Imagine a dark, moonless night when you have gone camping with your classmates and you lose your way. What would you do? Will you not try contacting your friends by flashing your torchlight?
Well, fireflies or ‘lightning bugs' as they are sometimes called do the same, except that they have an unlimited supply of light within themselves! That is why fireflies never worry about fused light bulbs or electricity tariffs. They seem immensely happy just flying around and glowing- this is their signal to say, "Hey, look! I'm here!"
The glow of the firefly is produced by a protein called luciferase and a pigment called luciferin. Proteins are special food used by our bodies to create muscles, bones and skin while pigments are natural coloring substances found in plants and animals. When these two meet inside the tiny belly of the firefly, they react with the oxygen already found in there.
A celebration takes place, a soft firework display, so to say and bright light is produced which is the ‘glow' of the firefly! Fireflies therefore are bioluminescent but they are not the only ones. Different types of fish and marine creatures in the sea also produce their own lights!

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