Question

The CORRECT sequence of ancestors of mammals starting from the oldest is:

• A. Sauropsida $ \rightarrow $ Pelycosaurs $ \rightarrow $ Therapsida
• B. Synapsids $ \rightarrow $ Pelycosaurs $ \rightarrow $ Therapsida
• C. Synapsids $ \rightarrow $ Therapsida $ \rightarrow $ Pelycosaurs
• D. Pelycosaurs $ \rightarrow $ Therapsida $ \rightarrow $ Synapsids

Answer 1

Answer: (B)

Mammals evolved from reptiles. There have been many stages of development in these mammals. The main ancestors that evolved from reptiles are the Synapsids and Sauropsids. Sauropsids evolved into turtles and Synapsids into mammals. These then evolved into Pelycosaurs which finally evolved into Therapsids. These then formed the mammals. Thus these three are the main ancestors of mammals.