Outside is the summer night is getting dark. What are those twinkles in the yard? They are fireflies. They signal to one another with their lights. The males fly round. The females wait on the grass or a plant and watch for a male's twinkling light. If she likes him, she will twinkle once. They flash at one another about twenty minutes, not all night. Some kinds flash for hours.

Fireflies are not flies. They are beetles with three main body parts: a head, a thorax, and an abdomen.

Its head has two large eyes. The eyes have many flat surfaces. The scientists believe these make the firefly see objects like looking through a cracked mirror. On its head are two antennas. These are used to touch and smell and to check out its surroundings. The head also has two sharp jaws called mandibles that it uses to catch its food.

The firefly has no teeth. It uses maxillas to chew its food. These are found behind the mandibles.

The thorax comes behind the head. The firefly's six legs are attached to the thorax. Each leg includes a foot with two claws. These serve the beetle in climbing.

The firefly's two sets of wings are attached to the thorax. The front pair is stiff and protects the lightweight wings underneath. When the firefly wants to take off, it opens its front wings and uses the other wings to fly like a ladybug does.

The abdomen is behind the thorax. Its light organs lie on the bottom of the thorax. These make the firefly glow yellow or yellow-green.

The light organs contain chemicals to mix and make light energy. The firefly's light is called bioluminescence (by-oh-loo-muh-NEH-sunts).

A firefly hatches from an egg. The mother firefly lays from 40 to 1,000 eggs at one time during the summer! She places them in loose, damp soil to keep them safe from the sun's light and heat.

The round, tiny, smooth egg glows! But it doesn't twinkle. The egg hatches in less than a month.

Then the firefly is called a larva (LAR-va). It resembles a worm with ridges. In the day the larva hides and sleeps and hunts for food at night. It eats earthworms and soft insects. It's like a human baby and must eat liquids. The larva grabs the insect by its mandibles. Then it squirts a liquid into the insect through its mandibles to soften the insect into a thick liquid. This is the larva's meal.

Soon the larva grows too big for its skin and molts. To molt, the larva splits its skin open and wiggles out and then grows a new skin. The larva molts several times through the winter. Some larvas of firefly species are adults in the spring; other kinds take another summer and winter to become an adult.

The firefly larva builds a shelter out of mud. The larva chews the soil into mud and then spits out the mud in strips. Over and over, the larva piles the mud strips atop each other to make its shelter. The larva crawls in and curls up in its new home. There it stays for about five weeks. Once more it molts. This time it forms a stiff, white cover and is called a pupa (PYOO-puh). The pupa grows its firefly organs for about ten days. Then it is an adult firefly.

©2008 Carol Hegberg. Carol Hegberg writes articles for children's magazines. She also is an online professional freelance editor and can be reached at http://editing-writing.com/bios/carol-hegberg/index.shtml