They are divided into 7 groups:
* Didelphimorphia (Opossums)
* Paucituberculata (Shrew Opossums)
* Microbiotheria
* Diprotodontia (Kangaroos, Possums, Koala, Wombat)
* Notoryctemorphia (Marsupial Moles)
* Dasyuromorphia (Tasmanian devil, Quoll)
* Peramelemorphia (Bandicoot, Bilbies)
They have a pouch
Their baby lives in the pouch until they are old enough
They don't have kneecaps
They have epipubic bones
They don't have a gross communication between left and right brain hemispheres
Epipubic bones - They are pair of bones projecting forward from pelvic bones