Why was the Cambrian Explosion an important event in the evolution of life on the Earth?
A) This is when life first appeared on the Earth.
B) This is when multicellular life forms evolved.
C) This is when a great variety of invertebrates with shells appear in the fossil record.
D) This is when plants and land animals first occurred.

Question

Quizplus · Accepted Answer

The Cambrian Explosion was a period of rapid diversification of life around 540 million years ago, characterized by the appearance of a great variety of new invertebrate species with hard shells, such as trilobites, brachiopods, and mollusks. This event marked the first time in the fossil record that we see a significant increase in the variety of complex, multicellular organisms, setting the stage for the subsequent evolutionary radiation of life on Earth. While life certainly existed prior to this time - and there is evidence of earlier, simpler multicellular organisms - the Cambrian Explosion represents a major milestone in the evolution of complex life.

Why Was the Cambrian Explosion an Important Event in the Evolution