Australia and South America were isolated from other continents during much of the Tertiary, and marsupial mammals thrived and diversified there, while placental mammals took over similar roles on ...

Marsupials used to be considered an evolutionary stepping stone between egg-laying mammals called monotremes, such as platypuses, and placental mammals, such as humans, according to the new study.

Trekking into the outback west of Sydney, Australia, Darwin is struck by how different the marsupials here are to the placental mammals of Europe. He gets a close look at the anatomy of a rat ...

Marsupials have split from placental mammals about 120–180 million years ago. If marsupials had functional brown fat and its thermogenic protein, it would suggest that the organ existed before ...

By contrast, strepsirrhine primates tend to have brain sizes that are essentially "average" for placental mammals of comparable body mass. Strepsirrhines as a group thus exhibit a range of ...