Last week we looked at a strange looking deep sea creature, the Frilled Shark. This week we are looking at another deep sea shark that also has to deal with the stresses of living in the deep sea. This week’s Creature Feature is the illuminating Velvetbelly Lanternshark (Etmopterus spinax).
As we discussed last week, one of the big challenges down in the deep is the of lack of light. We know that food is hard to come by in the dark, but it can also be really hard to find a mate! Some people might say such a thing is challenging enough in the daylight, but this shark knows how to attract a mate. Like many other deep sea organisms this shark is bioluminescent. You should recall that bioluminescence is the production and emission of light by a living organism. The Velvetbelly’s amazing light emission is produced by a chemical reaction between a protein called luciferin and an enzyme called luciferase which react when oxygen is present.
Velvetbelly Lanternsharks have a highly unique light pattern, the chemical reaction of which takes place within the photophores (light-producing organs). The photophores of this shark are positioned along the lateral line, under the snout and chin, and over the belly – but not around the mouth. Many believe that these photophores have strategic chemical reactions, emitting specific light patterns intended to attract Velvetbellies to mate, lure food, and to hide from predators.
There are still many gaps in the information we possess about deep sea organisms. With current studies in submersibles, new creatures have been discovered and information about this habitat and its inhabitants are growing.
Join us next week as we look at another uncommon deep sea shark.
Edited by KC O’Shea
Image from http://www.divernet.com/Marine-Life/951170/quest_for_the_lanternfish.html
Claes, J. M., Ho, H.-C. and Mallefet, J. (2012). Control of luminescence from pygmy shark (Squaliolus aliae) photophores. J. Exp. Biol. 215, 1691–1699.