standing proud and tall on the Australian coat of arms, and has been a rallying symbol for national sporting teams. Benign of face, bottom-heavy of build, kangaroos outclass most of the animal kingdom in the long and high jump, boxing, and karate. Born a mere 1-1.5 centimetres (half-inch) long, and weighing less than a grain, kangaroos can grow taller than a man. As with most other marsupials, one of the three orders of mammals, they raise their young in body pouches. But kangaroos have another advantage - an expectant female can retain an embryo in ready reserve for months, until the conditions are right for its continued development.