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 boreal climates often need snow camouflage, either by having reversible uniforms or simple overgarments. Such simple overgarments can be used for other terrains too. The Austrian and Israeli armies use solid colour field uniforms, relying on simple overgarments for camouflage. The purpose of vehicle and equipment camouflage differs from personal camouflage in that the primary threat is aerial reconnaissance. The goal is to disrupt the characteristic shape of the vehicle, to reduce shine, and to make the vehicle difficult to identify even if it is spotted. Paint is the least effective measure, but forms a basis for other techniques. Military