A study of the mechanism of claw retraction in a cat. This is another of those aspects of cat biomechanics that I really needed to draw in order to fix it in my mind. Once you see how this works you understand that we should not talk so much about “retractable” but about “protractable” claws. Retracted is the normal, relaxed position of the claws, and active contraction of several muscles is needed for the animal to deploy its weapons.