A bird’s body is specially adapted to help it fly. The most important body parts are the wings, but there are other features of a bird’s body that helps it fly.
A bird has hollow bones to make them light. They also have powerful flight muscles and a strong heart and lungs to provide the oxygen needed to power these muscles.
A bird’s wing works in similar way to an aircraft’s wing. They are a particular shape which is called an aerofoil. Because of the shape of the aerofoil, air flows over and under the wing at different speeds. Slower air flowing under the wing produces lift. While the faster air flowing over the wing produces drag.
When a bird flaps its wings the rotation of the wing with the lift propels the bird forward in flight. This is called thrust.
Photo credit: Milan Bruchter via 123rf.com
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