What is the gestation period for kangaroos (how long does it take for their young to develop from fertilization until birth)?

The gestation period for kangaroos is relatively short, lasting about 30 to 36 days. After this brief period, the underdeveloped young, called a joey, is born and immediately climbs into the mother's pouch, where it continues to develop and nurse for several months. Depending on the species, joeys may stay in the pouch for up to 8 months before venturing out.