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, iridescent feathers, technically known as its train. While the female peahen looks on, the peacock spreads his train out and ruffles it back and forth as the sun highlights the red, blue, and green within the feathers.
(Train rattling sound)
But these iconic trains are only half of the story of how the boys impress the ladies. Both male and female peafowl sport crests on their heads, small feathers that stick straight up, like a Mohawk.
"The crest feathers that actually give the peacocks' their Latin name, they're called Pavo cristatus, the crested pheasant. And so I was intrigued by the fact that people didn't really know what the function of these crests were."
Haverford College physicist 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 vibrational 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 tuned to the vibrations produced by the train-rattling of its own species. The crests thus act like a sort of special antenna 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 vibration component.
"A lot of those kind of tactile aspects of displays are really not even very well described."
University of British Colombia zoologist Roz Dakin, who worked with Kane on this study.
"There are species that dance and vibrate on perches, and you know, the female's sharing the same perch 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 sensory 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.
這裡是科學美國人——60秒科學。
我是傑森·古德曼。
鳥類世界最令人印象深刻的場景之一，就是孔雀展示它那引人注目的彩虹色羽毛，術語稱之為尾屏。
當雌孔雀在一旁觀看時，雄孔雀便會展開尾屏並令其來回舞動，太陽會令其羽毛內的紅藍綠三色更加閃亮。
（孔雀開屏發出的沙沙聲）
但標誌性尾屏只是雄孔雀打動雌孔雀的一半原因。
雄孔雀和雌孔雀都會炫耀頭上的羽冠，即直立的小羽毛，就像莫霍克髮型一樣。
孔雀的拉丁語名字Pavo cristatus就因其羽冠而得名，意為有羽冠的野雞。
人們並不知道這些羽冠的功能，這一點引起了我的興趣。
哈弗福德學院的物理學家蘇珊·凱恩說到。
生物學家可能會注意到這些羽毛並假設其為視覺信號，但作為一名物理學家，凱恩有不同看法。
在我的實驗室裡，我們好奇的是：
冠毛偏愛的振動特性是否有可能與雄孔雀『沙沙』開屏時偏愛的振動特性相一致。
因此，凱恩及其同事將保存下來的死亡孔雀的冠毛，暴露在雄孔雀和雌孔雀社交行為的模擬展示中，比如翅膀抖動和沙沙地開屏。
我們驚訝地發現，二者真的一致。
這一切意味著，孔雀的頭冠是專門用來接收同類尾屏沙沙作響時所產生的振動的。
這樣一來，羽冠就像是接收單一聲音的特殊天線。
這項研究結果發生在《公共科學圖書館·綜合》期刊上。
研究人員還指出，至少存在分布於10個分類目中的35種其它鳥類，既有頭冠又有振動羽毛的表現。
很多這些觸覺方面的展示甚至都沒有得到很好的描述。
與凱恩一起進行這項研究的不列顛哥倫比亞大學的動物學家羅茲·達茲說到。
有些物種會在棲木上跳舞和振動，雌性會和雄性站在同一根棲木上，用腳等身體部位感受一切。
還有些鳥類會互相摩擦羽毛。
我們在這裡想表明的是，羽毛在社交展示中的感知功能可能比我們目前所理解的更為廣泛。
雌孔雀似乎真的能感覺到某隻雄孔雀的「激情」。
謝謝大家收聽科學美國人——60秒科學。
我是傑森·古德曼。