sentences:  The airfoil of the bird wing is made of feathers, strongly attached to the forearm (the ulna) and the highly fused bones of the wrist and hand (the carpometacarpus), with only tiny remnants of two fingers remaining, each anchoring a single feather.So, while the wings of bats and birds are functionally convergent, they are not anatomically convergent.Birds and bats also share a high concentration of cerebrosides in the skin of their wings.