On the biophotonic properties of brittlestar ossicles

Brittlestars (Echinoderms) are a large group of marine invertebrates, from which many species are able to produce bioluminescence. The light is used for ecological functions associated with defense. Hence, the larger and more intense the bioluminescent display the more effective it would be. Here, we report on our study to determine whether ossicles, making the arms of brittlestars, play a role in increasing the luminous display. We compared ossicles from three brittlestar species, two luminous and one not, and found no striking difference between the ossicles, in terms of structure, or calcium and magnesium content.