21世纪阅读 Grade9

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1、Theendofthestripypuzzle?作者：ImogenChampagne　时间：2014-04-21斑马为什么有条纹？MCTZEBRAS’stripes(条纹)havepuzzledscientistsaroundtheworldforcenturies.Whatisthebiologicalpurposeofbeingcoveredinblackandwhitestripes?Therearemanytheoriesthattrytoanswerthatquestion.CharlesDar

2、win,thefamousbiologist,thoughtthatZebras’stripeswereusedtoattractpartners.AlfredWallace,theBritishnaturalistandbiologistthoughtthestripeswereforcamouflage(伪装).Theymakethezebrashardtoseeatnightandcreateanopticalillusion(视错觉)intheday.Thisprotectsthemfrombei

3、nghuntedbylionsandotherfierceanimals.Butthezebras’realenemymightbeawholelotsmaller.AnewstudybyTimCarofromtheUniversityofCaliforniahascomeupwithanentirelynewtheoryonwhyzebrashavestripes.Hethinksthattheirstripeswillkeepbitingflies(螫蝇)awayfromthem.Caroandhis

4、colleaguestookadifferentroutetootherscientistswhohavestudiedzebras’stripes.Insteadoflookingjustatzebras,helookedatallequids(马科动物)(horses,zebrasandasses)andthedifferentpatternsoftheirstripes.Hefoundthatspeciesthatliveinareaswithdangerousfliesweremorelikely

5、tohavestripesallovertheirbodies.ZebrasliveinAfrica,wherebitingfliescancausegreatharmbybothpassingondiseasesandsuckingoutdangerousamountsofblood.Caroishappythattheyhaveansweredthequestionofwhyzebrashavestripes,butnowheisleftwithanotherquestion:whydon’tflie

6、slikestripes?“That’swhathappensinscience”,hetoldTheNewYorkermagazine.“Youansweronequestionanditleadstosixmore.”一、whilereading1.WhatdidDarwinthinkofzebras’strips?2.What’sthestrips’functionaccordingtoAlfred?3.WhatisTim’snewtheory?4.Howdobitingfliescauseharm

7、tootheranimals?5.Whatdoes“colleagues”meaninChinese?Choosethebestanswer:1.AccordingtoTimCaro,zebrashavestripesto_____.A.protectthemfrombeingseenB.attractpartnersC.createillusionsD.keepbitingfliesaway2.Caroandhiscolleaguesfoundevidenceby_____.A.examiningthe

8、stripsofzebrasB.stayingwithzebrasinAfricaC.observingzebrasatnightD.studyingallanimalswithstrips3.Thelastsentencesuggeststhat_____.A.scientistssometimesfinditdifficulttoanswerthequestionB.peoplecanneverreallyfindthea