Bred invertebrate myself,
Rescue / shelter organization
Posted Jun 24, 2013
I have been studying fruit fly genetics for my entire career as a researcher. Most people consider the fruit fly a pest, but they are actually quite interesting and fun to watch for those who have learned the art of insect husbandry.
They are very quiet creatures, and they hardly make any noises even when flying by your ears. They can easily survive outside a container in a household with fruit lying around, but this can become a problem since they are able to reproduce rapidly. It is best to keep these flies inside a plastic or glass container with a cotton plug (or other breathable screen). They can be fed a media you can make at home using vinegar, sugar, potato flakes, and yeast. Make sure the food isn't too wet or too dry. If the food is too wet the flies will get stuck in their food, and if the food is too dry, the larvae they lay will die before pupating.
Fruit flies take ~10 days to reach maturity once they are laid. This process is divided up into several stages and is very interesting. The egg first develops inside the mother as egg chambers. During the last stages of egg chamber development the sperm, which is stored in the spermathecae, is added to the egg and the cells supporting the development of the egg die while forming the eggshell and delivering the last of their nutrients to the egg. Once the sperm fertilizes the egg, development begins. Gastrulation then occurs ~3 hours later. These embryos develop into larvae, which molt several times giving rise to 3 distinct types of larvae, each bigger than the last. After around 7 days, the larvae leave the food they have been living in and feeding off of and begin wandering for a place to become pupae. This is the stage when the metamorphosis from larva to fly occurs. You can see them develop inside of of a protective semi-translucent cocoon. Once they finish developing, they will eclose (hatch) out of their cocoons and start looking for a mate after a few hours. Because of the rapid life cycle of fruit flies, it is best to change their bottles every 2-3 weeks. A bottle can sustain flies for several more weeks, but it is not advised since the flies will become less healthy and without preservatives, the food will become moldy. The development time of fruit flies can be altered by temperature, so this process can become a few days faster or slower depending on the conditions they are living in.
There are many different strains of fruit flies available online. The fruit fly genome can be studied in great detail on www.flybase.org
Over 3/4 of the genes have mutants available, and www.flybase.org will provide the links to the stock center that will be able to provide that strain to you. Most mutant strains, as well as a huge number of transgeneic flies are available at flystocks.bio.indiana.edu.
The development of many of these mutants is very interesting, and the combination of mutations and transgenics can provide enough new information to maintain thousands careers in biological research.