Animals create their colors through two main mechanisms: pigmentation and structural coloration. Pigments like melanin create browns and blacks, while carotenoids (often obtained from diet) produce yellows and reds. Structural colors are created when light interacts with microscopic structures in feathers, scales, or skin.
For example, blue jay feathers appear blue due to the way light scatters through tiny structures in their feathers, not because of blue pigment. Iridescent colors in peacock feathers and butterfly wings are also created through structural interference with light waves. Some animals, like chameleons, can actively change their coloration by altering the arrangement of specialized cells called chromatophores.