For purposes of differentiation, what is the unique feature of the jaw fossils of nonmammalian tetrapods?
A) Lower jaw and upper jaws hinge between the same bones.
B) Lower jaw is composed of several bones.
C) There are three bones in the middle ear.
D) Teeth are differentiated for function.

Question

Quizplus · Accepted Answer

Unlike the lower jaw of mammals, the lower jaw of nonmammalian tetrapods is composed of several bones, including the dentary, angular, and articular bones. This unique feature can be used to differentiate between mammalian and nonmammalian fossils.

For Purposes of Differentiation, What Is the Unique Feature of the Jaw