Burning Bright: Avian Adaptations for Flight

S1 E3: Discover the remarkable physiological features of birds that undergird flight. First, note how and why feathers evolved. Then, investigate the high metabolism of birds - they must burn energy at an astounding rate. See how birds are adapted for flight by many weight-reducing factors, and how their respiratory, circulatory, and excretory systems, as well as heightened senses, keep them airborne.