Although flies are known for being attracted to sweet things, they actually prefer beer over sugar water — even beer that has a relatively low sugar content, such as pale ale. This is because they are more attracted to a molecule called glycerol that is produced by yeast as beer ferments. Besides beer, glycerol is found in a wide variety of things, including cosmetics, some medications and antifreeze.
More facts about flies and glycerol:
- Researchers hope to use the information they find out about how flies recognize compounds such as glycerol to understand more about how taste works in humans. Having a better understanding of how flies chemically experience the world also can help with the development of pesticides.
- Houseflies' mouths absorb food like a sponge, so they soak up the food first and then suction it into their bodies. They can eat dry food by either spitting or throwing up on it until their mouth can soak it up.
- Flies like to eat rotten or decaying food because it's generally more liquified. It also usually smells stronger, so it's easier to find.
