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
Camouflage viper.Military uniforms, too, generally resemble their backgrounds; for example khaki uniforms are a muddy or dusty colour, originally chosen for service in South Asia.Many moths show industrial melanism, including the peppered moth which has coloration that blends in with tree bark. The coloration of these insects evolved between 1860 and 1940 to match the changing colour of the tree trunks on which they rest, from pale and mottled to almost black in polluted areas. This is taken by zoologists as evidence that camouflage is influenced by natural selection, as well as demonstrating that it changes where necessary to resemble the