#143 In the Field: Bird anatomy and sculpture workshop con't . . .

Human arm top, bird wing bottom

The skeleton of the bird's wing is more easily understood when compared to the human arm:

Humerus - Innermost bone, between body and elbow.

Ulna/Radius - middle or forearm bones, between elbow and wrist.  The secondary feathers are attached to the ulna.

Hand - Outermost bone, some metacarpals are missing, some are fused together.  One of the digits is the thumb or alula, a small group of three or four feathers are attached to the bone. The ten primary flight feathers (nine in some perching birds) are attached to the hand.  

Drawing of wing skeleton showing primaries, secondaries and tertials
by Sandy Scott