Question Detail
Question
Mammals appeared in the Era: A. Paleozoic B. Mesozoic C. Cenozoic D. Mnemonic E. Triassic
Correct Answer
Option B is the correct answer.
Detailed Explanation
The first mammals evolved from synapsid reptiles during the Mesozoic Era, specifically in the Triassic Period. They lived alongside the dinosaurs but were small and nocturnal. They only became dominant in the following Cenozoic Era.
Hint
They first appeared when dinosaurs were around, but they were small and in their shadow.