About a month ago Dr. Mrs. Dr. F and I developed fruit fly problem in the kitchen. Working as I do in a mixed research university it seemed natural to walk down the hall and ask some of those overfunded fruit fly experts how they deal with escapees. As it turns out the old saw is actually pretty useful – flies love honey, and vinegar doesn’t help. The solution endorsed by nine out of ten fruit fly geneticists worked well enough that I’ll recommend it here.
You need some tape, a small square of stout paper (try a business card), honey and a small flask-type container with a narrow mouth. Researchers use erlenmeyer flasks, I used one a one-serving cognac bottle.
Roll the stout paper into a cone, leaving a hole in the bottom just big enough for two fruit flies to crawl through back-to-back (if you don’t know how big that is, you don’t need a honey trap). Cover the bottom of the bottle/flask with honey, then add an equal measure of red wine and mix. Push the paper cone into the flask pointy end first and tape it in place. That’s it! You’re done. Flies will chase the honey/wine smell like guys after football and beer, but the geometry of the inverted cone makes it nearly impossible to find a way out.
Another tip from my geneticist friends: if your can’t figure out whether related mutations act through the same pathway, try epistasis! No need to thank me.
Per the comments, it appears that you can catch about the same number of flies with vinegar. Add that to my earlier look at the boiling frog parable and this blog has become something of a graveyard for folk biology.
Use the thread to list any other scientifically bogus folk sayings that come to mind.