How is the gestation period for kangaroos

This depends entirely on the species of kangaroo.

There are over sixty known species of kangaroo, ranging from the largest, the Red kangaroo, to the smallest, the Musky rat kangaroo. Therefore, gestation periods vary. It should also be noted that kangaroos have the ability to suspend the development of the embryo whilst another joey is still in the pouch, so they can be in a state of continuous pregnancy.

The musky rat kangaroo has a gestation period of 19 days, whilst the red kangaroo has a gestation period of about 33 days. Most other kangaroo species have a gestation period of 31-36 days. Most of the development of the joey occurs in the pouch rather than in the womb. Young musky rat kangaroo joeys spend about 21 weeks in the pouch, while red kangaroo joeys spend an average of 9 months in the pouch.

However, in reality, pregnancy length may differ. The mother kangaroo spends most of her adult life pregnant, but in drought times, she has the ability to indefinitely "freeze" the development of the young embryo until food sources are replenished. This is called embryonic diapause.

The same situation occurs for wallabies, also members of the kangaroo family. There are many different species of wallaby but, on average, they have a gestation period of 30 days and spend 8-9 months in the pouch.