I have my fruit flies

1. I have my fruit flies Now what do I do???!!!

2. How was my vial set up? • Flies were ordered from the supply company • Specific crosses were ordered, so the supply company selected virgin females and added males which had the desired traits. These parents were the P1 generation. They were removed before the culture was shipped. We received the F1 generation. In the simplest sense these were all hybrid. • F1 flies were put into new vials with food (the blue or white stuff) and allowed to mate. These were the adults you may have had in your vial.

3. What do I do first? • The F1 generation must be removed from your culture after you know larvae are developing. • Why? You don’t want the F1 generation interbreeding with the F2. The F2 is the generation you want to tally.

4. How do I remove the F1? • There are three ways to remove flies. • Fly Nap • Alka-seltzer • Chilling • Fly Nap is fast, but smelly, and only available at school. • The Alka-seltzer method requires a small container (like the fruit fly vials) with a lid (for vials, a one holed rubber stopper size 6 ½), and a piece of tubing or plastic pipette through the lid or hole of stopper. Add ½ Alka-seltzer to ½” of water, cap. Immediately insert tubing or pipette tip into vial of flies to be immobilized. Hold the fly vial upside down. Carbon dioxide will displace O2 briefly knocking out the flies. This will only last a minute or two. Remove flies and place in closed container in freezer for a few minutes then count on ice in closed petri dish. If they start moving return to freezer for as long as needed. • Chilling in the freezer is effective but risky if you don’t separate the adults to be counted first. Many a student has lost their flies to too long in the freezer! Alka-seltzer Flies

5. When do I begin to count? • Watch your culture. The presence of dark pupa indicates new adults soon. • Begin counting as soon as you have adults. This is day one. • Count for seven calendar days. Longer counting runs the risk of mixing generations. • You may miss a day but be aware there will be more to count when it is time. Seven full days of hatching should be counted.

6. Where and when do I count? • You may take your culture home and count or you may count at school. • At school you may count in the mornings before school and 1st,4th,5th, and 8th blocks. There will be no counting at lunch or after school. Bring them home if the above times don’t work for you. • At home you will need a magnifying glass. You may buy these somewhere like Walgreen’s. At school I have dissecting scopes and magnifying glasses. • At school you may use the fly nap or Alka-seltzer method for immobilizing your flies. At home you should use Alza-seltzer and chilling. You should not chill too long as some traits can become hard to see. • Do not release flies into the wild. They should be placed in a vial of oil or rubbing alcohol for disposal. A film canister works well for this.

7. How to tally • Make a data collection sheet for the following information. The data must be kept together for each fly • Fly number • Date Counted • Sex • Eye color (white, wild, or sepia) • Wing length (apterous, vestigial or wild) • Body color (wild is grey, black is called ebony)