As terrestrial organisms,both insects and vertebrates evolved legs with joints,but the last common ancestor shared by these lineages existed long before vertebrates had evolved.This knowledge makes it possible to predict that
A) other aspects of leg anatomy, such as fingernails and the number of digits, will also be shared among the two lineages.
B) the DNA sequences that direct leg formation in insects and vertebrates will be very different.
C) future evolutionary developments in these lineages will also parallel one another.
D) the embryos of insects and vertebrates will share many additional developmental characteristics.

Question

Quizplus · Accepted Answer

The statement implies that while the last common ancestor had evolved legs with joints, it existed before vertebrates had evolved. Therefore, the DNA sequences that direct leg formation in insects and vertebrates would be very different, and the two lineages may have evolved additional leg anatomy separately. Choices A, C, and D are unrelated to the information provided in the statement.

As Terrestrial Organisms,both Insects and Vertebrates Evolved Legs with Joints,but