Marsupial
Marsupials are a diverse group of mammals belonging to the infraclass Marsupialia. They are natively found in Australasia, Wallacea, and the Americas. One of the defining features of marsupials is their unique reproductive strategy, where the young are born in a relatively undeveloped state and then nurtured within a pouch on their mother's abdomen.
This article is about the mammals. For frogs, see Marsupial frog.
Living marsupials encompass a wide range of species, including kangaroos, koalas, opossums, Tasmanian devils, wombats, wallabies, and bandicoots, among others.
Marsupials constitute a clade stemming from the last common ancestor of extant metatherians, which encompasses all mammals more closely related to marsupials than to placentals. This evolutionary split between placentals and marsupials occurred at least 125 million years ago, possibly dating back over 160 million years to the Middle Jurassic-Early Cretaceous period.
Presently, close to 70% of the 334 extant species of marsupials are concentrated on the Australian continent, including mainland Australia, Tasmania, New Guinea, and nearby islands. The remaining 30% are distributed across the Americas, primarily in South America, with thirteen species in Central America and a single species, the Virginia opossum, inhabiting North America north of Mexico.
Marsupials range in size from a few grams in the long-tailed planigale,[1] to several tonnes in the extinct Diprotodon.[2]
The word marsupial comes from marsupium, the technical term for the abdominal pouch. It, in turn, is borrowed from the Latin marsupium and ultimately from the ancient Greek μάρσιππος mársippos, meaning "pouch".
Geography[edit]
In Australasia, marsupials are found in Australia, Tasmania and New Guinea; throughout the Maluku Islands, Timor and Sulawesi to the west of New Guinea, and in the Bismarck Archipelago (including the Admiralty Islands) and Solomon Islands to the east of New Guinea.
In the Americas, marsupials are found throughout South America, excluding the central/southern Andes and parts of Patagonia; and through Central America and south-central Mexico, with a single species (the Virginia opossum Didelphis virginiana) widespread in the eastern United States and along the Pacific coast.