The glowing fireflies or glow-worms have always fascinated man. They present a wonderful sight at night. Scientists have been trying to find out form the very beginning how and why fireflies emit light.
A chemical substance called luciferin present in the abdomen of a glow-worm combines with oxygen
The firefly is, in fact, a flying worm. Both the male and the female of this worm have wings. In some species, however, females are without wings and are known as glow-worms. They are blackish and their bodies are very soft. They mainly live on the nectar of the flowers. They are found in large number in the tropical humid areas. They emit light in flashes.
The light producing organ is located in the bottom of the abdomen in the rear side and controlled by nerves. It contains two chemicals named luciferin and luciferase. Luciferin combines with oxygen to produce light. Luciferase acts as a catalyst for this reaction. It is interesting to note that the light emitted by them produces on heat. Such as process of production of light is called bio-luminescence. Luciferin is the active luminescent material in the fireflies. The firefly can control the length and rhythm of the flashes from the abdomen.
Fireflies usually emit yellow orange light. Today scientists can produce such lights in their laboratories. But that can only be done by extracting lucieferin and luciferase from the fireflies. Fireflies are usually 4 to 11 millimeters in length.
Now one may wonder why a firefly produces light. The first reason is that both the male and female fireflies emit light to attract each other. The second reason may be that the light so produced may frighten birds and prevent for this, these fireflies produce a spectacular sight.