The kangaroo, now the national symbol of Australia, belongs to the group of mammals called marsupials, meaning “pouched.” Female kangaroos have a pouch, like a bag with an elastic top, in which they keep their young for eight to nine months after they are born.
Marsupials are mammals; all female mammals give birth to living young. However, marsupials are unique in that their babies are born in a very undeveloped state. They finish developing outside their mother’s body, usually in her pouch.
A baby kangaroo, or joey, as it is called, grows inside its mother for only one month. When born, it is the size of a peanut. Joeys are not born in the pouch, but must crawl there. Inside this amazing pouch is everything the joey needs, milk, shelter, and even oil to keep it moist. The joey spends its first five months in the pouch full-time. At the end of this time, the joey pokes its head out, but does not venture out. Finally at eight months, the joey leaves the pouch for good, returning to its mother only to drink her milk.
The joey drops into its mother’s pouch head first, then rolls over on its back, as if it is in a hammock!