Fruit Flies: One man's nuisance, another man's treasure

The Drosophila melanogaster is an organism commonly known as the fruit fly. It has received this name because it accumulates near ripened or rotten fruit. It is about 3 mm in length, and belongs to the order Diptera, the order in which most common flies belong to, and the family Drosophilidae. The Drosophila melanogaster may be viewed by many as a common household pest, but the Drosophila melanogaster in biology is so much more than that. It is a model organism, extremely valuable to the field of biological research, particularly genetics.

Drosophila have become extremely valuable to biological research for many reasons. First, Drosophila are economically feasible. It costs very little to purchase and maintain Drosophila allowing many to be purchased for very little cost. Second, they have a short generation time allowing Drosophila reproduction to be rapid, providing biologists with a continuous supply with a very little wait period.
The rapid life cycle of Drosophila consists of four stages: egg, larva, pupa, and adult. The life cycle begins with a fertilized egg that has been laid. After the egg has been laid, it takes about one day for the larva to develop. In the larval stage, there are three periods of molting called instars. These instars occur on days 1, 2, and 4 (first, second, and third instars respectively). In the third instar stage a puparium develops, in which metamorphosis occurs. In the puparium, the larva develops wings and is remodeled into an adult form. The adult form is then hatched from the puparium producing an adult Drosophila. This whole process takes about 14 days, with the life span of an adult consisting of several weeks.

Another reason as to why Drosophila are extremely valuable to biology research is because their entire genome has been sequenced. Their sequence contains four pairs of chromosomes consisting of; autosome 2, autosome 3, autosome 4, and a pair of X/Y chromosomes. The sequenced genome has been established to contain around 165 million base pairs and around 14,000 genes. This sequenced genome has proven to be especially beneficial to the study of human diseases, as around 75% of identified human disease genes correlate with a matching gene in the genome of the fruit fly. The human disease genes correlating to matching genes in the Drosophila have been used as a major research tool for many diseases. Some of these disease include but are not limited to Alzheimer's, Parkinson's, and Huntington's, three common neurodegenerative disorders. Drosophila are also being used to study certain diseases and the mechanisms in which they work such as cancer, immunological diseases, and diabetes. Nonetheless, Drosophila melanogaster prove to be beneficial in many ways to the medical field.

Along with being an ideal genetic organism, Drosophila are extremely easy to work with. The sex of the Drosophila is easy to determine visibly due to the female Drosophila melanogaster being slightly larger than males. Along with differences in size, the male Drosophila can be identified due to a darker part on the back of their body, along with a black patch found on their abdomen. They are also very small in size and require very little room for storage, as well as minimal maintenance.

As you can see, the Drosophila melanogaster may be seen as a nuisance to some, but in science they have provided researchers with valuable information and are an ideal organism used time and time again.

References:
http://www.ceolas.org/fly/intro.html
http://animaldiversity.ummz.umich.edu/site/accounts/information/Drosophila_melanogaster.html
http://www.woodrow.org/teachers/bi/1994/life_cycle.html