Glass squid are animals who live in the dark sections of the ocean. There are about 60 species of Cranchiidae (glass) squid, and a number of these animals are almost invisible.
Glass squid spend most of their time hidden in the ocean; however, during their mating season, chromatophores show up on the squid like bright lights. These chromatophores attract other squid for the purpose of mating.
The glass squid is also called the cockatoo squid. The animal is able to float through the water by keeping solutions made of ammonia in its body that make it buoyant and give it a balloon-like shape.