Question

How is it that most, if not all, of the extant animal phyla today evolved during the Cambrian period if so many massive extinction events have taken place since then?

a) Because the Cambrian period was characterized by rapid speciation and diversification.
b) Because extinction events had no impact on animal evolution.
c) Because the Cambrian period followed the last mass extinction event.
d) Because most animal phyla evolved independently of environmental changes.

Answer 1

During the Cambrian period, the rapid diversification and evolution of animal species, known as the Cambrian explosion, led to the emergence of most of the animal phyla that exist today. Despite subsequent mass extinction events, some species of most animal phyla survived and continued to evolve.

Step-by-step explanation:

During the Cambrian period, there was a rapid diversification and evolution of animal species, known as the Cambrian explosion. This period witnessed the emergence of most of the animal phyla that exist today. Although there have been mass extinction events since the Cambrian period, some species of most animal phyla survived, allowing the phyla to persist and continue to evolve.