美国国家公共电台 NPR Scientists Find Out How Leaping Maggots Leap

 

AUDIE CORNISH, HOST:

This is the time of year when goldenrod blooms. It's that yellow flower you often see growing along highways. A scientist was recently studying goldenrods and discovered something phenomenal. As NPR's Nell Greenfieldboyce reports, it's a small creature that has no arms, legs or wings but nonetheless performs a remarkable¹ feat².

NELL GREENFIELDBOYCE, BYLINE³: Plants defend themselves from hungry insects, and Mike Wise studies that at Roanoke College in Virginia. A few years ago, he was dissecting⁴ tumor-like swelling⁵ on goldenrod. These growths form around little maggot-like things that are the larvae⁶ of developing flies.

MIKE WISE: And the larvae get as big, when they're full grown, as a small grain of rice.

GREENFIELDBOYCE: They look like bright orange tiny worms.

WISE: And generally I take the larvae out and put them in a little dish next to my microscope, and they barely move. They may wiggle around just a little bit.

GREENFIELDBOYCE: On this day, he'd spend about an hour removing a dozen or so. But then he looked in the dish, and they were gone.

WISE: I was wondering what was going on. And then I caught out of the corner of my eye a little bit of motion, a little orange larva jumping across my table.

GREENFIELDBOYCE: The larvae were leaping.

WISE: I looked on the floor, and there had been some that had jumped all the way to the wall.

GREENFIELDBOYCE: But how? They don't have anything critters normally use to jump. To understand this, he brought bouquets⁷ of goldenrod to Sheila Patek. She's a biologist at Duke University who studies small extremely fast things like the deadly strike of the mantis⁸ shrimp⁹ or the snapping bite of trap-jaw ants.

SHEILA PATEK: I know that sounds super quirky, but it turns out that this arena¹⁰ of biology is a very interesting one.

GREENFIELDBOYCE: Because these creatures do stuff that engineers can only dream of. Her lab filmed Wise's leaping larvae with some of the world's best high-speed cameras.

PATEK: You know, he'd get one out and put it in a tray. And I'd be like, oh, OK, yeah, well, there it is. And the next thing you know, this tiny little thing is curling up into a loop. And the next thing you know, it's gone.

GREENFIELDBOYCE: Curling up into a loop turns out to be critical. Patek says, if you were one of these little guys, you'd first curl up so that a special patch of hair on your head sticks to a patch of hair on your rear end. Then you'd need to squeeze fluid through your soft body to stiffen¹¹ up the part that's against the ground.

PATEK: And you keep doing that, and you keep doing that, and you keep doing that until suddenly you've generated enough force that it unsticks the hairs between your head and the tail, and you are suddenly airborne.

GREENFIELDBOYCE: The findings in the Journal of Experimental Biology have impressed Sarah Bergbreiter. She's a mechanical engineer at Carnegie Mellon University who says there's a lot of interest these days in robots that are soft instead of rigid¹² and clanky (ph).

SARAH BERGBREITER: One of the really cool things about it is that these are soft-bodied jumpers. That means they're squishy, and they can jump over 30 body lengths.

GREENFIELDBOYCE: She says that's comparable to fleas¹³, which we think of as great jumpers.

Nell Greenfieldboyce, NPR News.

1 remarkable   

adj.显著的，异常的，非凡的，值得注意的

参考例句：

• She has made remarkable headway in her writing skills.她在写作技巧方面有了长足进步。
• These cars are remarkable for the quietness of their engines.这些汽车因发动机没有噪音而不同凡响。

2 feat   

n.功绩；武艺，技艺；adj.灵巧的，漂亮的，合适的

参考例句：

• Man's first landing on the moon was a feat of great daring.人类首次登月是一个勇敢的壮举。
• He received a medal for his heroic feat.他因其英雄业绩而获得一枚勋章。

3 byline   

n.署名；v.署名

参考例句：

• His byline was absent as well.他的署名也不见了。
• We wish to thank the author of this article which carries no byline.我们要感谢这篇文章的那位没有署名的作者。

4 dissecting   

v.解剖（动物等）( dissect的现在分词 )；仔细分析或研究

参考例句：

• Another group was dissecting a new film showing locally. 另外一批人正在剖析城里上演的一部新电影。 来自辞典例句
• Probe into Dissecting Refraction Method Statics Processing under Complicated Surface Conditions. 不同地表条件下土壤侵蚀的坡度效应。 来自互联网

5 swelling   

n.肿胀

参考例句：

• Use ice to reduce the swelling. 用冰敷消肿。
• There is a marked swelling of the lymph nodes. 淋巴结处有明显的肿块。

6 larvae   

n.幼虫

参考例句：

• Larvae are parasitic on sheep.幼虫寄生在绵羊的身上。
• The larvae prey upon small aphids.这种幼虫以小蚜虫为食。

7 bouquets   

n.花束( bouquet的名词复数 )；（酒的）芳香

参考例句：

• The welcoming crowd waved their bouquets. 欢迎的群众摇动着花束。 来自《现代汉英综合大词典》
• As the hero stepped off the platform, he was surrounded by several children with bouquets. 当英雄走下讲台时，已被几名手持花束的儿童围住了。 来自《简明英汉词典》

8 mantis   

n.螳螂

参考例句：

• Praying mantis has two powerful claws like sharp knives.螳螂有一对强壮的爪子，它们像锋利的刀。
• In her mind,it was a female mantis,devouring her mates.她的意识中，是一只雌螳螂正吞咽她的配偶。

9 shrimp   

n.虾，小虾；矮小的人

参考例句：

• When the shrimp farm is built it will block the stream.一旦养虾场建起来，将会截断这条河流。
• When it comes to seafood,I like shrimp the best.说到海鲜，我最喜欢虾。

10 arena   

n.竞技场，运动场所；竞争场所，舞台

参考例句：

• She entered the political arena at the age of 25. 她25岁进入政界。
• He had not an adequate arena for the exercise of his talents.他没有充分发挥其才能的场所。

11 stiffen   

v.(使)硬，(使)变挺，(使)变僵硬

参考例句：

• The blood supply to the skin is reduced when muscles stiffen.当肌肉变得僵硬时，皮肤的供血量就减少了。
• I was breathing hard,and my legs were beginning to stiffen.这时我却气吁喘喘地开始感到脚有点僵硬。

12 rigid   

adj.严格的，死板的；刚硬的，僵硬的

参考例句：

• She became as rigid as adamant.她变得如顽石般的固执。
• The examination was so rigid that nearly all aspirants were ruled out.考试很严，几乎所有的考生都被淘汰了。

13 fleas   

n.跳蚤( flea的名词复数 )；爱财如命；没好气地（拒绝某人的要求）

参考例句：

• The dog has fleas. 这条狗有跳蚤。
• Nothing must be done hastily but killing of fleas. 除非要捉跳蚤，做事不可匆忙。 来自《简明英汉词典》