5.Scientists have long wondered what benefit zebras might get from their fancy black-and-white coats.Those stripes(条纹) may be most useful as protection from biting flies,a recent study concludes.
Biologists studied zebras and other closely related African animals.They tested five popular ideas about how the stripes might function.No evidence emerged to support most of these notions,Tim Caro told Science News.As a wildlife biologist,he works at the University of California,Davis.
①.Some scientists had proposed those stripes help zebras hide from predators,such as lions,or confuse them.Still others suggested that those stripes might offer some cooling or help the animals in forming social groups.
②.Instead,the stripes appear to help the animals avoid the bite of bloodthirsty flies.This finding supports some studies had found signs that flies prefer solids to stripes when hunting for a landing place.
③.To test all of the theories,Caro's group used geographic information.They looked at where in Africa the 20different types of animals belonging to the genus (类别) equus lived.Some of these equines(马科动物) have stripes,including zebras and asses(驴) with striped legs.Others are stripe-free.These include other asses and wild horses.
The scientists found no connection between stripes and whether the animals lived in woodsy areas.That suggests stripes don't camouflage(伪装) zebras in those places.
The scientists also saw no link between where striped animals lived and where lions hunted.In the studies,researchers found that lions ate plenty of zebras.The new observations suggest stripes don't confuse the predators.
The experts also looked for---and found---no evidence that stripes cool the zebras or help them recognize each another when forming social groups.
④.Striped animals often live in places where the environment is just right much of the year for biting flies to flourish.In those areas,horseflies,tsetse flies and other biting flies spread fatal diseases to zebras and horses.That connection now suggests stripes may help zebras reduce the number of bites and the infections they can spread.
The study doesn't answer how the zebra got its stripes in the first place,Caro admits.Science may never know.Inns Cuthill is a biologist at England's University of Bristol.He finds the new study"convincing".Until now,Cuthill's favorite hypothesis had been that zebra stripes confused predators.It's too soon to say the mystery of the zebra's stripes has been solved,he notes.But he says that keeping flies away is now probably"the leading contender".
59.According to the recent study,the stripes in zebras may be used toC.
A.offer some cooling when it is hot
B.help them hide from or confuse predators
C.protect themselves from being bitten by flies
D.help them in forming social groups
60.The missing sentence"None of those ideas make sense."can be put inB.
A.①B.②C.③D.④
61.It can be inferred from the passage thatC.
A.the study answers how the zebra got its stripes
B.flies prefer solids to stripes when seeking a landing place
C.Cuthill now tends to believe the new theory
D.the mystery of the zebra's stripes will be solved soon
62.Which of the following can best serve as the title of this passage?A
A.One Plus to Wearing Stripes
B.How Does Zebra Get Stripes
C.Mystery Solved
D.Zebra's Stripes.
分析 本文是一篇科教类阅读,属于说明文,科学家们一直想知道斑马可能会受益于他们的黑白外衣,最近的一项研究发现,这些条纹可能是防止蚊虫的叮咬的最有效方法.本文以此展开谈论,主要讲述了斑马黑白条纹的作用.
解答 59.答案:C.细节理解题.根据"Those stripes(条纹) may be most useful as protection from biting flies,a recent study concludes."可知,最近地一项研究得出结论,这些条纹是为了防止蚊虫叮咬的.故选C.
60.答案:B.句意理解题.此句句意为"这些想法是无意义的".根据"Instead,the stripes appear to help the animals avoid the bite of bloodthirsty flies.This finding supports some studies had found signs that flies prefer solids to stripes when hunting for a landing place."可知,相反,条纹出现来帮助动物避免被蚊子咬等.故此句放在该句之前符合语境.故选B.
61.答案:C.推理判断题.根据"Inns Cuthill is a biologist at England's University of Bristol.He finds the new study"convincing"."可知,Cuthill开始相信这个学说了.故选C.
62.答案:A.主旨大意题.根据全文内容,本文主要讲述了斑马有黑白条纹的原因.故A符合文章内容.故选A.
点评 本文是一篇科教类阅读,题目涉及多道细节理解题,句意理解题,推理判断题,主旨大意题.做题时学生应仔细阅读原文,把握文章主要内容,联系文章上下文内容并结合所给选项含义,从中选出正确答案,一定要做到有理有据,切忌胡乱猜测.