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Elephants don’t need cell phones to hold long distance conversations, their deep calls can travel miles. And although humans can’t always hear these vocalizations because of their low frequency, elephants produce them using the same mechanism² that lets humans speak and sing. That finding is in the journal Science.

Until now, scientists did not know whether the elephant made sound the way we speak or differently, such as the way cats purr. A human produces noises because the vocal¹ cords vibrate automatically when air flows past. But a cat must actively³ squeeze the muscles of its larynx to produce its deep, rhythmic⁴ purr.

When a zoo elephant died of natural causes, researchers took the animal’s larynx to their lab and ran air through it to find out which method elephants use to make sound. They could reproduce the large mammal’s low-frequency rumble⁵, which means that an elephant doesn’t need to actively control its larynx like a cat does. For those who contend that this is irrelevant⁶, “There’s a whole lot of irrelephants in the circus.”

Thanks for the minute for scientific American sixty seconds science. I'm Sophie Bushwick.

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收听单词发音

1 vocal
adj.直言不讳的；嗓音的；n.[pl.]声乐节目
参考例句：
The tongue is a vocal organ.舌头是一个发音器官。 Public opinion at last became vocal.终于舆论哗然。

2 mechanism
n.机械装置；机构，结构
参考例句：
The bones and muscles are parts of the mechanism of the body.骨骼和肌肉是人体的组成部件。 The mechanism of the machine is very complicated.这台机器的结构是非常复杂的。

3 actively
adv.积极地，勤奋地
参考例句：
During this period all the students were actively participating.在这节课中所有的学生都积极参加。 We are actively intervening to settle a quarrel.我们正在积极调解争执。

4 rhythmic
adj.有节奏的，有韵律的
参考例句：
Her breathing became more rhythmic.她的呼吸变得更有规律了。 Good breathing is slow,rhythmic and deep.健康的呼吸方式缓慢深沉而有节奏。

5 rumble
n.隆隆声；吵嚷；v.隆隆响；低沉地说
参考例句：
I hear the rumble of thunder in the distance.我听到远处雷声隆隆。 We could tell from the rumble of the thunder that rain was coming.我们根据雷的轰隆声可断定，天要下雨了。

6 irrelevant
adj.不恰当的，无关系的，不相干的
参考例句：
That is completely irrelevant to the subject under discussion.这跟讨论的主题完全不相关。 A question about arithmetic is irrelevant in a music lesson.在音乐课上，一个数学的问题是风马牛不相及的。