Why do some animals have bright colours?

Bright colours in animals can serve several purposes, including attracting mates, warning predators, and blending into their environment. For example, many tropical birds and fish have vivid colours to attract mates, as bright hues often indicate health and good genes. In other cases, such as with poison dart frogs or monarch butterflies, bright colours act as a warning to predators that the animal is toxic or distasteful. Camouflage also uses colour to help animals blend with their surroundings, like the green of a grasshopper blending into leaves.