Science Buddies: "Ask an Expert"

Hello, my name is Nicole and I am seeking advice for the science fair experiment I will be doing this year. For my experiment, I will be testing the effects of genetically modified food on fruit flies. I will test organic food on a control group. I plan on measuring their life spans and fertility. What I need help with is:
A. How to create a fruit-based media for the flies to eat.
B. The number of flies and type I should use in my experiment. I would also need to have a detailed overview of their lifespan in order to design my experiment. For example, I would need to know how long it takes for the flies to sexually mature, lay eggs, and how long it takes for those eggs to hatch. As I have been researching online, I have been getting mixed answers Also, I would need to know how many eggs they typically lay and the conditions I should keep the fruit flies at (temperature, etc),

Hi, Nicole!

I spent a lot of time around fruit flies when I was in college, but never had to prepare media for them. This subject has come up before, and a recipe with links can be found here: https://www.sciencebuddies.org/science- ... hp?t=12984

If you do a google search on "drosophila life cyle" you should find the information you need on their lifespan. When we taught on drosophila, we'd give the flies a week to lay eggs, a week for them to hatch into larva, a week for them to pupate, and then a week until we had adult flies (so about 4 weeks total). You can find a graphic here: http://whatcom.wsu.edu/ipm/swd/slides.html. We just kept them at room temperature, if I remember correctly. This looks to be a good resource on raising drosophila (fruit flies) in laboratory conditions: http://insected.arizona.edu/enforcers/r ... trear.html

Good luck!

-Lisa

Hello,
I hope your project is going well so far. I just finished working with Drosophila in grad school and much of what the above post said is correct.
We made media using potato meal and yeast pellets. The flies were kept at 37 degrees for an increased growth rate (though they still grow and reproduce at 25 degrees). 7 hrs is typically the length of time it takes for flies to be sexually mature about being born.
What variables do you plan on looking at in terms of the effects of GMOs?