Kangaroos are giant marsupials endemic to Australia. They are identified by their strong back legs, large feet, muscular tails, short fur, and long, pointed ears. Female kangaroos have pouches that carry mammary glands, where their babies live until they are old enough to surface.
The pouch is a characteristic feature of female Kangaroos. Research has confirmed that Kangaroos give birth to a live, but comparatively underdeveloped fetus called a joey. When the joey is born, it inches from inside the mother to the pouch. The pouch is a wrinkle of skin with a unique opening that covers the teats. Inside the pouch, the blind baby fastens to one of the mother’s breasts and stays connected for as long as it takes to grow and develop to an early stage.
Evolution of Kangaroos
Around 3 million years ago, in an Australian forest, a small possum-like animal scaled down from the woods and emerged into a fantastic array of creatures.
One of these was a monstrous, leaf-munching kangaroo, that weighed hundreds of pounds, probably walked like a dinosaur, and vanished about 15,000 years ago. This gave us the present-day kangaroo jumping and relaxing down-under.
Locomotion in Kangaroos
Kangaroos are the only big mammals to use hopping as a method of locomotion. The convenient hopping speed for a red kangaroo is approximately 12–16 mph, but speeds of up to 43 mph can be achieved over short distances, while it can maintain 25 mph for almost 1.2 miles. During a hop, the robust gastrocnemius muscles lift the body off the ground while the smaller tissue connects near the large fourth toe and is utilized for push-off.
Kangaroos have single-chambered stomachs, unlike those of sheep and cows, which have four sections. They sometimes vomit the vegetation they have eaten, chew it as cud, and then swallow it again for ultimate digestion. However, this is a different, more vigorous activity than it is in ruminants, and does not occur as frequently.
Kangaroos rarely have any major natural predators. However, wedge-tailed eagles and other raptors usually eat kangaroo corpse. Goannas and other carnivorous reptiles also pose a danger to smaller kangaroo species when other food sources lack.
Social and sexual behavior
Groups of kangaroos are called troupes, which usually have ten or more kangaroos in them. Living in troupes can protect some of the weaker members of the group.
The sexual exercise of kangaroos consists of consort pairs. Oestrous females wander widely and draw the attention of males with prominent signals. A male will observe a female and follow her every move. He sniffs her urine to see if she is in oestrus, a method displaying the flehmen response. The male will then move to corner her slowly to avoid alarming her. If the female does not flee away, the male will proceed by licking, scratching, and pawing her, and mating will follow.