Maintenance of Fly Stocks

Theoretical Considerations

Generally flies are flipped into a new vial every generation. The larvae placed into the old vial will repopulate the new vial. Keep one old vial and one new vial banded together. A fly generation is 10 days. To see if new larvae are being born, look for tiny black specks in the media after about 10 days. If need be use the microscope to look. Since generations are too fast, there is no reason to keep track of generations. Try to flip >20 (10 M, 10F) flies into a new vial to avoid genetic drift. No need to separate homozygotes from heterozygotes.

Food

• Buying food already in tubes costs $20 for 100 tubes.

Flipping Flies

1. Grab a new vial and take out the cotton ball
2. Gently tap the older vial on the counter (on a mousepad) to drop all the flies down to the media
3. Take out the old vial's cotton ball then flip the new vial on top of it, inverted
4. Flip both vials and tap on the surface to move flies to the new vial.

If you dont get all the flies into the new vial its ok, but you should get >20 flies into the new one.

Expanding Colonies

1. Grab a conical flask.
2. Flip about 40F and 10-40M flies into the conical.