科学美国人60秒 SSS 拍打羽毛可能催化新物种（在线收听）

This is Scientific American's 60-second Science, I'm Christopher Intagliata.

这里是科学美国人——60秒科学系列，我是克里斯托弗·因塔格里塔。

Charles Darwin is most famous for his finches, from whose beaks he gleaned the idea that a single species might radiate into many.

查尔斯·达尔文最著名的是他的雀鸟，他从雀鸟喙中获得了一个想法，即一个物种可能辐射多个物种。

But he studied other attributes of birds, too—

但他也研究了鸟类的其他特性，

like the rhythmic sounds some species made during courtship by fluttering, shaking or rattling their feathers together.

比如某些物种会在求偶过程中通过让羽毛一起拍动、抖动或发出声响来产生有节奏的声音。

"Since Darwin, there's been this fact that birds produce sounds with wings and tails or flight feathers.

“自达尔文以来，鸟类通过翅膀、尾巴或飞羽发出声音这一事实就一直存在。

So there's species of manakins that do this sound; there's hummingbirds that do this sound."

侏儒鸟会这样发出声音；有些蜂鸟也会通过这种方式发出声音。”

Valentina Gómez-Bahamón is an evolutionary biologist and ornithologist at the Field Museum in Chicago.

芝加哥菲尔德博物馆的进化生物学家和鸟类学家瓦伦蒂娜·戈麦斯·巴汉姆说到。

She and her team have now observed that nonvocal-sound-production phenomenon in another type of bird: the fork-tailed flycatcher.

她和团队现已观察到另一种有非嗓音发声现象的鸟类：叉尾王霸鶲。

The researchers studied two groups of the birds in South America—

研究人员对南美洲的两组鸟进行了研究，

and recorded the birds making these fluttering sounds with their wings during morning courtship rituals...

并记录了这些鸟在早上求偶仪式中用翅膀发出的拍打声……

... and in combat between males.

……以及雄鸟打架时发出的声音。

One of the two flycatcher subspecies is migratory. The other stays put.

两种王霸鶲亚种中，一种是迁徙性的。另一种则待在原地。

And by carefully measuring the birds' feathers, the research team found that the migratory birds had longer, thinner feathers—presumably for some aerodynamic advantage.

通过仔细测量鸟的羽毛，研究团队发现迁徙鸟的羽毛更长、更薄，这可能是由于某种空气动力学优势。

But that altered feather shape also meant the birds' fluttering produced a different frequency.

但羽毛形状的改变也意味着鸟儿拍打翅膀产生了不同的频率。

Compare the migratory birds' flutter...

将迁徙鸟的拍打

... to the stationary birds'.

……与静止鸟的拍打进行对比。

"So basically what we think is that because of loss of migration,

“因此，基本上我们认为，由于缺少迁徙，

pressures for flight may influence the shape of the individual feathers to the point where the sound quality changes as well."

飞行压力可能会影响个别羽毛的形状，以至于音质也发生了变化。”

The details are in the journal Integrative & Comparative Biology.

研究详细内容发表在《综合与比较生物学》期刊上。

Gómez-Bahamón says they're still not certain what role the sounds play in day-to-day flycatcher life—if the birds do indeed even pay attention to them.

戈麦斯·巴汉姆表示，他们仍不确定这些声音在王霸鶲日常生活中扮演什么角色——如果它们真的注意到这些声音的话。

But she suspects the sounds may have some cultural importance to the birds.

但她怀疑这些声音可能对鸟类有一定的文化意义。

In which case, she says, the communication differences between the migratory and nonmigratory birds could further divide the two types of birds—

她表示，在这种情况下，迁徙和非迁徙鸟之间的交流差异可能进一步分化这两种鸟，

or in other words, give rise to the origin of species.

或者换句话说，引发物种起源。

Thanks for listening for Scientific American's 60-second Science. I'm Christopher Intagliata.

谢谢大家收听科学美国人——60秒科学。我是克里斯托弗·因塔利亚塔。