You can’t ask a fly whether she finds intercourse rewarding. But a new study published on Monday, 6th May 2019, in the journal Neuron has shown that the sensation of copulating — and not just insemination — is responsible for female fruit flies temporarily losing interest in other love partners.
The findings bring scientists a step closer to answering important evolutionary questions about the role of female pleasure in the reproduction process.
Ulrike Heberlein, a senior fellow at the Howard Hughes Medical Institute in Virginia, and Lisha Shao at York University in Toronto set out to investigate the neurons involved in the reward circuitry of Drosophila melanogaster (or the common fruit fly).
They ended up finding, however, a pair of sensory neurons in the abdomen that were “female-specific”. They “likely transmit excitatory signals from abdominal sensory systems to the brain.”
Biologists have long known that proteins in a male fly’s ejaculate make females lose interest in other partners for up to a week. This is a trick males use to ensure their own sperm fertilises.
So the researchers set up an experiment pairing the female fruit flies with males that could not ejaculate.
After mating, the females lost interest in other males, even though they had not received any sperm. By contrast, when they blocked the neurons perceived as rewarding, the females kept trying to mate.
The cells, therefore, appear to control the mechanism by which females determine they’ve copulated, independent of the so-called “sperm effect.”
Speaking to AFP, Heberlein said,
“The question of whether a successful mating has happened is very important in evolution. Females need to be able to tell whether they copulated successfully or not. Else it makes a lot of sense to try to mate again.
Past research has found that male flies find mating rewarding when they ejaculate.
Heberlein said that they suspect that the reward-giving neurons they had found in the females’ abdomens were linked to intercourse. Nevertheless, they require more work to definitively confirm that intercourse was pleasurable.
(This story is auto-generated from a syndicated feed.)
Also read: Science Reveals Any Amount Of Drinking Is Bad For You