Question

Describe three skeletal adaptations that allow for flight in birds.

a) Increased bone density, feathers, and long legs.
b) Light and hollow bones, wings, and keeled sternum.
c) Scales, reduced bone density, and long tail.
d) Gills, elongated neck, and webbed feet.

Answer 1

Three skeletal adaptations for flight in birds are light and hollow bones, wings, and a keeled sternum, all of which enable reduced body weight and attachment of flight muscles.

Step-by-step explanation:

The three skeletal adaptations that allow for flight in birds are light and hollow bones, wings, and a keeled sternum. The lightweight structure is essential for flight, and this is achieved through modifications such as pneumatization of bones. Pneumatic bones help reduce the bird's body weight, essential for flying animals. These bones are hollow and contain cross struts of bone called trabeculae, which provide structural reinforcement while keeping the bones light. The wings of a bird are modified front legs that are used for flying, which attach to large muscles in the bird's chest. A bird's keeled sternum is a bony ridge along the breastbone to which the flight muscles attach, allowing for ample muscle mass and the stability required for flight.