Usuario:RichardWeiss/cromanexo1
De Wikipedia, la enciclopedia encyclopedia
The class Mammalia (mammals) is divided into two subclasses based on reproductive techniques: egg-laying mammals (monotremes) and mammals which give live birth (therians). The latter subclass is divided into two infraclasses: pouched mammals (marsupials) and placental mammals (eutherians).
This list contains the monotremes and marsupials. For placental mammals, see List of placental mammals.