Tiny hummingbirds maintain their manic lifestyles by feeding on the sugary nectar within flowers. The bee hummingbird holds the record as the smallest living bird, at only 5-6 centimeters (2-2.5 inches). The birds burn energy quickly as they beat their wings up to 70 times per second in normal flight.
Plants attract hummingbirds using bright orange and red flowers with little odor. Hummingbird-pollinated flowers ooze extremely sugary nectar -- averaging 26 percent sugar, double the amount of a soft drink -- according to the Smithsonian National Zoo. Some flowers evolved to force a hungry hummingbird to brush its head on the pollen-laden stamens, a part of the flower. This turns the bird's head into a pollen postal service as the bird flits from flower to flower.