He cut the apple.

He rejoiced when he heard about the success.

He is an expert in ethology.

Chrysophyta perform photosynthesis underwater.

Chrysophyta are living in this pond.

He is an expert in nuclear physics.

He is immersed in the study of dialectical materialism.

As the name suggests, chordates are a group of animals that have a notochord.

He is deeply involved in the animal liberation movement.

We went to the petting zoo on the weekend.