Hummingbirds are some of the most beautiful, tiniest birds in nature. They are the only creatures that can fly forward, backward, sideways—even upside down! Their hearts beat anywhere from 500 to 1200 times every minute; their wings flap as many as 52 times per second; and they breathe up to 600 times per minute. This fact-and-photo-filled nonfiction 8x8 will leave readers astounded by the smallest bird in America!