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Glow Little Glowworm, Glow

Summer 2003 Newsletter

In the evenings of early summer, we are treated to an unrivalled natural light show provided by fireflies — also known as lightning bugs or glowworms. Thousands of these insects can be seen floating silently over meadows and lawns flashing their yellow lights.

Fireflies are members of the beetle family, Lampyridae. These soft-bodied, nocturnal beetles are about ¼ to ½ of an inch long and have brown or black bodies often marked with yellow or orange. In many species, the females are unable to fly.

So how and why the flashing? A chemical reaction known as bioluminescence takes place in the lower abdomen of the firefly, giving off a soft, heatless glow.

Fireflies use this flashing to attract mates. The flying males produce a series of flashes that vary in size and brightness. When a female recognizes an appropriate signal, she flashes back. The male then descends to the female for mating.

Adult fireflies only live for about 5 to 30 days. They feed on nectar or eat nothing. They do not bite, do not carry diseases, and are harmless to humans. So enjoy the summer evening light show!