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This is Scientific American 60-second Science. I'm Jason Goldman.

One of the most impressive scenes in the world of birds is a peacock displaying its impressive, iridescent¹ feathers, technically² known as its train. While the female peahen l???ooks on, the peacock spreads his train out and ruffles³ it back and forth⁴ as the sun highlights the red, blue, and green within the feathers.

(Train rattling⁵ sound)

But these iconic trains are only half of the story of how the boys impress the ladies. Both male and female peafowl sport crests⁷ on their heads, small feathers that stick straight up, like a Mohawk.

"The crest⁶ feathers that actually give the peacocks' their Latin name, they're called Pavo cristatus, the crested⁸ pheasant. And so I was intrigued⁹ by the fact that people didn't really know what the function of these crests were."

Haverford College physicist¹⁰ Suzanne Kane.

A biologist might see those feathers and assume they are visual signals, but as a physicist, Kane had a different idea.

"We were curious in my laboratory about whether the preferred vibrational¹² properties of the crest feathers might, by any chance, agree with the preferred vibrational properties of this train-rattling display that the males do."

So the Kane and her colleagues exposed crest feathers from preserved, dead peafowls to simulated displays of male and female social behaviors, like wing-shaking and train-rattling.

"And so we were just gobsmacked to find out that they did agree."

What all that means is that the peafowls' head crests are specifically tuned¹³ to the vibrations¹⁴ produced by the train-rattling of its own species. The crests thus act like a sort of special antenna¹⁵ meant to pick up a single kind of sound. The findings are in the journal PLOS ONE.

The researchers also point out that there are at least 35 other types of birds, distributed across ten taxonomic orders, that have both head crests and displays with a vibration¹¹ component¹⁶.

"A lot of those kind of tactile¹⁷ aspects of displays are really not even very well described."

University of British Colombia zoologist¹⁸ Roz Dakin, who worked with Kane on this study.

"There are species that dance and vibrate on perches²⁰, and you know, the female's sharing the same perch¹⁹ as the male, and feeling what's going on through parts of her body like her feet. There are species where birds rub feathers on each other... What we're suggesting here is that a sensory²¹ function of feathers in social displays may be more widespread than we appreciate right now."

Seems that the females really do feel something about a particular peacock.

Thanks for listening for Scientific American — 60-Second Science. I'm Jason Goldman.