Up until about the 18th century, people believed in a phenomenon called spontaneous generation. The idea of spontaneous generation was that all kinds of creatures, including mice and various insects such as fruit flies, were spontaneously spawned from inorganic matter. Dirty underwear, rotting meat, and other foul materials where thought to mysteriously produce these animals.

When it comes to fruit flies in our homes, the idea of spontaneous generation seems to be in play. Fruit flies seem to magically appear around fruit and other foods quickly and without fail in an otherwise insect-free kitchen. Of course, modern science has proven that spontaneous generation is impossible, so the question remains; where do fruit flies come from?

Fruit flies are tiny winged insects that boast a meager length of 0.2 inches (3mm). They are brownish in color, with striped bodies and relatively large red eyes. They are perfectly adept in smelling food from great distances. With their great sense of smell and tiny bodies, fruit flies can maneuver into your kitchen through window screens, door jams, or any other crack in your home. Occasionally, they may catch a ride in your grocery bags or hatch from eggs laid in less than fresh food brought home from a grocery store.

A congregation of fruit flies can become a nuisance. Fruit flies feed on alcohol, which is produced when fruits and vegetables begin to ferment. The alcohol in wine, beer, and other alcoholic beverages is also appealing to fruit flies. Fruit flies not only feed on these foods, but also lay eggs in them that hatch into larvae in a matter of hours. In almost the blink of an eye, fruit flies can infest any kitchen.

Removing the food source is the first step to eliminating fruit flies. Some non-food items, such as wet mops, dirty dishes, and old sponges, are able to support fruit flies, so be sure to clear these from your home as well. The remaining fruit flies can easily be trapped by constructing a paper funnel and placing it in a jar or bottle containing a small amount of wine, beer, or decaying fruit. The fruit flies will enter the funnel to reach their feast and will not be able to find their way out.

Although fruit flies are a pesky nuisance to most people, these tiny insects have made a gigantic name for themselves in the field of science. Fruit flies, or Drosophilae, have been invaluable to the field of genetics. The short, ten-day life cycle of the fruit fly, its avid ability to reproduce, and its large chromosomes make the insect an ideal specimen for laboratory experiments in heredity.

Fruit flies have also been a source of fuel for the creation vs. evolution debate. Creationists, who oppose the generally accepted theory of evolution, claim that the use of fruit flies in the laboratory, specifically the attempt to create new species of fruit flies through the mutation of chromosomes, has yielded no surviving results. Evolutionists rebuke the claim with the fact that fruit flies have too few chromosomes to provide an evolutionary advantage when manipulated. Basically, evolutionists hold that fruit flies are successful just as they are and have no reason to change.