Camouflage the peacock flounder, squid and octopus actively change their skin patterns and colours using special chromatophore cells to resemble their current background, or, as in most chameleons, for signalling. However, Smith's dwarf chameleon does use active colour change for camouflage. Each chromatophore contains pigment of only one colour. In fish and frogs, colour change is mediated by the type of chromatophores known as melanophores that contain dark pigment. A melanophore is star-shaped; it contains many small pigmented organelles which can be dispersed throughout the cell, or aggregated near its centre. When the pigmented organelles are dispersed, the cell makes a
Multi-scale camouflage times longer to detect than older NATO camouflage which worked at only one scale, while recognition, which begins after detection, took 20 percent longer than with older camouflage. Fractal-like patterns work because the human visual system efficiently discriminates images which have different fractal dimension or other second-order statistics like Fourier spatial amplitude spectra; objects simply appear to pop out from the background. Timothy O'Neill helped the Marine Corps to develop first a digital pattern for vehicles, then fabric for uniforms, which had two colour schemes, one designed for woodland, one for desert. Multi-scale camouflage Multi-scale camouflage is a type of