The class Mammalia pertains to any of the endothermic vertebrates identifiable by the following characteristics: a neocortex, three middle ear bones, a lower jaw made of a single bone, a hairy body covering, a thoracic diaphragm, a four-chambered heart, and females that are mostly viviparous. This taxonomic class can be subdivided into three: (1) Placentalia (placentals), (2) Monotremata (monotremes), and (3) Marsupialia (marsupials).
Marsupialia is an infraclass of Mammalia, including nearly all the mammals of Australia and the adjacent islands, together with the opossums of America. They differ from ordinary mammals in having the corpus callosum very small, in being implacental, and in having their young born while very immature. The female generally carries the young for some time after birth in an external pouch, or marsupium.
Word origin: Latin marsupium, marsuppium (“pouch, purse”)
- Kingdom: Animalia
- Phylum: Chordata
- Clade: Synapsida
- Class: Mammalia
- Clade: Metatheria
- Infraclass: Marsupialia [Illiger, 1811]
Other common name(s):