To be ecologically successful, however, this bioluminescence needs to be properly controlled. The organisation of the photophores strongly suggests that they are involved in varied behaviours, including anti-predatory response (camouflage) and intraspecies communication. It emits visible light from thousands of tiny epidermal photogenic organs – photophores – which are made of a cluster of photogenic cells called photocytes. The velvet belly lantern shark ( Etmopterus spinax) was used as a model for experimental studies on shark luminescence. However, shark luminescence works in a different way. Most fish bioluminesce by using their light organs (photophores) in one of two ways: harnessing the light produced by symbiotic bacteria or producing their own light through chemical reactions. The velvet belly lanternshark has served as a model species for shark luminescence research. Observations showed that the percentage of bioluminescent animals is remarkably uniform regardless of depth. A study by Martini and Haddock published earlier this year analysed 17 years of video footage taken from the sea’s surface down to a depths of almost 4000 metres. It is also worth noting that bioluminescence is not just exhibited by deep sea dwellers existing in perpetual darkness. At present the only known terrestrial animals capable of bioluminescence are arthropods, whereas in marine environments, bioluminescence has evolved from bacteria to vertebrates (Davis et al 2016). In fact, there are a known 29 independent evolutionary events of bioluminescence in marine fish lineages alone.īioluminescence in vertebrates is found exclusively among fishes living in marine environments. It is a phenomenon that has been documented in over 700 genera of animals, with the vast majority living in the ocean. In contrast to fluorescence and phosphorescence, bioluminescenct reactions do not require the initial absorption of sunlight or other electromagnetic radiation by a molecule or pigment to emit light. Trawl capture of Etmopterus spinax (velvet belly lanternshark) in the Mediterranean Photograph: Christopher Bird What is bioluminescence and what use is it?īioluminescence is the emission of light as a result of a biochemical reaction.

Picture dwarf lantern shark