Question

What is the Cambrian explosion? 1. The extinction event that wiped out the dinosaurs 2. The time when life on Earth first began 3. A period marked by a rapid increase in the diversity and complexity of life forms or 4. A volcanic eruption that occurred 540 million years ago

Answer 1

The Cambrian explosion refers to **3. A period marked by a rapid increase in the diversity and complexity of life forms**. It occurred approximately 541 million years ago, during the Cambrian period, and is notable for the emergence of many major groups of animals and the development of new biological forms and structures.