Active camouflage the surface, so when marine animals are seen from below, they appear darker than the background. Some species of cephalopod, such as the eye-flash squid and the firefly squid, produce light in photophores on their undersides to match the background. Bioluminescence is common among marine animals, so counterillumination may be widespread, though light has other functions, including attracting prey and signalling. Color change permits camouflage against different backgrounds. Many cephalopods including octopuses, cuttlefish, and squids, and some terrestrial amphibians and reptiles including chameleons and anoles can rapidly change color and pattern, though the major reasons for this include signalling, not
Military camouflage mimetico in Italy and the angular Splittermuster 31 in Germany. During the War, both patterns were used for paratrooper uniforms for their respective countries. The British soon followed suit with a brush-stroke type pattern for their paratrooper's Denison smock, and the Soviets introduced an "amoeba" pattern overgarment for their snipers. Hugh Cott's 1940 book "Adaptive Coloration in Animals" systematically covered the different forms of camouflage and mimicry by which animals protect themselves, and explicitly drew comparisons throughout with military camouflage: Both British and Soviet aircraft were given wave-type camouflage paintwork for their upper surfaces throughout the war, while American ones