Furthermore, the females had gone through genetic changes even before they mated that were expected to occur after mating. Sperm contains proteins that are supposed to trigger a number of changes in the female, including ovulation and the preparation of areas to store the sperm. The males, according to the study, had "negligible effect" on the genetic changes in the females.
The study concludes that the females were "poised" for reproduction even before they were turned over to the males.
There's one other thing that isn't clear. The scientists admit they aren't real sure exactly what happened in the "mating chamber."
It's "not possible to distinguish" whether the females really made the decision to yield to the male members of the desired strain, or whether the lucky males were more aggressive than the males in the other strain, they said.
Whatever, the geneticists are pretty sure they captured genes at work.
"Our research helps to shed light on the complex biochemistry (genetics) involved in mate selection and reproduction," said Mariana Wolfner, professor of developmental biology at Cornell and senior scientists on the project.
She added that the research may help scientists develop ways to control unwanted insect populations by activating or deactivating genes "that play a role in female mating decisions."
The fruit fly findings probably apply to other animals as well, but to humans? That's a "long stretch," McGraw said.
A human life is much more complex than that of a fruit fly, and even if fruit flies are unthinking robots when it comes to picking a mate, humans probably have more control over the process.
That doesn't necessarily mean we always get it right, of course.