Now let's move on to explore the wrist joint.

First let's think about how a human wrist moves.

Place your right hand, palms down, on the desk in front of you.

Note the position of your index finger.

Keeping your arm still and your hand flat, rotate your fingers to the right as far as they will go.

The distance that your index finger moved defines the range of motion of your wrist.

The range of motion of your wrist is restricted by your wrist bones.

Now compare the range of motion exhibited by your wrist, and the wrist of a bird in flight.

The range of motion is greater for the bird.