To make sure the birds weren't simply drawn to any noise, Yorzinski repeated a similar experiment with captive birds in an outdoor enclosure at Duke University. There, a speaker played two different sounds: peacock copulation calls, or crow caws.
The results matched what she found in the wild. Captive females paid little attention to the speakers when crow caws were playing, but when the love whoops were played, the females moved toward the source of sound and spent more time near the speaker.
"Why they're attracted to these calls and what it tells them these are still open questions," Yorzinski said.
Announcing the fact that he's getting a girl could help a male attract additional mates, she explained.
Studies in other species have shown that females flock towards popular males. "It's like someone's already vouched for him. If he's good enough for one girl, then he might be good enough for another girl, too."
That dating boost could make up for the risks involved in disclosing his whereabouts to potential predators, especially in the birds' native habitat in South Asia where dense trees and grasses make strutting males hard for females to spot.
If distant females are drawn to the love calls made by mating males, what's less clear is what keeps males from boosting their call rate to give the impression that they're more successful than they actually are.
"One of the biggest unanswered questions is why males don't fake it," Yorzinski said. "I've heard males making false calls when there's no mate in sight, so there definitely is some level of cheating going on. Figuring out why they don't do it more often would be the key."
|Contact: Robin Ann Smith|
National Evolutionary Synthesis Center (NESCent)