The quagga is an extinct animal.

This species is on the brink of extinction.

That species is on the verge of extinction.

I saw many animals at the zoo.

We went to the zoo with our family on the weekend.

Vertebrates are organisms whose part of the skeleton is composed of a spine.

Wild animals are part of nature, and we should protect them.

He is majoring in zoology at university.

She has zoophobia, and runs away as soon as she sees dogs or cats.

Animal experiments are necessary for the advancement of science, but there are also ethical issues.