The Engines of Flight

Avian flight muscle is like an engine with a large stroke—developing tension over a much longer relative muscle length than human muscle. This allows a large amplitude wing-flapping motion.

The main flight muscles shown schematically in a common pigeon—Rock Dove (Columba livia)>

The main flight muscles shown schematically in a common pigeon—Rock Dove (Columba livia)

Four muscles—two on each side of the chest (the “depressors”)—are the major engines that power the downstroke of a bird’s wings. They form the breast of the bird and you have probably carved and eaten them from a chicken or turkey. Two smaller muscles (the “elevators”) raise the wings, working through a groove over the shoulder. This smaller size reflects the fact that wing-raise can be assisted by drag on the outstretched surface. Opposing muscles are not usually on the same side of a joint but this arrangement keeps the bird’s center of gravity below the wings like a high-wing airplane. This increases flight stability.  Different birds have various combinations of slow and fast flight muscles depending on their lifestyles.

LEARN MORE ABOUT THE ENGINES OF FLIGHT

KIDS QUESTION:
In the Museum exhibit, wee asked: When you eat turkey breast, what part of the bird are you eating?

The answer is: The flight muscles of the Turkey
The flight muscles of the Turkey that are called the pectoralis major and minor (the wing depressors) and supracoracoideus (the wing elevator).