7 Pelvis Wing bones Backbone Neck Skull Back view of a crow’s skeleton Ulna Claw Radius Metacarpus Wishbone Lower leg bone (tibia) Thigh bone Ankle, or false knee Hind toe Humerus Pygostyle, bony stump to which tail feathers are attached Hip girdle Ulna Radius Humerus Backbone, made up of bones called vertebrae The bird skeleton The most prominent feature of the skeletons of flying birds is the keel – a projection from the breastbone that anchors the wing muscles. The forelimbs are adapted for flight, while the beak (or bill) is used for feeding and preening. Nostril Eye socket Upper beak Lower beak Cranium Ear Streamlined body Although they differ in size, flying birds like the crow all have a very similar overall shape. This is because they need to be streamlined and cannot afford structures that would make them weigh more. Keel Owls have remarkably flexible necks and can turn their heads more than 180° . Knee joint Metatarsus