5.Scientists have long wondered what benefit zebras might get from their fancy black-and-white coats.Those stripes(條紋) 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 (類別) equus lived.Some of these equines(馬科動物) have stripes,including zebras and asses(驢) 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(偽裝) 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 本文是一篇科教類閱讀,屬于說明文,科學(xué)家們一直想知道斑馬可能會受益于他們的黑白外衣,最近的一項研究發(fā)現(xiàn),這些條紋可能是防止蚊蟲的叮咬的最有效方法.本文以此展開談?wù),主要講述了斑馬黑白條紋的作用.
解答 59.答案:C.細(xì)節(jié)理解題.根據(jù)"Those stripes(條紋) may be most useful as protection from biting flies,a recent study concludes."可知,最近地一項研究得出結(jié)論,這些條紋是為了防止蚊蟲叮咬的.故選C.
60.答案:B.句意理解題.此句句意為"這些想法是無意義的".根據(jù)"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,條紋出現(xiàn)來幫助動物避免被蚊子咬等.故此句放在該句之前符合語境.故選B.
61.答案:C.推理判斷題.根據(jù)"Inns Cuthill is a biologist at England's University of Bristol.He finds the new study"convincing"."可知,Cuthill開始相信這個學(xué)說了.故選C.
62.答案:A.主旨大意題.根據(jù)全文內(nèi)容,本文主要講述了斑馬有黑白條紋的原因.故A符合文章內(nèi)容.故選A.
點評 本文是一篇科教類閱讀,題目涉及多道細(xì)節(jié)理解題,句意理解題,推理判斷題,主旨大意題.做題時學(xué)生應(yīng)仔細(xì)閱讀原文,把握文章主要內(nèi)容,聯(lián)系文章上下文內(nèi)容并結(jié)合所給選項含義,從中選出正確答案,一定要做到有理有據(jù),切忌胡亂猜測.