Welcome to the World of Hummingbirds by Diane Swanson

Did you know there are approximately 340 different kinds of hummingbirds, some as light as a penny? These champion acrobats of the sky can beat their wings more than 40 times a second, fly backward and even hover in midair, like helicopters. Since it's much easier to hear hummingbird wings than see them, just follow the hum to find the birds.