The chameleon is a reptile from the lizard family, found in Asia, Africa and Europe. It is famous for its ability to change colour. The chameleon has transparent skin on its outer surface. Beneath this are layers of pigment-containing cells called chromatophores. The top layers of chromatophores have yellow pigment, while the lower layers have red and blue pigment. The chromatophores are connected to the nervous system. On getting a signal from the brain, the pigment in the chromatophore spreads, and the chameleon’s skin colour changes. By varying the relative amount of activity of the different chromatophores in different layers of the skin, it is like mixing different paints together. This is how chameleons change into a wide variety of colours and that too, in less than a minute. People believe that chameleons change colour as a form of camouflage, that is, to blend in with their surroundings.
However, scientists disagree. Their studies have found that light, temperature, and mood cause chameleons to change colour. For instance, while resting in the sun, a brown chameleon might turn green because this lighter colour would help the skin reflect bright sunlight. Similarly, in cold weather, a chameleon might choose a dark colour as darker colours absorb more heat than light ones. Further, the chameleon also changes its colour to show its mood – when angry, it goes bright yellow, and while wooing a mate, it chooses bright, flashy colours.
