Birds are animals with . They live everywhere on Earth, in cold and in warm climates . Some live near areas, others travel far inland. Flying birds can reach speeds of up to 160 kilometers an hour. However, not all birds fly. Ostriches are running birds and the wings of have turned into during the ages.

Birds belong to a group of animals we call , animals with backbones. They are -blooded, which means their body temperature always stays the same. Baby birds from their mother's eggs and stay in a nest for several weeks.

Birds have a strong skeleton and , lightweight bones. The strongest are in the wings , which they flap in order to fly. The bills or of birds can be different in size and shape. Woodpeckers have sharp, pointed bills which they use to holes into trees. Ducks have flat bills, so that they can eat in the water.

Most birds have a good of sight and large eyes. The ears are covered with feathers. Birds do not have a very good sense of smell, but some rely on their smell to get food.

Wings are on the top and flat on the bottom. Birds can fly because they use their wings to create air that lifts them upwards.

Birds are important for humans because they do a lot of things. They carry from one flower to another. Some birds , like chicken or turkeys, provide us with meat. Others, like , are kept as pets.

Many birds to get food and water throughout the year . They often travel thousands of kilometers and on the sun, the moon and the stars to help them find out where they are. When birds lose their sense of they get lost and fly to places far away from their normal .