先熱身后鳴禽會唱得更好

熱身后鳴禽會唱得更好

Just like an opera singer or pop star would never enter the stage or recording studio without stretching their vocal cords, songbirds appear to practice their singing early in the morning before they put on a full performance a little later on, a new study finds.

一項新的研究發(fā)現，就像歌劇演唱家或流行歌手在進入舞臺或錄音室之前必須伸展他們的聲帶一樣，鳴禽似乎在清晨練習它們的歌唱，然后再在稍晚的時候進行完整的表演。

The research was published in the journal Animal Behaviour.

這項研究發(fā)表在《動物行為》雜志上。

Scientists have always been curious as to why birds sing so vigorously and so loudly so early in the morning.

科學家們一直很好奇為什么鳥兒在清晨那么有力、那么大聲地唱歌。

“A bunch of reasons have been proposed as to why birds sing most intensely during the dawn chorus,” first author Jason Dinh, a biology PhD student who did the study while an undergraduate at Duke University, told Treehugger. “For example, the temperature might be best for sound transmission, the efficacy of foraging might be low at dawn so birds might invest in other activities like singing, or the rate of territory intrusion is highest at dawn so birds need to sing more to defend their territory.”

該研究的第一作者賈森•丁在接受《擁抱樹》采訪時表示:“關于鳥類為何在黎明時分唱腔最為強烈，人們提出了很多理由。”他是杜克大學的一名生物學博士，同時也是這項研究的本科生。“例如，溫度可能最適合聲音傳播，黎明時覓食的效率可能較低，所以鳥兒可能會投入到唱歌等其他活動中，或者在黎明時入侵領地的比率最高，所以鳥兒需要更多地唱歌來保護它們的領地。”

The swamp sparrow has a simple song of up to five notes that it repeats 5 to 10 times a second. mirceax / Getty Images

But researchers at Duke were interested in a “warm-up hypothesis” that the intense pre-dawn trilling puts them in best form for singing later in the morning.

但杜克大學的研究人員對一種“熱身假說”很感興趣，即黎明前強烈的顫音能使它們處于最佳狀態(tài)，適合在早上晚些時候唱歌。

“I think warming up might be one explanation to the dawn chorus, but it is certainly not the only explanation! There are probably several benefits driving birds to sing so intensely at dawn,” Dinh said.

“我認為熱身可能是黎明合唱的一種解釋，但肯定不是唯一的解釋!”讓鳥兒在黎明時如此興奮地唱歌可能有幾個好處。”

To test the warming-up theory, researchers recorded 11 male swamp sparrows for several mornings each between 2 a.m. and noon. The swamp sparrow’s song is a simple trill of just five notes or fewer. It repeats five to 10 times a second and sounds a bit “like a melodious police whistle,” co-author Stephen Nowicki, a biology professor at Duke, said in a statement.

為了驗證熱身理論，研究人員記錄了11只雄性沼澤麻雀在早上2點到中午之間的活動。沼澤麻雀的歌聲是一種簡單的顫音，只有五個音符或更少。杜克大學生物學教授、合著者斯蒂芬·諾維奇在一份聲明中說，這種聲音每秒重復5到10次，聽起來有點“像悠揚的警察哨聲”。

Practice Makes Perfect

熟能生巧

The researchers measured each bird’s trill rate and vocal range throughout the mornings. Although swamp sparrows can start singing as early as 2:30 a.m., they aren’t in their best voice as soon as they open their beaks, researchers found.

研究人員測量了每只鳥在早晨的顫音頻率和聲音范圍。研究人員發(fā)現，盡管沼澤麻雀早在凌晨2:30就能開始唱歌，但它們一張開嘴并無法發(fā)出最好的聲音。

Recording analysis showed that the birds start off singing slower or with limited range. They practice hundreds of times, gradually picking up tempo and reaching higher and lower pitch until they perfect their songs right after dawn. The more they practice, the better they sound.

錄音分析顯示，這些鳥開始時的鳴叫速度較慢或范圍有限。他們練習了數百次，逐漸加快節(jié)奏，提高和降低音調，直到他們的歌曲在黎明之后變得完美。他們練習得越多，聽起來就越好。

“They’re able to perform more difficult songs later in the morning,” Dinh said.

“他們可以在早上晚些時候演奏更困難的歌曲，”Dinh說。

It’s difficult to directly compare birds to humans, said Dinh, but warming up may help birds get their blood flowing and help their temperature increase so their bodies are prepared for the physiological demands of singing.

Dinh說，很難直接將鳥類和人類進行比較，但是熱身可以幫助鳥類血液流動，幫助它們提高體溫，這樣它們的身體就可以為歌唱的生理需求做好準備。

“It is physically challenging to sing high performance songs,” Dinh explained. But the payoff may come in romantic and defensive ways.

“唱高質量的歌曲對身體是一項挑戰(zhàn)，”Dinh解釋說。但回報可能是浪漫和防御的方式。

“In swamp sparrows, we know that females are more attracted to high performance songs. Furthermore, high performance songs are more threatening to rival males."

“我們知道，在沼澤麻雀中，雌鳥更喜歡高效的歌聲。此外，高表現力的歌曲對雄性競爭對手更具威脅性。”