Bioluminescence, explained in a minute
Throughout evolution, all living organisms aim to develop traits that will give them an advantage. Like most astounding wonders in nature, bioluminescence is a crucial attribute to many life forms on earth.
By Bella Wang
What is bioluminescence?
Chemiluminescence is a chemical reaction that emits light. In living organisms, this process is called bioluminescence. In bioluminescent species, the required chemicals are either found on the / itself or provided by bacteria. For bioluminescence to occur, species must have luciferin, which, when oxidized, releases light.
Bioluminescent species can use their light-emitting abilities on demand. Some have photoprotein that can pre-package oxidized luciferin so that light can be called to action when a chemical is present. Other times, species can regulate when they want to glow up, such as when they decide to feed or mate.
Luminescence varies in appearance; it depends on the habitat and the organism that produces it. Bioluminescent species usually emit light on the lower end of the visible spectrum, such as blue or green. However, some species have also developed luminescence in colours such as yellow and red. In the ocean, higher frequency light is less visible because longer wavelengths cannot travel far. Thus, many marine organisms cannot process colours such as red, orange, or violet.
Importance
Studies have shown that luminescence has evolved over 40 separate times! These adaptions occur for numerous reasons, including for defence, offence, and attraction. In fact, in such a vast place like the ocean, bioluminescence might also be a form of communication.
1. Dragonfish
To animals like the dragonfish, bioluminescence is extremely useful in more ways than one. Being able to glow a red colour, they are practically invisible to predators; and prey on other red animals in the ocean with little to no competition. Additionally, dragonfish use bioluminescence to communicate with other dragonfish.
2. Dinoflagellates
Bioluminescence is not only found deep in the oceans. Some bioluminescent organisms live on the ocean’s surface, like dinoflagellates. Occasionally at nighttime, bioluminescent dinoflagellates can be spotted, lighting up the water’s surface. Being microscopic plankton, some use this ability to scare off predators as well!
3. Fireflies
Bioluminescence does not only appear in the ocean. Fireflies are, likely, the most well-known bioluminescent species. We often imagine millions of blinking lights on a summer evening when we think of fireflies, but what is happening during that scene? Well, these fireflies are trying to find mates. Although all fireflies are bioluminescent, the males have flashing lights. These lights convey what species they are and that they’re essentially single.
Superpower, indeed!
Although producing light ourselves might be impractical to us, it is vital to many species. What makes this power intriguing to us is bioluminescence affects many species and how they live even though the evolutionary paths many took were completely different.