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A、There is still no exact explanation up to now. B、The birds have the acute sense about the weather. C、The birds can tell it fro
A、There is still no exact explanation up to now. B、The birds have the acute sense about the weather. C、The birds can tell it fro
admin
2010-07-24
71
问题
Animals do many different, amazing things to get through the winter. Some of them travel to other places where the weather is warmer or they can find food. Many birds travel in the fall. (32) Because the trip can be dangerous, some travel in large flocks. For example, geese fly in noisy, "V"-shaped groups. Other kinds of birds fly alone. (33) How do they know when it is time to leave for the winter? Scientists are still studying this. Many see transference as part of a yearly cycle of changes that a bird goes through. The cycle is controlled by changes in the amount of daylight and the weather. Most birds transfer shorter distances. But how do they find their way to the same place each year? (34) Birds seem to navigate like sailors once did, using the sun, moon and stars for direction. They also seem to have a compass in their brain for using the Earth’s magnetic field. Other animals transfer, too. (35) There are a few mammals, like some bats, and whales that travel in search of food each winter. Many fish transfer. They may swim south, or move into deeper, warmer water. Insects also transfer. Some butterflies and moths fly very long distances. For example, Monarch butterflies spend the summer in Canada and the Northern U. S. They transfer as far south as Merico for the winter. Most insects go much shorter distances. Many, like white ants and Japanese beetles, move downward into the soil. Earthworms also move down, some as far as six feet below the surface.
选项
A、There is still no exact explanation up to now.
B、The birds have the acute sense about the weather.
C、The birds can tell it from the moving of the sun.
D、The other birds in the flock send the information.
答案
A
解析
题干询问鸟类如何判断出什么时间迁徙过冬。文章中的论述为:How do they know when it is time to leave for the winter? Scientists are still studying this.由此推测该问题还没有确定的答案。
转载请注明原文地址:https://kaotiyun.com/show/EoA7777K
0
大学英语四级
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