Identifying a Metatherial Skull (2)-Polyprotodonts

Once identified as polyprotodont there are several ways determine what order and, subsequently, what family a skull belongs to. One way is to look at dental formula: of the polyprotodont orders we are looking at in lab, two have 4 upper incisors and 3 lower incisors on each side of their skulls(4/3), and one has 5 upper incisors and 4 lower incisors on each side of its skull (5/4) . The order that has 5/4 incisors is O. Didelphimorphia, which includes only one family, F. Didelphidae. Distinguishing between the remaining two orders can be done by looking at the canines: O. Dasyuromorphia has large canines, whereas O. Peramelemorphia has very small canines. They can also be differentiated by their sizes, as O. Dasyuromorphia is much larger than O. Peramelemorphia. Based on the families we studied in lab, if the skull belongs to O. Dasyuromorphia then it is in F. Dasyuridae, and if the skull belongs in O. Peramelemorphia then it is in F. Peramelidae.