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FIREFLIES BRIGHTEN NIGHTS WITH EFFICIENT LIGHT

It was a warm summer evening when Fred Hall and his family came by for a visit at Timber Trails.

"I'll be darned, the Bigelows have fireflies!" exclaimed the museum director, as he stepped from his station wagon at the top of the driveway.

We had become so accustomed to those many bright flickerings of light over our Eden lawn that it had never occurred to me that people seldom see fireflies in Hamburg, scarcely eight miles to the north. Furthermore, I could not recall having fireflies around our home when we lived in Williamsville.

It certainly does seem strange that just a few miles apparently make so much difference in whether these wonderful insects of the countryside flourish. Possibly, the clover in the neighboring hay fields attracts the fireflies, although I am inclined to suppose that nature has simply consigned these insects to the fauna of the Carolinian Life Zone -- just as mockingbirds and red-bellied woodpeckers show a distinct preference for the lowlands of the Ontario Plain.

Most recently, I watched the pulsating flashes (2.1 second intervals) of the male fireflies, and marveled that they were so often in unison. They reminded me of the countless whippoorwills and a chorus of bullfrogs that shared the darkness of Indiana while fireflies danced in the meadow.

As a youngster, I once chased them across a nearby golf links, managing to bottle up enough blinking luminescence to serve as a primitive flashlight -- equal to five watts at least.

These friendly torchbearers are actually a type of beetle, with soft yellow and black elytra covering their wings and abdomens. Our native firefly (Pyractomena borealis) is just one of 50 species found in the United States, with many spectacular relatives in the tropics of South America.

The intermittent glow of their cold, greenish light is transmitted by special organs located in the sixth and seventh abdominal segments. Here, masses of cells yield substances known as "luciferin" and "luciferase," the latter serving as an organic catalyst. Controlled by the insect's nervous system, oxygen passes through the trachea, combining with the miraculous luciferin to form oxyluciferin, the chemical compound that generates 98 percent efficient light in the presence of luciferase.

Unlike most other insects, which secrete pheromones in order to find each other in the dark, our fireflies use these remarkable inboard lanterns to signal a mate -- males with more sudden bursts of light than the responding female's steady glow.

Very few people associate these familiar adult insects with the luminous larvae, the "glowworms" occasionally found hidden in a patch of weeds. Those odd-looking, predaceous grubs are never garden pests. In fact, they have a rather ravenous appetite for all those horrible slugs that seem to upset my friends and neighbors.

When the little glowworm prepares to devour a slug, first it uses its hollow mouthparts to inject its victim with a dark secretion that rapidly liquefies and partially digests it so that it may then be engorged.

In some species, even the eggs of a firefly may glow from the luminescence of the unhatched larvae within. Frogs that gorge themselves on fireflies also have been known to shine in the dark, revealing contents of their stomachs -- like having dinner by candlelight.

A few summers ago, a group of us were stranded by a roadside in the Dominican Republic after our bus had broken down. What might have been a long and dreary wait immediately was brightened by one of the greatest spectacles of a tropic night: a pulsating sea of fireflies all flashing together over an irrigated field of pineapples.

Soon these entomologists had assembled their nets and collected an assortment of luminous insects, including large click beetles having the appearance of sleek sports cars with two yellow headlights and one red taillight, which remained "switched out." The beauty of that magic night will never be forgotten -- nor will the hordes of mosquitoes.

Scientists already have spent years probing the secrets in the chemistry of fireflies, hoping to discover some way to produce a synthetic luciferin and luciferase, the breakthrough that promises to revolutionize lighting. Man has never been able to produce light so efficiently and so devoid of heat to equal the perfected source in the body of this lowly insect, our common firefly.

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