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1、职称英语考试宝典系列软件职称英语理工AB级阅读理解精讲(1) WhereHaveAlltheBeesGone? Scientistswhostudyinsectshavearealmysteryontheirhands.Allacrossthecountry,honeybeesareleavingtheirhivesandneverreturning.Researcherscallthisphenomenoncolony-collapse1disorder.Accordingtosurveysofb
2、eekeepersacrossthecountry,25to40percentofthehoneybeesintheUnitedStateshavevanishedfromtheirhivessincelastfall.Sofar,noonecanexplainwhy. Colonycollapseisaseriousconcernbecausebeesplayanimportantroleintheproductionofaboutone-thirdofthefoodsweeat.Astheyfe
3、ed,honeybeesspreadpollenfromflowertoflower.Withoutthisprocess,aplantcan’tproduceseedsorfruits. Now,agroupofscientistsandbeekeepershaveteameduptotrytofigureoutwhat’scausingthealarmingcollapseofsomanycolonies.Bysharingtheirexpertiseinhoneybeebehavior,hea
4、lth,andnutrition,teammembershopetofindoutwhat’scontributingtothedeclineandtopreventbeedisappearancesinthefuture. Itcouldbethatdiseaseiscausingthedisappearanceofthebees.Toexplorethatpossibility,JayEvans,aresearcherattheUnitedStatesDepartmentofAgricultur
5、e(USDA)BeeResearchLaboratory2,examinesbeestakenfromcoloniesthatarecollapsing.“Weknowwhatshealthybeeshouldlooklikeontheinside,andwecanlookforphysicalsignsofdisease,”hesays.Andbeesfromcollapsingcoloniesdon’tlookveryhealthy.“Theirstomachsareworndown,compar
6、edtothestomachsofhealthybees,”Evanssays.Itmaybethataparasiteisdamagingthebees’digestiveorgans.Theirimmunesystemsmaynotbeworkingastheyshould.Moreover,theyhavehighlevelsofbacteriainsidetheirbodies. Anothercauseofcolony-collapsedisordermaybecertainchemica
7、lsthatfarmersapplytokillunwantedinsectsoncrops,saysJerryHayes,chiefbeeinspectorfortheFloridaDepartmentofAgriculture3.Somestudies,hesays,suggestthatacertaintypeofinsecticideaffectsthehoneybee’snervoussystem(whichincludesthebrain)andmemory.“Itseemslikehon
8、eybeesaregoingoutandgettingconfusedaboutwheretogoandwhattodo,”hesays. Ifitturnsoutthatadiseaseiscontributingtocolonycollapse,bees’genescouldexplainwhysomecolonieshavecollapsedandothershavenot.Inanygroupofbeestherearemanydifferen