A scientist who studies birds is called an ornithologist.
Most birds can fly.
Birds have a very strong heart and an efficient way of breathing - these are necessary for birds to fly. Birds also use a lot of energy while flying and need to eat a lot of food to power their flight. The ability to fly has developed independently many times throughout the history of the Earth. Flying, Running, and Swimming The fastest running bird is the ostrich, but it cannot fly. The ostrich is also the fastest two-legged runner of all the animals on Earth.