The Only Therapsid Group Which Survived to Enter the Mesozoic

Question

The only therapsid group which survived to enter the Mesozoic was the
A)cynodonts.
B)pelycosaurs.
C)sphenacodontines.
D)theropods.
E)mesopods.

Accepted Answer

Cynodonts were the only therapsid group that survived into the Mesozoic era, which began approximately 252 million years ago with the Triassic period. They evolved into mammals during the Jurassic period, which began approximately 201 million years ago. Pelycosaurs and sphenacodontines were earlier groups of therapsids that became extinct before the start of the Mesozoic era. Theropods were a group of dinosaurs that evolved from reptiles and did not have any direct connection to therapsids. Mesopods are not a known group of prehistoric animals.