It might be easy to imagine that the more crowded a bird flock(群) becomes, the slower the birds fly. But it has been proven that the bigger a bird flock becomes, the faster the birds will fly. The discovery was made by scientists from Sweden’s Lund University. They took a look at the flying speed of birds in an effort to find what influenced how fast they would fly.
Most of the findings didn’t surprise the researchers. A bird’s weight and its wing shape, wind speed and direction, and the purpose of the flight all indeed influenced its flying speed. But the scientists found that the size of the flock had a strong effect on the flying speed, which had not been expected. The scientist Anders Hedenstrm expressed surprise at the discovery as it has usually been ignored in studies on birds.
Anders Hedenstrm and his partner Susanne Akesson collected their data on Sweden’s Öland Island. There they studied birds’ physical characteristics(特征), counted flock populations, and recorded their speeds during flying. To know the birds’ speed while flying, they used a tool that can also gauge important characteristics of wind, including speed and direction. They were able to measure the speed of different kinds of large flocks. The researchers’ results showed that bigger flocks fly faster no matter what kind of bird species they belong to. Why that’s the case is the next question they hope to answer.
The researchers also said that large flocks are made up of largersized birds, which move at faster speed than smaller birds. In a large flock, it is easier to take advantage of the turbulence(湍流) that occurs behind other birds, especially when flying in formation(队形), like geese and other birds do. Using the turbulence makes it easier to maintain higher speed.
【解题导语】 原本人们认为鸟群的数目越大，就会飞的越慢，而最新的研究却得出了完全相反的结果。这是为什么呢？
1．What does Paragraph 1 mainly tell us?
A．The bigger the bird flock is, the faster the birds fly.
B．The bigger the bird flock is, the slower the birds fly.
C．What affects birds’ flying speed didn’t interest people.
D．There was no further progress in studying birds’ flying speed.
A 解析：段落大意题。根据第一段的内容可知，最新的研究表明：并非鸟群的数目越大，飞行速度越慢，而是恰好相反。
2．What does the underlined word “gauge” in Paragraph 3 probably mean?
A．Measure. B．Affect.
C．Change. D．Control.
A 解析：词义猜测题。根据划线词后面的They were able to measure the speed of different kinds of large flocks.可知，gauge意为“测量”。
3．What can be learned from the last paragraph?
A．Birds are naturalborn flyers.
B．Bigger birds fly slower than smaller ones.
C．Turbulence helps birds maintain higher speed.
D．The goose is the slowest flying bird in the world.
C 解析：推理判断题。根据最后一段的内容可知，鸟类可以利用大气湍流维持飞行速度。
