Why are hummingbirds colorful?

Hummingbirds are colorful primarily due to the microscopic structure of their feathers, which refracts light and creates iridescent hues. This vibrant coloration plays a crucial role in attracting mates and deterring rivals, as bright colors often signal health and vitality. Additionally, their colors can help with camouflage among flowers and foliage, aiding in their foraging for nectar. Overall, their striking appearance is a combination of evolutionary advantages related to reproduction and survival.