How It Works

Joey to Adult: The Complete Kangaroo Life Cycle

by · 13/03/2026

These big-footed marsupials have evolved an amazing lifecycle that is fully geared for the species’ survival
A close-up shot of a young joey kangaroo peeking out from its mother's pouch. The joey has soft, brown fur, large dark eyes, and alert ears, with one small paw visible resting against the mother’s light tan fur.
Image credit: Getty Images/Westend61

A national symbol of the land down under, kangaroos not only look incredible bounding their way over the sun-scorched Australian outback, but they also have one of the most interesting and extraordinary lifecycles in the entire animal kingdom.

Mating happens all year round, and mother kangaroos are pregnant for around one month. When the baby (joey) kangaroo is born it is the size of a jellybean – the new-born is blind, hairless and so small that its mother can’t even touch it yet.

She licks a pathway through her fur and the joey uses this (guided by its sense of smell), along with its sharp claws, to make its way up her body.

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It reaches the safety of the pouch – virtually unaided – where it will continue its development. Within the pouch are the mother’s teats. These provide the young ‘roo with a rich milk full of essential nutrients. The joey spends about eight more months growing in its mother’s pouch before taking its first tentative hops outside.

Joeys will suckle on their mother’s milk until they are around 12–18 months old when they will begin to adopt the usual kangaroo diet of grasses, leaves and ferns.

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The pouch is still very much a safe haven from the outside world, and joeys will still be carried in this comfortable papoose until they are kicked out to make room for younger brothers and sisters.

From pouch to outback

The strange and fascinating development of a kangaroo

Image credit: ©Future/Geoff Shaw

  1. Boxing match: Male kangaroos will box for dominance. They live in highly social groups known as mobs.

  2. Mating season: The dominant male has exclusive breeding rights. Mating happens all year round but is often concentrated in spring, when food is plentiful.

  3. Development: Joeys are in the womb for around 33 days, but mother kangaroos can delay birth until conditions are right.

  4. Birth: After around 33 days the tiny joey is born and crawls through its mother’s fur into the safety of her pouch.

  5. Pouch development: Once inside the pouch, the immature ‘roo’ instinctively attaches itself to a teat to feed off its mother’s milk.

  6. Two uteri: The female kangaroo’s reproductive system is structured so that it can raise three joeys at a time – one in the womb, one in and one out of the pouch!

  7. Hopping: When joeys become stronger they explore the outside world, but they always dive back into the pouch for protection.

  8. Feeding: Joeys rely on milk for over a year. Mother kangaroos can produce different types of milk for different growth stages.

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