Whales are not fish. They are mammals. A mammal is an animal that has lungs and breathes air. They also have hair on their bodies. Whales are sea mammals that live in the sea. Whales give birth to babies. They are called calves. The females are called cows, and males are called bulls. The calves do not have any blubber. Blubber is a thick layer of fat under the skin. Dolphins are whales. They enjoy frolicking near ships at sea. A whale breathes through its blowhole. When it sleeps, it closes its blowhole very tightly. It is almost like it is holding its breath.