Bioluminescence is a phenomenon of living beings emitting light. It is a very common phenomenon, although, in many cases, the light emitted by the living organisms is not visible light. The classic example of organisms emitting visible light is a firefly or jellyfish. Discover illuminating facts about bioluminescence –
How Does Bioluminescence work?
The fireflies emit light due to the presence of luciferin. This compound is found in their abdomens. “Luciferin” means “light carrier” in Latin. The greenish yellow glow is produced as a result of the reaction of air with the compound Luciferin. This reaction is called “chemiluminescence”. This reaction is 100% efficient. It releases no heat and only produces light. If it had produced as much heat as our light bulbs do, the fireflies would incinerate from their own heat.
Why do animals and plants show bioluminescence
In the case of fireflies, bioluminescence is usually used to attract the opposite sex. Fireflies also use it as a defense mechanism to confuse the predators.
Bioluminescence in deep sea creatures is due to the presence of symbiotic bacteria in their photophore cells.
Deep sea fish like anglerfish, viperfish and, monkfish use bioluminescence to attract its prey. Their bioluminescent cells are attached to a dangling appendage hanging from their head. Since these fish live in deep sea darkness, the prey is easily attracted towards them.
Another fish, lanternfish uses bioluminescence to hide its silhouette from predators. A lanternfish’ bioluminescent cells are found under its body.
Some squids found in deep sea beds use bioluminescence as a camouflage.
Types of bioluminescence
There are two types of bioluminescence
The intracellular bioluminescence is generated by specialized cells of the own body of some multicellular or unicellular species whose light is emitted outside after passing through their skin which can intensify the light.
While extracellular bioluminescence is generated outside the body of the organism due to the oxidation of Luciferin.
Different animals showing bioluminescence
Organisms that emit light include bacteria, fungi, hydras, jellyfish, anemones, polyps.
While larger species include some insects, worms, mollusks, crustaceans, echinoderms, and fish.
Certain species of sharks use bioluminescence to camouflage their lower part, appearing a small spot near their pectoral fins which remains dark. This results in fish being unaware of the shark’s presence.
It is believed that more than 90% of the animals living in the middle and abyssal portion of the ocean show some type of bioluminescence.