Hummingbirds' unique up-stroke wing power enables them to move in all directions including upside down. Incredibly their wings move so quickly that they appear a blur when in flight and enable them sudden lift off and stops. Their inept legs (except for perching) compel them to fly a few inches instead of walking. Their high metabolism, heart rate and breathing induce them to eat high sugars (nectars and saps) and protein (insects and pollen) every 10 minutes.