Does Alcohol Kill Flies on Contact?
WouterAlcohol has been used as a sanitation agent for thousands of years. Many ancient civilizations drank it to disinfect surfaces, but flies and other insects are resistant to it. In fact, scientists have discovered that fruit flies actually prefer the 4% alcohol concentration, about the same as a bottle of beer. In addition, fruit flies often have parasitic wasps, and these wasps can be killed by alcohol.
To find out if alcohol kills flies on contact, scientists have to look into the way fruit flies react to the compound. Flies can become excited and animated when exposed to alcohol vapors. In fact, this chemical can even prevent flies from getting blood-borne parasites.
The reaction between flies and alcohol may involve several odors. Flies may respond to alcohol by smelling an odor that’s similar to food, or to a series of different food odors. One example of this response is the smell of ethyl acetate. Flies that experience this reaction are less likely to lay eggs or to survive.
The behavioral immune response continued even after the wasps were removed. The adults of these flies still preferred the alcohol-soaked food source for several days, even when the food source was soaked with up to 16 percent alcohol. The researchers found a protein called neuropeptide F that controls this response. Other fruit fly species are likely to exhibit a similar response. Researchers provided different sources of food to the larvae to study the behavior. They observed the behavior of the fruit flies with and without parasitic wasps.
