Why does a kangroo have a pouch and a rabbit doesn't?

Answer 1

This is all to do with how the young of each animal develop.

Kangaroos are marsupials. Marsupials are mammals with pouches in which they rear their young. Marsupial young are characterised by being extremely small and undeveloped at birth. At birth, they take a long, arduous journey from the birth canal, driven purely by instinct, grabbing hold of the mother marsupial's fur which she has cleaned and made easier to traverse with saliva, to reach the pouch. Upon reaching the pouch, they latch onto a teat which swells in their mouth to prevent them from being accidentally dislodged during the mother's movements. There they stay for months, to complete their development. The joeys are unable to survive independently of their mother for much of this time.

Rabbits are not marsupials but rodents, which are placental mammals. This means the babies are born in a more advanced state, and they do not need to be attached to the mother via the teat. They can drink from the teat and then detach after the feeding.

Further, kangaroos have a single joey just once a year, whilst rabbits have numerous young several times a year. Because of this, a kangaroo joey will spend up to 9 months in its mother's pouch (depending on the species) until it is no longer dependent on its mother for protection and survival. Baby rabbits grow quickly, and there is not the same need to protect them by way of a pouch, as they grow to adulthood quickly, and there are so many in a single litter.

Answer 2

A kangaroo is a marsupial. They were made with pouches. Rabbits give birth in a nest lined with there own fur. They don't have a pouch.