Turn to page 6 What's the difference between sharks and dolphins? Well, although sharks and dolphins look alike, they belong to two very different animal groups. The sharks are a kind of fish, but dolphins are members of another group. They're called the mammals. You don't look anything like a dolphin, but you are a mammal too. If an animal breathes air through lungs and its babies feed on their mother's milk, it's a mammal. Most mammals have some fur or hair on their bodies. If an animal has feathers and hatches out of a hard-shelled egg, it's a bird. All birds have wings and most of them can fly. If an animal has six legs and three parts to its body, it's an insect. There are more kinds of insect in the world than all the other kinds of animals put together. If an animal has damp, slimpy skin and is born in water, but lives much of its life on land, it's an amphibian. Baby amphibians hatch out of jelly-like eggs. If an animal has a dry, scaly skin and is born on land, it's a reptile. Most reptiles lay eggs with leathery skins. If an animal lives in water, breathing through gills and using fins to move, it's a fish. Most fish lay jelly-like eggs which hatch into baby fish.