Mammalian vs. Reptilian Skull Morphology

Mammal and reptile are morphologically different in a few ways. Mammal skulls are synapsid: they have a single, large opening called a temporal fenestra behind each eye that allows for more attachment of jaw muscles. This muscle attachment gives mammals a larger range of motion in their jaws, which allows them to have stronger bites. Reptiles such as alligators are diapsid, which means they have two temporal fenestrae on each side of their heads, while other reptiles such as turtles do not have any of these openings and are thus referred to as anapsid. Another difference between mammal and reptile skulls is the mammalian middle ear is made up of three bones, the malleus, the incus, and the stapes, whereas the reptilian middle ear is made up of only the stapes. Reptiles have articulate and quadrate bones in their mandibles and skulls respectively, and in mammals these bones have migrated up towards the middle ear and formed the malleus and incus. Mammal skulls also differ from reptile skulls in that they have two occipital condolytes at the articulation between the skull and the cervical vertebrae. This allows mammals to move their heads up and down through, which is beneficial to them because this gives them the ability to further manipulate their food. Reptiles on the other hand only have a single occipital condolyte, which limits their head movements, most of which involve moving the entire body.