Free Cat Giving Middle Finger Svg SVG PNG EPS DXF File Bird anatomy, or the physiological structure of birds' bodies, shows many unique adaptations, mostly aiding flight.birds have a light skeletal system and light but powerful musculature which, along with circulatory and respiratory systems capable of very high metabolic rates and oxygen supply, permit the bird to fly. Dec 21, 2017 · the latest tweets from bleacher nation cubs (@bleachernation).