Buzz
(Homeland) - Male vinegar flies can prevent females from mating with other males by using a self-made sleeping potion.
A group of researchers from the Bariloche Nuclear Center in Argentina and their colleagues have discovered that male vinegar flies inject a chemical into females during mating that causes them to sleep afterward, preventing them from mating with other males.
In an article published in the journal PLOS Genetics, the team described how they studied the reproduction of vinegar flies in the laboratory using a webcam.
Previous studies have shown that during mating, male vinegar flies inject a peptide into the female's body along with a series of sperm. This action has been proven to make females less attractive to other males.
In this new effort, researchers want to see if there's anything more intriguing about this story from the perspective of male flies.
To understand this phenomenon, researchers raised a group of vinegar flies in the laboratory and then installed cameras to monitor their activities continuously for four days. During observation, the laboratory was illuminated evenly to allow the flies to distinguish between day and night.
From the video evidence, researchers discovered that the only females to wake up and start flying around in the morning, immediately after the lights came on, were the ones that had not mated with male flies. Suspecting that the peptide injected into females during mating was the cause of sleepiness, researchers repeated the experiment. However, this time they intervened to deactivate nerve cells in some females, those cells which reacted to the peptide, before releasing them into the environment to freely mate with males.
The suspicions of the researchers were confirmed when the females with disabled nerve cells woke up just before the lights came on along with the unmated females. Researchers said this indicates that besides affecting the scent of females to potential mates, the peptide also moves to the brain and interacts with sleep-related parts of the brain. This alteration in the biological clock has restricted the females' ability to interact and mate with other males.
Regarding why male vinegar flies inject chemicals into females during mating and alter their sleep cycles, the research team said: 'Male vinegar flies have evolved over time to ensure the survival of their offspring. It's a survival tactic.'
After a while, the influence of the peptide on females diminishes, and they will return to their normal activities along with the entire group.
References: Phys.org, Gigazine
