Because whales live in the ocean, many people think they are fish. But do you know that whales and dolphins are not fish? They are mammals. People are mammals too. Mammals are the group of animals that breath air using lungs, give birth to live young rather than laying eggs, and feed their young with motherââ¬â¢s milk. All animals, including people, need oxygen, a chemical found in the air and in water. Fish use their gills to take oxygen from the water that they live in. But people get the oxygen we need by breathing air, using our lungs. Whales and dolphins use their lungs to breathe air also. Thatââ¬â¢s one reasons why they come to the surface of the ocean. Sometimes they lie right at the surface of the water, with just a part of their back sticking out. Look closely at a picture of a whale or dolphin; can you see a nose on the whale? You canââ¬â¢t, because whales donââ¬â¢t have noses like you and me. Instead they have a hole ââ¬â called a ââ¬Åblow holeââ¬Â ââ¬â on top of their heads. Sometimes when a whale breathes air out of its blow hole, it shows up as a spray or mist ââ¬â called a ââ¬Åspoutââ¬Â ââ¬â that can be seen many miles away. Blow holes are surrounded by muscles that keep the hole closed when the whale or dolphin is under water and open it when the animal is at the surface and needs to breathe.
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