biologynews.net
Even after they have paired with a male, the female North American barn swallow still comparison-shops for sexual partners. And forget personality; the females judge males by their looks — the reddish color of the males’ breast and belly feathers.
If the male’s red breast is not as dark as other males in the population, the female is more likely to leave him and then secretly copulate with another male, according to a Cornell University study featured on the cover of the journal Science (Sept. 30, 2014).
“The bad news for male swallows is the mating game is never over,” said lead author Rebecca Safran, who conducted the study while a Cornell postdoctoral researcher in ecology and evolutionary biology, and in the Cornell Laboratory of Ornithology. “It is dynamic and continual. This is something that most humans can relate to — think of how much time and money we spend on our looks and status long after we have established stable relationships.”
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