【英语时差8，16】尾巴吱吱叫

 Don: [WHISTLING A BIRDSONG-LIKE TUNE¹]

Ya?l: Nice tune Don, but can you whistle with your tail like an Anna's hummingbird²?

D: Hummingbirds³ can whistle with their tails?

Y: Male Anna's hummingbirds, which live along the west coast of North America, can! Scientists in California discovered this when they were studying the birds' courtship behavior. They noticed that certain high-pitched chirps⁵ were produced only when males made rapid swooping⁶ courtship dives. The chirps were produced at the bottom of the dive when the birds flick⁷ open their tail feathers.

One of the scientists discovered that the two outermost⁸ feathers of the male hummingbird's tails had an unusual shape. He plucked these two strange feathers from one male and then let him go in front of a decoy female.

The plucked male saw the stuffed female and started a courtship display to impress her. He swooped⁹ into the dive in front of her, but this time there was no chirp⁴!

The curious scientist then attached one of the tail feathers to a long stick and found that if he spun¹⁰ it around fast enough, the feather started to hum.

By holding feathers in a wind-tunnel, he found that at wind speeds of forty-four miles per hour the modified tail feathers make high-pitched chirps like the ones heard during the flight displays.

D: Wow! So the tail feathers work like whistles?

Y: Actually, it's more like a clarinet. When you whistle, the tone is produced by air whistling through a constriction¹¹. The tail chirp is produced by vibration¹² of the feathers themselves, like the reeds in clarinet mouthpieces.

D: Neat! Maybe they should change the name from "Anna's hummingbird" to "Benny Goodman's hummingbird"Y: Oh, Don...!  

1 tune   

n.调子；和谐，协调；v.调音，调节，调整

参考例句：

• He'd written a tune,and played it to us on the piano.他写了一段曲子，并在钢琴上弹给我们听。
• The boy beat out a tune on a tin can.那男孩在易拉罐上敲出一首曲子。

2 hummingbird   

n.蜂鸟

参考例句：

• The hummingbird perches on a twig of the hawthorn.小蜂鸟栖在山楂树枝上。
• The hummingbird is the only bird that can fly backward.蜂鸟是唯一能倒退向后飞的鸟。

3 hummingbirds   

n.蜂鸟( hummingbird的名词复数 )

参考例句：

• Hummingbirds have discovered that nectar and pollen are very nutritious. 蜂鸟发现花蜜和花粉是很有营养的。
• Why do hummingbirds and gorillas both have backbones? 为什么蜂鸟和大猩猩都有脊骨？

4 chirp   

v.(尤指鸟)唧唧喳喳的叫

参考例句：

• The birds chirp merrily at the top of tree.鸟儿在枝头欢快地啾啾鸣唱。
• The sparrows chirp outside the window every morning.麻雀每天清晨在窗外嘁嘁喳喳地叫。

5 chirps   

鸟叫，虫鸣( chirp的第三人称单数 )； 啾； 啾啾

参考例句：

• The linnet chirps her vernal song. 红雀吱喳鸣叫着她春天的歌。
• She heard nothing but the chirps and whirrs of insects. 除了虫的鸣叫声外，她什么也没听见。

6 swooping   

俯冲，猛冲( swoop的现在分词 )

参考例句：

• The wind were swooping down to tease the waves. 大风猛扑到海面上戏弄着浪涛。
• And she was talking so well-swooping with swift wing this way and that. 而她却是那样健谈--一下子谈到东，一下子谈到西。

7 flick   

n.快速的轻打，轻打声，弹开；v.轻弹，轻轻拂去，忽然摇动

参考例句：

• He gave a flick of the whip.他轻抽一下鞭子。
• By a flick of his whip,he drove the fly from the horse's head.他用鞭子轻抽了一下，将马头上的苍蝇驱走。

8 outermost   

adj.最外面的，远离中心的

参考例句：

• He fired and hit the outermost ring of the target.他开枪射中了靶子的最外一环。
• The outermost electron is shielded from the nucleus.原子核对最外层电子的作用受到屏蔽。

9 swooped   

俯冲，猛冲( swoop的过去式和过去分词 )

参考例句：

• The aircraft swooped down over the buildings. 飞机俯冲到那些建筑物上方。
• The hawk swooped down on the rabbit and killed it. 鹰猛地朝兔子扑下来，并把它杀死。

10 spun   

v.纺，杜撰，急转身

参考例句：

• His grandmother spun him a yarn at the fire.他奶奶在火炉边给他讲故事。
• Her skilful fingers spun the wool out to a fine thread.她那灵巧的手指把羊毛纺成了细毛线。

11 constriction   

压缩； 紧压的感觉； 束紧； 压缩物

参考例句：

• She feels a constriction in the chest. 她胸部有压迫感。
• If you strain to run fast, you start coughing and feel a constriction in the chest. 还是别跑紧了，一咬牙就咳嗽，心口窝辣蒿蒿的！ 来自汉英文学 - 骆驼祥子

12 vibration   

n.颤动，振动；摆动

参考例句：

• There is so much vibration on a ship that one cannot write.船上的震动大得使人无法书写。
• The vibration of the window woke me up.窗子的震动把我惊醒了。