During the Permian and Triassic Eras, Much of the World's

Question

During the Permian and Triassic eras, much of the world's fauna was dominated by
A) trilobites.
B) amphibians.
C) therapsids.
D) mammals.

Accepted Answer

During the Permian and Triassic eras, therapsids (also known as mammal-like reptiles) were the dominant terrestrial vertebrates. They were the ancestors of mammals and had many mammalian characteristics such as specialized teeth and a more upright posture. Trilobites were extinct by the end of the Permian, and mammals did not evolve until the end of the Triassic. While amphibians were present during this time, they were not as dominant as therapsids.