Chamaleon

Chameleons have specialized cells, chromatophores, which contain pigments in their cytoplasm, in three layers below their transparent outer skin:

1. The cells in the upper layer, called xanthophores and erythrophores, contain yellow and red pigments respectively.
2. Below these is a second layer of cells called iridophores or guanophores; these contain guanine, appearing blue or white.
3. The deepest layer of cells, melanophores, contain the dark pigment melanin, controlling how much light is reflected.

Dispersion of the pigment granules in the chromatophores sets the intensity of each color. When the pigment is equally distributed in a chromatophore, the whole cell is intensively colored. When the pigment is located only in the centre of the cell, the cell appears mainly transparent. Chromatophores can rapidly relocate their particles of pigment, thereby influencing the animal's color. Chromatophores change because the cells get a message from the brain.