The first mammals appeared over _______________ years ago and the earliest primates appeared about _______________ years ago.

Question

Quizplus · Accepted Answer

Option B is the only one which has the correct timeframe for both the appearance of the first mammals and the earliest primates. The first mammals appeared about 200 million years ago and the earliest primates appeared about 65 million years ago. Option A, C, and D have at least one incorrect timeframe, while option E has the correct timeframe for the earliest primates, but the first mammals appeared much earlier than 50 million years ago.

The First Mammals Appeared Over _______________ Years Ago and the Earliest