From the World of Wings, Beak & Feather
B irds are found on every continent of the world. Birds of different types can live in freezing cold environments, and others can live in hot deserts. Birds live in forests, in grasslands, on cliff faces, in river banks, on stony sea shores, down mine shafts and in the roofs of houses. Birds are a class of vertebrates & they live in the moment. A ll they do is revel in rushing air and vertical surfaces, trees that swoop up towards them, hot sun warming their hollow bones. . They feel the thrill of free flight and all that .They are warm-blooded and lay eggs. Birds are bipedal: they have two legs which are often covered with scales (small, flat plates which over-lap in the same way as feathers). They have a hard beak with no teeth. Their bodies are covered with feathers and they have wings. Feathers have three functions: flight, temperature regulation and display. Most birds have hollow main bones with air sacs in them. This makes them lighter and makes flight easier
