Pigment-containing and light-reflecting cells, or groups of cells, found in a wide range of animals, including amphibians, fish, reptiles, crustaceans and cephalopods. Researchers from the University of Bristol
have created artificial 'skin' that can copy squid's ability to instantly change colour. The material could be used in smart clothing or fabrics that would be able to change colour similar to camouflaging tricks witnessed in nature.