A variety of fish and cephalopods use tunable 1 D photonic crystals to signal and display information. These animals control the color of the reflectors through chemical secretion by the sympathetic nervous system, which reduces the distance between platelets in reflective cells. This control can be mimicked by a bioinspired, 1D photonic block copolymer that is made tunable (see figure) by the production of chemical species through electrochemistry.