Flies that can’t find love turn to booze for their buzz: Study

Male fruit flies enjoy sex, so what happens when they can’t get it? They drink.

This is according to new research published in the journal Current Biology.

In a bid to better understand the brain's reward pathways, scientists from Bar-Ilan University in Israel made a few minor tweaks of a fruit fly's genes to make them ejaculate inside an actual red light district.

"Successful mating is naturally rewarding to male flies. Male flies that are sexually deprived have increased motivation to consume alcohol as an alternative reward," senior researcher Galit Shohat-Ophir said.

The researchers coupled a nerve in the abdomen to a type of light-detecting receptor. Evidence had shown that this particular neuron could be 'switched on' by exposure to red light, triggering ejaculation.

They then placed the flies in a box that emitted a red light and tracked the flies' movements. The flies, they discovered, showed a strong preference for the red light. When offered food laced with ethanol, the satisfied flies turned it down in favour of a plain sugar meal. 'Unsatisfied' flies happily lapped up the tainted brew.

"The principles by which the brain processes reward are extremely conserved in all animals; this is a really basic every day machinery that helps animals survive," Shohat-Ophir said.

"Drugs of abuse use the same systems in the brain that are used to process natural rewards. This allows us to use simple model organisms to study aspects of drug addiction, including the interplay between natural and drug rewards and the connection between experience and the mechanisms that underlie the risk to develop drug addiction."