The beginning of the Phanerozoic is marked by the ________.
A)evolution of land plants and animals
B)development of hard body parts,such as shells and bones
C)abundant life forms compared to earlier times
D)formation of large land masses
E)existence of a modern atmosphere

Question

Quizplus · Accepted Answer

The beginning of the Phanerozoic eon, which began around 540 million years ago, is marked by the development of hard body parts in organisms, such as shells and bones. This allowed for the diversification and expansion of life forms in the oceans and on land.

The Beginning of the Phanerozoic Is Marked by the ________