How do you Know Dolphins are Mammals?

Dolphins are mammals because they breed their babies with milk produced by the mother.

They are also vertebrate and warm blooded which are common characteristics of mammals.

Also, they breathe air through their lungs.

Although they don't have long hair like most mammals, they still have tiny hair all over their skin.

Links to other pages in this site

How Smart Are Dolphins?
Why Baby Dolphins Swim So Close To Their Mother?
How Do Dolphins Help People?
Why Are Dolphins Dying?
What Are The Attraction To Dolphins?