There are sea creatures that behave very strangely. For example, did you know that there is a fish that spits light?
This may lead us to think of fire-breathing dragons. And because of that, some think that the fish spit light to defend themselves or even attack. But this is not so.
Actually the light that these fish spit is not theirs.
Why do cardinal fish spit light?
This curious phenomenon occurs when a cardinal fish eats a crustacean, to defend itself and avoid being devoured it emits a strong light that frightens the fish, which spits it out instantly. The beam of light comes out of its mouth, and it seems that the fish is spitting out light.
Thus the crustacean saves its life.
What would happen if the fish swallowed the crustacean even though it had emitted its light? Well, this would make the fish easy prey for its predators, since it would be shining everywhere, as if it had a huge neon sign with the word “eat me”. In the very dark places where the cardinal fish lives, this would be the end of it.
After spitting out the crustacean, the fish decides to walk away and go to a darker place.
The light emitted by the crustacean is produced when two chemical compounds come together, luciferin and luciferase. Light is thought to be blue because it is the color of the visible spectrum that travels the furthest through water waves.