Marsupials are mammals that typically give birth to underdeveloped young that continue growing while nursing, often in a pouch. There are more than 250 living species.
Well-known examples include kangaroos, wallabies, wombats, the koala, the Tasmanian devil, and opossums. Most species live in Australia, New Guinea, and nearby islands; about 70 live in the Americas, including the Virginia opossum in North America.