Coelenterates are said to be the first animals with a true body cavity.

His tribe has been practicing zoolatry since ancient times.

He is studying about ancient animal worship.

Chrysophyta perform photosynthesis underwater.

Chrysophyta are living in this pond.

He is an expert in nuclear physics.

He is deeply involved in the animal liberation movement.

We went to the petting zoo on the weekend.

This area is affected by radioactive fallout from past nuclear tests.

The study of nekton is an important part of marine biology.