SSS 2009-04-10
时间:2019-01-08 作者:英语课 分类:Scientific American(四)月
This is Scientific American's 60-Second Science. I'm Karen Hopkin. This will just take a minute.
Thrill-seeking stunt 1 pilots spend years learning to perform maneuvers 2 that birds and bees know how to do from birth. Now a new study in the journal Science shows that, although birds and bugs 3 don’t go to flight school, it’s like they’re reading from the same manual when it comes to making turns.
If you’ve ever watched a hummingbird 4 or seen a bat chase after a moth 5, you know that critters that flap their wings to fly are amazing aerial acrobats 6, capable of hovering 7 near a flower or turning on a dime 8. But how do they do it? And does the tiniest fruit fly use the same tricks as a hummingbird or a bat?
The scientists studied videos of seven different kinds of winged beasts, from bluebottle flies to a cockatoo. And they found that they all used a technique called flapping counter-torque to recover from a turn. So, when a bird banks right, its left wing moves faster on the downstroke while the right is faster on the upstroke, which slows the animal’s rotation 9. And no matter what their size, critters with a similar wingspan to body length ratio, like a fruitfly and a hummingbird, need the same number of flaps to finish a turn. And you thought such aeronautical 10 insights would remain hidden until pigs fly.
Thanks for the minute for Scientific American's 60-Second Science. I'm Karen Hopkin
- Lack of the right food may stunt growth.缺乏适当的食物会阻碍发育。
- Right up there is where the big stunt is taking place.那边将会有惊人的表演。
- He suspected at once that she had been spying upon his maneuvers. 他立刻猜想到,她已经侦察到他的行动。 来自辞典例句
- Maneuvers in Guizhou occupied the Reds for four months. 贵州境内的作战占了红军四个月的时间。 来自辞典例句
- All programs have bugs and need endless refinement. 所有的程序都有漏洞,都需要不断改进。 来自《简明英汉词典》
- The sacks of rice were swarming with bugs. 一袋袋的米里长满了虫子。 来自《简明英汉词典》
- 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。
- A moth was fluttering round the lamp.有一只蛾子扑打着翅膀绕着灯飞。
- The sweater is moth-eaten.毛衣让蛀虫咬坏了。
- I was always fascinated by the acrobats at the circus. 我总是着迷于马戏团里的杂技演员。 来自《简明英汉词典》
- The acrobats' performance drew forth applause from the audience. 杂技演员的表演博得了观众的掌声。 来自《简明英汉词典》
- The helicopter was hovering about 100 metres above the pad. 直升机在离发射台一百米的上空盘旋。
- I'm hovering between the concert and the play tonight. 我犹豫不决今晚是听音乐会还是看戏。
- A dime is a tenth of a dollar.一角银币是十分之一美元。
- The liberty torch is on the back of the dime.自由火炬在一角硬币的反面。
- Crop rotation helps prevent soil erosion.农作物轮作有助于防止水土流失。
- The workers in this workshop do day and night shifts in weekly rotation.这个车间的工人上白班和上夜班每周轮换一次。
- Many of the pilots were to achieve eminence in the aeronautical world. 这些飞行员中很多人将会在航空界声名显赫。 来自辞典例句
- The advent of aircraft brought with it aeronautical engineering. 宇宙飞船的问世导致了航天工程的出现。 来自辞典例句