perfect paragraph 6 - animal camouflage
Another species known as the cuttlefish is able to change the color of its body within a matter of seconds. The cuttlefish is a marine invertebrate that uses chromatophores to manipulate its skin color. Chromatophores are light reflecting cells that contain pigments surrounded by a circular muscle. By contracting and relaxing this muscle, the cuttlefish can control the amount of light entering its light reflecting cells and therefore control its color. The iridophore muscle layer is composed of protein and is responsible for reflecting the blue and green environment around the cuttlefish, while Yellow chromatophores (xanthophores) reflect a warmer-colored background (such as sand).  Using these muscle contractions, the cuttlefish can quickly change the color of its skin to blend in with its surroundings when it senses danger is near.