World-wide, people have marveled at the flashing lights of fireflies on warm nights. These beetles are called many names: blinkies, glowworms, moon bugs, and lightning bugs. All these names reflect the quality of fireflies’ bioluminescence to communicate.
These remarkable insects have the most efficient light in the world. Their “cold light” consists of the luciferase enzyme which acts on the luciferin in the presence of magnesium, ATP, and oxygen. The adults flash to speak with each other and to find mates. Even firefly eggs and larvae glow, as a warning to predators. They tell predators that they taste lousy.
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