Unlike most birds, hummingbirds have iridescent feathers. Iridescent feathers and shine in the sun. Hummingbirds are often combinations of greens and reds or greens and blues. Others are violet, orange, golden, silver or other only Mother Nature could up. All hummingbirds have long bills to into flowers. Some hummingbirds have bills to in specific flowers. Hummingbirds are the only birds that can fly .