Why Fruit Flies?

Even though fruit flies, classified under the family Drosophilidae, have been used in genetic research on heredity for centuries, people often wonder, why fruit flies? Why do scientists prefer fruit flies to famous lab animals like white mice in the study of genetics? We now provide some answers.


1. Its Size


As everyone knows, fruit flies are small: in fact, they are only 3mm in size, and thus, easy to grow and keep in small containers in laboratories, reducing the hassle of working with big and cumbersome lab animals. Being small and helpless, scientists can manipulate them easily, for example, in anesthetizing and sexing them (refer to bottom post for definition of "sexing").



2. Easy to raise


How difficult can it be? Fruit flies are hardy and resilient to changes in environmental conditions, and only need a miniumum amount of food to survive. And, they feed on almost anything.



3. Short life cycle


Fruit flies only have a full life cycle of about a month. Thus, breeding experiments carried out on flies can garner results in the shortest possible time, since scientists do not like to waste time. The study of various continuous generations of fruit flies can be undertaken in only a matter of a few months. Fruit flies are fertile throughout the year and extremely prolific, producing a new generation every 12 days, or 30 generations in a year! Since they reproduce so rapidly, and in such great amounts, many breeding experiments can be carried out at once, thus there will be greater chances of successful experimens and breakthroughs. Compare all that to breeding chimpanzees. One generation can take decades to develop.






Life cycle of the fruit fly. Taken from http://www.anatomy.unimelb.edu.au/



4. Easily distinguishable


The males can be easily distinguishable from their female counterparts by observing their physical features, making it easy for seperate breeding experiments to be carried out.



5. Embryonic development


The eggs of the fruit flies develop outside the body, thus it is easy to study the effects of mutations on their development.




Can you see the fruit fly eggs? Taken from http://upload.wikimedia.org/wikipedia/en/thumb/c/c4/Drosophila_eggs_Nuuanu.jpg/200px-Drosophila_eggs_Nuuanu.jpg



6. Simple


Fruit flies only have 4 chromosomes, making it easy to study the different effects of different genes on their development. Morever, all the genes, and their functions, had already been identified and stored in databases worldwide, making the information easy to access to be used by scientists.






Fruit fly chromosomes. Taken from http://www.news.bbc.co.uk/



Thomas Hunt Morgan and his beloved flies


Morgan was one of the most famous geneticists who worked extensively with fruit flies. He started working seriously with Drosophila in 1907, with the intention of breeding many generations of flies, and perhaps getting one that is different from the others. He hoped to find one that was mutated. After wasting two years of work, he failed to detect a single mutation. However, he did not give up even after that, and continued with his interest, passion, and devotion to the study of fruit fly genetics.

Most of this information is taken from http://www.columbia.edu/cu/alumni/Magazine/Legacies/Morgan/