FIREFLIES

Far more than a delight for summer nights, fireflies promise medical breakthroughs.

FIREFLIES. Fireflies glow to communicate with potential mates as well as predators. When attracting a mate, it all comes down to the twinkle. Every species of firefly has its own distinct pattern of flashing their light-producing bottoms. Males and females of the same species will flash this pattern to notify each other of their presence.

Fireflies also glow to warn predators to stay away. Most species of fireflies are filled with a nasty tasting chemical. Predators who have had a mouthful of this chemical quickly learn to associate the firefly’s glow with a very bad taste.

Most scientists and researchers believe that development and light pollution are driving fireflies away. Most species of fireflies are born and thrive in the rotting wood and understory of forests near lakes and ponds. As they grow, they tend to stay near where they are born. As more forests and open fields are developed, their habitat becomes threatened.

Light pollution—the excessive use of artificial light—may also be driving firefly populations down. Fireflies use their bioluminescence to attract mates. If too much light surrounds their habitat, there is a chance that males and females won’t find each other to mate. Less mating means fewer fireflies, which means fewer chances for Hoosiers to enjoy chasing fireflies on a warm, summer evening. (1)

During the summer of 1984, the Sigma Chemical Company of St. Louis sponsored the Sigma Firefly Scientists' Club in Dubuque. The family of Pat Francois collected a record for the year of 8,200 fireflies that earned them $82.00. Sigma paid one cent each for the insects with an additional ten-dollar bonus for every twenty-five thousand.

In 1986 scientists explained that they had used gene splicing techniques developed in the 1970s to introduce the gene that carries tje instructions to make the enzyme luciferase--the firefly;s 'lantern'--into a tobacco plane. From the individual tobacco cells containing the luciferase gene, scientists grew entire plants carrying the gene. The plants produced light when their luciferase, produced by the transplanted firefly gene, was combined with adenosine triphosphate and oxygen, which are in the plant, and an organic molecule called luciferin which is added. The implication of the study could lead plant breeders to obtain important information on how to help a plant increase its resistance to disease by linking the firefly gene to the gene for disease resistance and tracking it through several generations. (2)

Unable to grow fireflies in captivity, companies like Sigma wanted the chemicals that give the insects their magic glow. Using compounds made from fireflies, doctors were able to diagnose congenital gaiactosemia in babies at birth. This condition imitates death by suffocation. Alerted parents can eliminate gaiactose from the baby's formula.

Extracts from the firefly light can also be used to diagnose the possibility of some forms of mental retardation and search for the causes of cancer, muscular dystrophy and heart trouble. Luciferin and luciferase, chemicals found in firefly light, have even been used to manufacture a shark repellent.

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Source:

1. "Fireflies," The Nature Conservancy, https://www.nature.org/en-us/about-us/where-we-work/united-states/indiana/stories-in-indiana/fireflies/

2. "Genetic Engineering Feat Produces Tobacco Leaf That Glows in the Dark," Telegraph Herald, November 7, 1986, p. 2