Mammals in the Sea
Most kinds of mammals live on land. But seals, whales, and a few other mammals live in the sea. They can stay underwater for a long time, but these mammals breathe air through their lungs. They rise above the water to breathe.
Whales look so much like fish that many people think they are fish. But they are mammals. They have hair, they are warm-blooded, and their babies drink mother’s milk. Dolphins and porpoises are small whales.
Seals, sea lions, and walruses are mammals that spend much of their time in the water and some time on land. When they come onto land, they waddle about on their fins.
Another group of sea mammals includes dugongs and manatees, which are sometimes called sea cows. These animals look a bit like walruses without tusks. Instead of hind flippers, each of these animals has a wide, flattened tail.
Picture Credit : Google