本期雅思听力提分训练素材：紧张的独角鲸不知道如何逃离，科学家发现(Stressed-Out Narwhals Don't Know Whether To Freeze Or Flee, Scientists Find)。本听力素材来自NPR，NPR新闻是美国的国家公共广播，纯公益，所以内容更加去纯粹，直击心灵。可作为雅思听力泛听训练的日常素材，坚持长期听，除了锻炼英语听力，还能积累雅思听力词汇。

英语泛听听力MP3素材下载：http://m.newstudy.cn/listinfo-156-0.html?/thread-418973-1-1.html

雅思听力泛听内容原文：Stressed-Out Narwhals Don't Know Whether To Freeze Or Flee, Scientists Find

RACHEL MARTIN, HOST:

It's Friday. And we all need some wonder in our lives. So let's talk about narwhals, shall we? What's a narwhal, you ask? They are whales with a long, spiral tusk, which makes them the unicorns of the sea. These elusive creatures live in the far north in an icy world. But it turns out narwhals are not cool under stress. Here's NPR's Nell GREenfieldboyce.

今天是星期五。我们都需要一些奇迹在我们的生活中。让我们谈论独角鲸，可以吗?你问什么是独角鲸?他们有长长的螺旋图斯克鲸鱼，这使得他们成为海中的独角兽。这些难以捉摸的生物生活在遥远的北方，在冰冷的世界里。但事实证明，独角鲸在水压下并不是冷酷的。这里是NPR的Nell Greenfieldboyce。

NELL GREENFIELDBOYCE, BYLINE: When a colleague contacted Terrie Williams about doing a study of narwhals...

TERRIE WILLIAMS: I said yes 'cause they're cool (laughter), you know? And I didn't know at all what I was getting into at that point.

GREENFIELDBOYCE: Williams is at the University of California, Santa Cruz. She's investigated how dolphins and seals swim and dive by putting wearable monitors on the animals. She was intrigued by the idea of trying it with a deep-diving whale that can go down more than a mile.

(SOUNDBITE OF NARWHAL CLICKS)

GREENFIELDBOYCE: This is the sound of narwhals off the east coast of Greenland.

That's where Williams joined scientists who were netting narwhals in shallow water to tag them. While the narwhals got tagged...

WILLIAMS: We were able to suction-cup electrodes on for the EKG, suction-cup our instrumentation on and have them swim with them anywhere from one day to four days at a time and collect thousands of dives.

GREENFIELDBOYCE: She was surprised to see that the dives that happened immediately after the narwhals were released from the net looked weird. The animal's heart rates plummeted, going from about 60 beats a minute...

(SOUNDBITE OF HEARTBEAT)

GREENFIELDBOYCE: ...To only three or four beats a minute. But at the same time, these narwhals were swimming away as fast as they could. Williams had never seen anything like it.

WILLIAMS: This is an unusual reaction to an unusual kind of threat.

GREENFIELDBOYCE: She says their heart rate suggested a freeze reaction to fear, even as they tried to flee. Her team's findings appear in the journal Science. Kristin Laidre is a narwhal researcher at the University of Washington. She says narwhals have long lived isolated from people in a distant, icy, often dark environment. So changes can have a big impact.

KRISTIN LAIDRE: So I think these data support that - you know, that this species is not used to any kind of disturbance. And it is definitely a physiological stressor for them.

GREENFIELDBOYCE: She says as the Arctic ice melts, there's more interest in oil and gas drilling and new shipping routes. So scientists need to understand how the narwhals might react. Nell Greenfieldboyce, NPR News.

(SOUNDBITE OF TAUK'S "HELLO NARWHAL")

雅思听力高频词汇

wearable 可穿戴

Stressed-Out 强调了

shipping routes 航线

plummeted 暴跌

isolated 分离

intrigued 感兴趣

gas drilling 气体钻井

flee 逃走

disturbance 骚乱

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