Bioluminescence

Distribution

The last censuses estimate at 90 the percentage of species living in the abyssals zone which produce bioluminescence of a form or another. The majority of the marine light outputs belong to the luminous Specter of the Bleu and the Vert, the wavelengths which can be transmitted easily through water. More rarely, certain species emit in the Rouge or the Infrarouge.

The not-marine bioluminescence is rarer but authorizes a more important variety of colors. The most known forms of terrestrial bioluminescence are the Lampyre S and the Luciole S but of faculties of bioluminescence were described at others Insecte S, Arachnide S or even at some Champignon S.

Function of the bioluminescence

There exist four principal theories for the evolution of the character of bioluminescence:

Camouflage

Although that can appear paradoxical, certain fish use the bioluminescence at ends of Camouflage. Indeed, with average depths, the predatory ones track their preys by lower part, the contour of the preys thus taking shape like Chinese Ombres in the weak light arriving of surface. Certain fish thanks to the bioluminescence produced on their ventral area (which simulates the light of surface) become artificially transparent with predatory located deeper.

Attraction

The bioluminescence can also be used like a Leurre by various abyssal species like some Lophiiformes. A Appendix luminous swing and extending to the top from the head from fish thus makes it possible to attract the small animals at a distance authorizing the attack.

The attraction of the sexual partners is another function of the bioluminescence. One finds it in particular at the Lampyre S which use a periodic flash on the level of their abdomen to attract their partner at the time of the reproduction.

The bioluminescent plankton, which one finds in clean water, as on the coasts north of Brittany close to Saint-Malo, in the reserves, in Corsica and in the south east of France: Porquerolles… Micro the organizations composing the plankton use the bioluminescence to be better seen fish: the fish, attracted by its lights arrive and the avalent one. The plankton reproduces more quickly in the abdomen of fish than in water around (presence of bacterium, higher temperature…) this is why it happens, that in these areas where water is rather pure, if one has fun to stir up water one can see there small bluish clouds which are formed there.

Repulsion

Some Calmar S and small shellfish use bioluminescent chemical mixtures (also muds of bioluminescent bacteria) in order to push back the attacks in predatory same way that many squids use the Encre: a cloud of luminescence is expelled diverting or pushing back a predatory potential thus allowing the squid or shellfish to escape in full safety.

Communication

The bioluminescence could also play a direct part in the communication between bacteria (see Quorum sensing). It also induces symbiosis between bacteria and a species host and could play a part in the aggregation of colony.

Types of bioluminescence

The bioluminescence can be divided into three principal types: an intracellular bioluminescence, extracellular and that of the symbiotic bacteria:

Intracellular bioluminescence

The intracellular bioluminescence is generated by cells specialized in the body of certain species Pluricellulaire S whose light is emitted towards outside through the Peau or is intensified by reflective lenses and materials (like the crystals of Urate of the Luciole S or the plates of Guanine of certain fish). This type of bioluminescence is that many species of Calamar.

Extracellular bioluminescence

The extracellular bioluminescence is carried out starting from the reaction between the Luciférine and the Luciférase, a Enzyme. Once synthesized, each component is stored in glands of the skin or under this one. The expulsion and the mixture of each reagent outside produced of the luminous clouds. This type of bioluminescence is common to some species of Crustacé S and to the abyssal Céphalopode S.

Symbiosis with luminescent bacteria

This phenomenon is only known in the marine animals like the Cténophore S, the Cnidaire S, the Ver S, the Mollusque S, the echinodermatous S and the Poisson S. It seems that it is the most widespread type of bioluminescence of the Animal kingdom.

At various places of the body, the animals lay out of small blisters, commonly called Photophore S which contain luminescent bacteria. Certain species produce light continues whose intensity can be neutralized or modulated by means of various structures specialized. The luminous bodies are generally connected to the Nervous system what makes it possible the animal to control the light output.

Use in biotechnology

The bioluminescence of the organizations is the target many fields of research. The use of the Luciférase is widespread in genetic Engineering like Gène marker.

Bacteria of the kind Vibrio in symbiosis with many Invertebrate S sailors or fish as Euprymna scolopes are a key experimental model in the study of the Symbiose S, the Quorum sensing and the bioluminescence.

In biotechnology, the bioluminescence allowed the development of the ATPmétrie. Indeed, the luciférase is also able to react with the Adénosine triphosphate (or ATP). It thus makes it possible to quantify the biomass in a sample thanks to an apparatus called Luminomètre which measures the luminous intensity.

In addition, the structure of the Photophore S is studied by the industry which considers various applications:

of the Christmas trees which do not require lamps in order to reduce the electric risks,
radiant trees on the edge of the Autoroute S in order to reduce electricity consumption,
plants which light when they should be sprinkled,
new methods to detect the bacterial contaminations of food
of new luminescent pets (rabbits, Souris, Poisson S…)

External bonds

Bioluminescence in the animals. Anne-Marie Bautz. Bulletin of the Lorraine Academy of Sciences 2005,44 (1-4).
bioluminescence. Why and how of the animals emit light?
Bioluminescence of the worms luisants.
bioluminescence in the animal kingdom. Bibliographical memory

Simple: Bioluminescence

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