Bioluminescence Bioluminescence Bioluminescence is the ability of living things to emit light. The molecular details vary from organism to organism, but each involves a luciferin , a light-emitting substrate a luciferase , an enzyme that catalyzes the reaction ATP , the source of energy molecular oxygen, O 2 The more ATP available, the brighter the light. In fact, firefly luciferin and luciferase are commercially available for measuring the amount of ATP in biological materials.
Fireflies use their flashes to attract mates.
The pattern differs from species to species. In one species, the females sometimes mimic the pattern used by females of another species. The widespread occurrence of luminescence among deep-sea animals reflects the perpetual darkness in which they live. At least one fish has its luminescent organ located at the tip of a protruding stalk and uses it as bait to lure prey within reach of its jaws. When disturbed, one species of squid emits a cloud of luminescent water instead of the ink that its shallow-water relatives use.