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1、课时作业(二十六) 题型组合练——练规范(阅读理解＋语法填空＋短文改错＋书面表达)限时：55分钟Ⅰ.阅读理解A“Deextinction”，theideathatextinct(绝种的)animalscanbebroughtbackthroughcloningorgenetic(基因的)engineering，hasattractedtheinterestofasmallgroupofscientists.ThetopichasmadethecoverofNationalGeographicMagazine.Supporter
2、ssaytheyaredoingitformoralreasonsandbecausewe“miss”theextinctanimals.Theyblamehumanexploitation(suchastrapping，hunting,habitatdestruction)oftheextinctanimals,buttheirplans,thoughtheysoundexciting,areexploitationinanotherform.Consideringtheimperfectscienceofcloning,d
3、eextinctionwouldcauseanimalssuffering.Mostanimalsbornofsuchexperimentswouldsufferseriousdiseases,dyingsoonafterbirthorhavingashortenedlifetime.SpanishandFrenchscientistsworkedforyearstobringthePyreneanibex,aspeciesofwildgoat,backfromextinctionbycloning.In2009,theysu
4、cceededonlyinproducingasickbabygoatthatdied10minutesafterbirth.Fortheseanimalstobeborn,otheranimalswouldliveincaptivity,inalaborelsewhere,andserveasmothersubstitutes(代用品)，routinelyhavingoperationsaspartofthecloningprocess.Forexample,elephantswouldbekeptincaptivityto
5、carrywoollymammoth(猛犸)babiesfornearlytwoyears.Suchexperimentsoftenleadtootheranimals'unhappinessaswell.Ifextinctanimalsaresuccessfullybroughtback,wherewouldtheygo?Theiroriginalhabitatshavedevelopedandchangedwithoutthem.Theyareunlikelytosurviveinthenaturalenvironment
6、,but,iftheydomanagetosurvive,theywillaffecttheirenvironmentinunpredictableways,presentinganewthreattotheecologicalsystem.Iftheanimalsbornthroughdeextinctionarestuckinzoosandmuseumsinstead,whatgoodisthat?Itisexploitation,notasolution.Itwouldbebettertoapplycreativethi
7、nkingaboutprotectiontothereallifeproblemsoftoday'sworld.Deextinctiontakesattentionawayfromthedifficultsituationofendangeredanimals.DiscussionsaboutwoollymammothcloningdonothingtostoptheillegalkillingsofendangeredwildAfricanelephants.Moneywouldbebetterusedtopreventhu
8、manconflictwithwildlifeandtheirecosystems.Let'skeepdeextinctionintheworldofsciencefiction,learnfromourfailedpast,andprotectwildanimalsandt
