Question

What was the first period of the Paleozoic era?
1.Siberian
2.Precambrian
3.Ordovician
4.Cambrian

Answer 1

4. Cambrian period period was the first of the Paleozoic era

Answer 2

The correct answer is (d) Cambian

The first period of Paleozoic era was Cambian period which lasted from 541 million years ago to 485 million years. This period was marked as a boom in evolutionary history by the event named as Cambrian Explosion. In this event a large number of creatures evolved in any single period of the Earth. creatures like algae and arthopods like trilobites. All the marine phyla also evolved during this period.