Question

Which is the correct sequence of ancestors in the path of primates evolution?

• A. $Crossopterygian\to Cotylosaur\to Therapsid\to Labyrinthodont\to Insectivors\to Primates$
• B. $Labyrinthodont\to Cotylosaur\to Therapsid\to Crossopterygian\to Insectivors\to Primates$
• C. $Crossopterygian\to Therapsid\to Cotylosaur\to Labyrinthodont\to Insectivors\to Primates$
• D. $Crossopterygian\to Labyrinthodont\to Cotylosaur\to Therapsid\to Insectivors\to Primates$

Answer 1

Answer: (D)

Crossopterygian evolved in the Paleozoic Era, Devonian period. These were the first Ray-finned and lobe-finned fishes.

Then the first land tetrapod vertebrates evolved which were Labyrinthodont amphibians.

In the Paleozoic Era, Carboniferous period, first reptiles which were the stem reptiles, the Cotylosaurs evolved from which all other reptiles evolved.

In the Paleozoic Era, Permian period, there occurred an increased diversity of reptiles and insects which evolved into mammal-like reptiles called Therapsids.

In the Paleozoic Era, Mesozoic period, first insectivorous mammals appeared. In the Cenozoic Era, Paleocene Epoch, primates appeared.

Hence, the correct sequence of ancestors in the path of primates evolution is :

Crossopterygian→Labyrinthodont→Cotylosaur→Therapsid→Insectivores→Primates

So, the correct answer is C.