[求助] 请教下0301的一道阅读.... [复制链接]

tititalin
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电梯直达

楼主

发表于 2006-8-11 13:16:25 |只看该作者 |倒序浏览

麻烦各位给看看...
0301阅读的第15题...~~~

The origins of nest-building remain obscure, but current observation of nest-building
activities provide evidence of their evolution. Clues to this evolutionary process can be found in the activities of play and in the behavior and movements of birds during mating, such as incessant pulling at strips of vegetation or scraping of the soil. During the early days of the reproductive cycle, the birds seem only to play with the building materials. In
preparation for mating, they engage in activities that resemble nest-building, and continue these activities throughout and even after the mating cycle. Effective attempts at construction occur only after mating.
Although nest-building is an instinctive ability, there is considerable adaptability in
both site selection and use of materials, especially with those species which build quite elaborate constructions. Furthermore, some element of learning is often evident since younger birds do not build as well as their practiced elders. Young ravens, for example, first attempt to build with sticks of quite unsuitable size, while a jackdaw's first nest includes virtually any movable object. The novelist John Steinbeck recorded the contents of a young osprey nest built in his garden, which included three shirts, a bath towel, and
one arrow.
Birds also display remarkable behavior in collecting building materials. Crows have
been seen to tear off stout green twigs, and sparrowhawks will dive purposefully onto a branch until it snaps and then hang upside down to break it off. Golden eagles, over generations of work, construct enormous nests. One of these, examined after it had been dislodged by high winds, weighed almost two tons and included foundation branches almost two meters long. The carrying capacity of the eagles, however, is only relative to their size ant1 most birds are able to carry an extra load of just over twenty percent of their body weight.

15. Which of the following birds are mentioned as those that build nests that include unusual
objects?
(A) Ravens
(B) Ospreys
(C) Crows
(D) Sparrowhawks

我怎么没在原文发现?!.... 答案选的C....????
谢谢指教!

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cici1114
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沙发

发表于 2006-8-11 13:33:05 |只看该作者

Crows have been seen to tear off stout green twigs, and sparrowhawks will dive purposefully onto a branch until it snaps and then hang upside down to break it off

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