Question

As they migrate, butterflies and moths choose the winds they want to fly with, and they change their body positions if they start floating in the wrong direction. This new finding suggests that insects may use some of the same methods that birds use for traveling long distances. Scientists have long thought that insects were simply at the mercy of the wind.

Fascinating as their skills of flight are, migrating behavior has been difficult to study in insects because many long distant trips happen thousands of feet above ground. Only recently have scientists developed technologies that can detect such little creatures at such great heights.

To their surprise, though, the insects weren't passive travelers on the winds. In autumn, for example, most light winds blew from the east, but the insects somehow sought out ones that carried them south and they positioned themselves to navigate directly to their wintering homes.

Even in the spring, when most winds flowed northward, the insects didn't always go with the flow. If breezes weren't blowing in the exact direction they wanted to go, the insects changed their body positions to compensate(补偿, 弥补). Many migrating birds do the same thing.

The study also found that butterflies and moths actively flew within the air streams that pushed them along. By adding flight speeds to wind speeds, the scientists calculated that butterflies and moths can travel as fast as 100 kilometers an hour. The findings may have real-world applications. With climate warming, migrating insects are growing in number. Knowing how and when these pests move could help farmers decide when to spray their crops.

1.What's the main idea of the text?

A．Insects migrate with the seasons.

B．The wind helps insects greatly in migrating.

C．Windsurfing insects have real direction.

D．Scientists have trouble in observing insects.

2.Scientists originally thought that _____.

A．insects always waited for their favorable winds

B．insects chose the winds they wanted to ride

C．insects were just blown about by the wind

D．insects positioned themselves in the winds

3.It is not easy to study the migrating behavior of the insects because ______.

A．the little creatures can fly very fast

B．their flight is long and high above ground

C．the wind's direction is hard to forecast

D．they have no regular migrating courses

4.According to the passage, the findings can ____

A．increase insects in number

B．instruct farmers when to spray their crops

C．prevent climate warming

D．help protect insects

Answer

1.C

2.C

3.B

4.B

【解析】

试题分析：本文讲述的科学家最近飞行蝴蝶和飞蛾在飞行的时候，并不是仍由大风吹来吹去，而是能够控制自己的飞行的方向和距离。这一研究结果有助于人们保护自己的作物。

1.C 主旨大意题。根据文章第一段前4行As they migrate, butterflies and moths choose the winds they want to fly with, and they change their body positions if they start floating in the wrong direction. This new finding suggests that insects may use some of the same methods that birds use for traveling long distances.可知蝴蝶这些动物实际上有很强的控制自己的身体的能力，并不是没有方向感，任由风吹乱飞的。故C正确。

2.C 细节题。根据第一段最后一句Scientists have long thought that insects were simply at the mercy of the wind.可知科学家原来因为蝴蝶是仍由大风吹来吹去的。故C正确。

3.B 细节题。根据文章第二段Fascinating as their skills of flight are, migrating behavior has been difficult to study in insects because many long distant trips happen thousands of feet above ground. Only recently have scientists developed technologies that can detect such little creatures at such great heights.可知这样的动物飞行得又高又远，这给科学家的研究带来了很大的困难。故B正确。

4.B 细节题。根据文章最后一句With climate warming, migrating insects are growing in number. Knowing how and when these pests move could help farmers decide when to spray their crops有助于农民们知道何时来保护自己的作物。可知B正确。

考点：考察科普类短文阅读