Hummingbirds are birds native to the Americas and comprise the biological family Trochilidae. Did you know that the color of these cute birds changes depending on their diet? One study of hummingbirds discovered that dietary protein is an influential factor in feather color, as birds receiving more protein grew significantly more colorful crown feathers than those fed a low-protein diet. Thus, birds on a high-protein diet become yellower with green tail feathers. The bird from our Yellow Hummingbird Pixel cursor pack had a rich protein diet.