Summer evening light-bearers
Tuesday, June 01, 2010
Media contact: Jessica Basham
Humidity hangs thick in the night air. The
sun has disappeared from the horizon, but the evening is still
warm. Suddenly there is a tiny twinkle - a gentle glow that
flashes on and off every few seconds. A firefly!
A firefly's glow and flashing is how this member of
the beetle family mates, defends itself and communicates it is in
trouble. These small insects live in marshes or wet, wooded
areas and open fields by water. Many of the firefly's food sources
live near water. Would you believe a firefly can eat snails?
Fireflies also enjoy munching on slugs, caterpillars and other soft
insects. Nectar is another food they enjoy.
How does the firefly produce its flickering light
in the night sky, and why does it flash?
The light produced by fireflies is a chemical
reaction in its abdomen. The cells it carries to make light are
called photocytes. These cells contain two chemicals:
luciferin and luciferase. When fireflies breathe in oxygen, the
chemicals create the light we see, which is why its family
scientific name, Lampyridae, meaning "torch bearer," is so
To attract a mate, male fireflies flash a series of
lights. The female sits low to the ground on a leaf or
branch. If she likes what she sees, she signals back. This
can be a dangerous game of love. Certain female fireflies
imitate blinks of other, smaller species and will lure a male of
that species so she can eat him. The firefly also can become
a meal when it flashes distress signals.
But the firefly's flashes also may protect
it. The yellow light it produces warns predators that it
doesn't taste good. The chemicals that make the firefly glow
are bitter to birds and insects that are looking for a meal.
Adult fireflies live only long enough to mate and
lay eggs. The larvae usually live for a year before becoming
adults. Firefly larvae also glow, which is why people call
them glowworms. There also are other beetles known as
Fireflies are important to scientific
discoveries. One of the neatest things a firefly has helped
scientists invent is the glow stick. Also, scientists reproduced
the glowing chemical it creates to help with many medical
procedures. The chemical helps scientists detect harmful
bacteria in blood or urine and milk, juices and other foods.
Join the Get Outdoors Florida! movement and the
Museum of Science in Boston to track fireflies. Scientists
want to learn as much as they can about these insects. So,
while you are outside looking for nature's flashing beetles, you
can help researchers learn where fireflies live and information
about their activity during the summer. Visit www.mos.org/fireflywatch to learn more about
the program and how to participate.