Brittle Stars
Brittle stars are echinoderms that are related to the starfish, sea cucumber, sea urchin and sand dollar. Most brittle stars live in coral reefs and there are over 1,800 different kinds of species of brittle stars. Their bodies consist of five flexible and brittle arms stemming off of the mouth, which is a circular disk located at the center of the arms. Since their arms are very easily broken they are able to regenerate their own arms. On the bottom of each arm are tube feet, which are used for motion along the ocean floor. Brittle stars are believed to be omnivores, feeding on any organic material or small prey they can find.
They use bioluminescence on predators to scare them by flashing green light at the predators. The arms of most brittle stars tend to be small but are the only parts of the species that exhibits bioluminescence. Bioluminescence is thought to be used for defense, and courtship and mating in brittle stars. It may be caused by both environmental factors, such as the amount of metal in the surrounding area, and physiological factors in the nerves on the arms.
They use bioluminescence on predators to scare them by flashing green light at the predators. The arms of most brittle stars tend to be small but are the only parts of the species that exhibits bioluminescence. Bioluminescence is thought to be used for defense, and courtship and mating in brittle stars. It may be caused by both environmental factors, such as the amount of metal in the surrounding area, and physiological factors in the nerves on the arms.
