Which characteristic defines the Paleozoic era?(1 point)

Question

Responses

Simple, one-celled life forms were dominant.
Simple, one-celled life forms were dominant.

Reptiles became dominant after a mass extinction.
Reptiles became dominant after a mass extinction.

Animals with shells and hard parts were dominant for the first time.
Animals with shells and hard parts were dominant for the first time.

Mammals and other warm-blooded animals became dominant

Answer 1

The characteristic that defines the Paleozoic era is:

Animals with shells and hard parts were dominant for the first time.

This era, which lasted from about 541 to 252 million years ago, is known for the dramatic increase in diversity of life forms, including the development of hard-shelled organisms during the Cambrian explosion.