It’s not a teeny-weeny lightbulb or a spark that lights up a firefly’s insides. In fact, this insect’s fiery glow doesn’t produce any heat at all. It’s the product of a chemical reaction inside the bug’s body. By mixing chemicals and oxygen, the firefly switches its night-light on and off and controls its intensity, providing mood lighting for summer evenings in the backyard.
Fireflies are born with their built-in night-lights. They glow as larvae to warn predators not to eat them (firefly bodies contain yucky-fasting chemicals; one taste teaches mot predators to snack elsewhere). In their adult forms, fireflies flash to identify each other and attract mates. Female fireflies go for guy flies with the brightest, flashiest light show.
Picture Credit : Google