Comp Biochem Physiol B 86: 411-417ĭenton, EJ Herring, PJ Widder, EA Latz, MF and Case, JF. References and Additional Reading: Campbell AK, Herring PJ (1987) A novel red fluorescent protein from the deep sea luminous fish Malacosteus niger.

Not only does the antenna pigment function like a plant's chlorophyll, harvesting energy from photons, but it actually is a derivative of chlorophyll!

By capturing the energy in this way, this sensitizing pigment can transfer theĮnergy to the visual pigments, which are usually only sensitive to blue-green light. In this figure (adapted from Douglas, et al., 1998) the sequence of events moves from right to left.Įach colored area shows the wavelength of light which is either emitted (red) or absorbed (yellow, green, blue).įirst, the red light emitted by the fish is absorbed byĪ special molecule which acts like an antenna. If the image is not animated, try reloading it. So the way they see the red light is even more complicated.Ĭonverting the red light back into visible light by a sort of 'reverse fluorescence', illustrated below. Their eyes only have visual pigments capable of detecting blue and green light (the blue and green graphs below). In the genus Aristostomias the solution is perhaps what you might expect: the fish bears an additional set of photoreceptive pigments, which can pick up light in the red region.įish in the genus Malacosteus, however, show no sign of having these special photoreceptors. It turns out that even this specialized problem has been solved in two different ways. The sea, the light is also filtered until it has a wavelength of around 705 nm.īecause most fish do not have a visual pigment which is sensitive to red (705 nm) light, the Malacosteidae must have an additional adaptation to make them sensitive to the red light. This light is absorbed by a fluorescent pigment inside the photophore, which takes the energy and re-emits it as red light (wavelength = 626 nm). Initially the light has a short wavelength (red is long-wavelength light). Light in the photophore (a light-producing organ) doesn't start out deep red.

To produce red light, the Malacosteidae use a combination of filters and fluorescent material. First, it has to produce red light, and then it has to be able to see it. There are two problems that need to be solved for the fish to make use of its 'night vision'. So these fish produce a red signal meant only for themselves, and a blue-green signal, perhaps used as a warning to others. The prey or any potentially curious predators. Although the light doesn't travel very far, it lets them see their prey, without alerting The ability to produce red light, gives the Malacosteidae a huge advantage in the deep sea. In addition, they can produce typical blue-green light from a separate organ. The light produced by species like Malacosteus, Aristostomias, and Pachystomias has such long wavelengths that it is nearly infrared and is barely visible to a human eye. The second reason for bioluminescence to be blue is that most organisms are sensitive only toīlue light - they lack the visual pigments which can absorb longer (yellow, red) or shorter (indigo, ultraviolet) wavelengths.Ī notable exception to this 'rule' is Malacosteid family of fishes (known as Loosejaws), which produce red light and are able to see this light when other organisms can not. The reason that underwater photos usually look blue is because red light is quickly absorbed as you descend. This page explains how and why it uses this amazing adaptation.Īlmost all marine bioluminescence is blue in color, for two related reasons.įirst, blue-green light (wavelength around 470 nm) transmits furthest in water. BL Web: Malacosteid Fish and Red Luminescence | T h e B l a c k D r a g o n f i s hĭeep-sea fishes carries around its own 'night vision' ability.

Deep sea glowing fish