How do kangaroos get pouches?

Female kangaroos are born with a pouch called a marsupium. It is a specialised skin fold located on the ventral side of the abdomen. Just like human babies develop within the uterus, kangaroo joeys are born in a relatively underdeveloped state after a short gestation period. They then crawl into their mother's pouch, where they continue to develop and receive nourishment.

The pouch is not a permanent feature in male kangaroos. It starts developing in female joeys even before they are born and is fully formed by the time they reach sexual maturity. The pouch plays a vital role in nurturing and protecting the young joey during its early and vulnerable stages of development.