What do you think accounts for these differences? How might some of these differences be possible
adaptations?

I think that the differences between the skull shape and brow size have to deal extra protection needed , especially due to the eye shape. The shorter teeth were for the more evolved species which used tools and were herbivores or omnivores that did not need sharp teeth to tear flesh as the other which primarily hunted themselves and ate mostly meat.

Explanation:

there really is life in the deepest part

answer:

sequence 1- deletion

                  2- duplication

                  3- insertion

                  4- substitute

                  5- inversion