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1、TEXTONEWhenhoneybeesbegantodeserttheirhivesrecently,nevertoreturn,itthrewapiaristsintoapanic.Whatappearedtobeperfectlyhealthyadultbeeswouldfleetheirqueen,theyoungandtheirfoodstores.Insteadofransackingtheemptyhive,otherbeeswouldavoiditliketheplague.Yettherewasnothingo
2、bviouslywrong.Researchershavenowidentifiedthefirsttangibleclueinthemystery—arelativelynewvirus.ColonycollapsedisorderbecamewidespreadinAmericainthewinterof2006-07,whenaboutaquarterofthenation'sbeekeeperswereaffected,eachlosingbetween30%and90%oftheirwingedworkers.Bees
3、arevaluednotsomuchfortheirhoney,whichisworthsome$200mayearinAmerica,butfortheirworkinpollinatingcrops.Thisbringstheeconomysome$15billionayear,asapiaristsmovetheirhivestolandproducingfruit,vegetablesandnuts.Findingexactlywhycoloniescollapsehasbeentaxingthemindsofbothf
4、ederalanduniversityscientists.Therehavebeenfewbodiesonwhichtoconductautopsies.Thoseadultbeesthathavebeenfounddeadnearanabandonedhivehavebeenriddledwithalmosteverybeediseaseknowntoman.NowareportbyDianaCox-FosterofPennsylvaniaStateUniversityandhercolleagues,publishedin
5、theSeptember6thissueofScience,pointsthefingerattheIsraeliacuteparalysisvirus.Thelurgyinquestionwas,theresearcherssuggest,importedfromAustralia.Becausemanyfactorscouldbeactingtogethertocausebeecoloniestocollapse,DrCox-Fosterandhercolleaguesdecidedtoexamineeverythingth
6、eycouldfindwithintheemptyhives.Theycollectedsamplesfrominfectedhivesandcomparedthemnotonlywithsamplesfromapparentlyhealthyhivesbutalsowithananalysisofroyaljelly—abeesecretionfedtothelarvae—fromChina,whichhasnotbeenaffectedbythemysterydisorder.Fromtheirsamples,therese
7、archersextractedRNA—achemicalthatcarriesandhelpstodecodegeneticinformation.Theiranalysisrevealedthepresenceofvariousbacteria,fungiandvirusesthatwerelurkinginthehivesandtheroyaljelly.Theythenlookedtoseewhethertherewasanythingintheabandonedhivesthatwasnotfoundelsewhere
8、.Whattheyfoundwasavirusfirstidentifiedin2004intheMiddleEast.BeesinfectedwithIsraeliacuteparalysisvirusshiver,theirbodiesbecomefroze
