The Cold Light
of the Firefly
In tropical and temperate regions, the firefly
is recognized by the flashing light it uses to attract a mate. Interestingly,
the firefly’s light is superior to the incandescent and fluorescent light
produced by man.
An incandescent light bulb emits only 10% of
its energy as light; the rest is basically wasted, discharged as heat. A
fluorescent bulb performs much better, emitting 90% of its energy as light. But
neither of these is a match for the firefly. With very few ultraviolet
or infrared rays, the light emitted by this insect is nearly 100 percent
energy efficient!
The
firefly’s secret lies in the chemical reactions of the substance luciferin {(4S)-2-(6-hydroxy-1,3-benzothiazol-2-yl)-4,5-dihydrothiazole-4-carboxylic
acid}, the enzyme luciferase, and oxygen. Special
cells called photocytes use luciferase to trigger this process, with oxygen as
fuel. The result is cold light—so named because it produces virtually no heat.
LIGHT EFFICIENCY
10% 90% 96%
Incandescent
bulb Fluorescent bulb Firefly
No comments:
Post a Comment