Wings:
1. Asymmetrical Flapping: Birds can flap their wings asymmetrically, meaning they flap one wing more forcefully or at a different angle than the other. This creates an unequal lift, causing the bird to turn in the desired direction.
2. Wing Shape Modification: Birds can adjust the shape of their wings by spreading or folding their primary and secondary feathers. By manipulating the wing's camber (curvature), they can generate more lift on one side of the wing, resulting in a change in direction.
3. Altered Wing Angle: Birds can change the angle of their wings relative to their body. Tilting the wings upward increases lift, allowing the bird to climb or reduce speed, while tilting them downward generates more thrust for acceleration or dives.
Tail Feathers:
1. Tail Orientation: Birds can move their tail feathers to steer and change direction. By twisting or fanning out their tail, they can create directional control surfaces that help in making tight turns or maintaining stability during flight.
2. Variable Tail Length: Some bird species have long, graduated tail feathers, which provide increased maneuverability. These feathers act as rudders, helping the bird make precise turns and adjustments mid-air.
In addition to wing and tail movements, birds also use their body positioning and flight muscles to coordinate and execute direction changes. They may tilt their bodies, extend their legs, or modify their wingbeat frequency to achieve desired flight changes. Overall, a combination of these adaptations allows birds to change directions gracefully and efficiently in the air.