Camouflage is frequently used in the animal kingdom in order to conceal oneself from visual detection or surveillance. In the late 1800's, an American artist named Abbott Thayer was the first one to make an important research on animals' protective coloration in nature, and that became a useful tool in developing modern camouflage.
There has been a long time for biologists to study camouflage, and the numerous examples found in the animal kingdom provided them with illustrations of ideas of natural selection and adaptation. The mechanisms of camouflage include background matching, disruptive coloration and self-shadow concealment via countershading (Thayer 1909; Cott 1940). The presence of diversity of camouflage strategies is important to avoid predation which is one of the most important selection pressures. With most examples, visual camouflage involving body coloration is usually used by animals to make detection or recognition more difficult.
As experts in the art of camouflage, cephalopods - octopus, squid, and cuttlefish - are more attractive to scientists to decipher the secrets. Cephalopods show an impressive skill of changing body patterns for camouflage and signaling almost instantaneously.