This cave is rich in guano.

His actions are as meaningless as a rotten wood and dung wall.

He is truly an eccentric person.

He is acting like a fool.

The number of visitors to the park today is higher than yesterday.

Cnidarians are a type of marine life, including jellyfish and corals.

The ecosystem of zoobenthos is an important field of study in marine biology.

Echinoderms are a type of marine life, many of which have star-shaped bodies.

The characteristic of annelids is that their bodies are divided into ring-shaped segments.

A tardigrade can survive in extreme environments.