Which of the following represents the strongest evidence that two of the three middle ear bones of mammals are homologous to certain reptilian jawbones?
A) They are similar in size to the reptilian jawbones.
B) They are similar in shape to the reptilian jawbones.
C) The mammalian jaw has fewer bones than does the reptilian jaw.
D) These bones can be observed to move from the developing jaw to the developing middle ear in mammalian embryos.
E) Mammals can hear better than reptiles.

Question

Quizplus · Accepted Answer

The observation of the movement of these bones from the developing jaw to developing middle ear in mammalian embryos provides the strongest evidence of homology between these bones and certain reptilian jawbones. This process is known as the embryonic transformation. The similarity in size or shape alone may not be enough to indicate homology. The variation in jawbone numbers between the two groups is not relevant to the homology of specific bones. The ability to hear better in mammals than reptiles is not directly related to the homology of these bones.

Which of the Following Represents the Strongest Evidence That Two