How do fireflies glow?

The firefly’s glow is called bioluminescence [by-oh-loo-muh-nes-uhns]. Bio means living and lumin means light. This “living light” is created by a chemical reaction inside the fireflies’ bodies. In the reaction, two chemicals mix with oxygen to create light.

In parts of North America, the blinking lights of fireflies are a common sight in the spring and early summer. Each species uses a different rhythm of flashes. Fireflies use their flashing lights to find mates and to recognize members of their species.