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1、Thesoaringnumberofgender-bendingchemicalsintheenvironmenthasdisturbingfertilityimplicationsforhumansandwildlife,scientistsarewarning.Theysaywildanimalsarebeing"feminised"byahostofcommonman-madepollutantswhichmimicthefemalesexhormoneoestrogenandescapeintoseas,rivers,theearthandairwhenwa
2、steisdisposedof.Thechemicals--foundinfoodpackaging,cleaningproducts,plastics,sewageandpaint--causegenitaldeformities,reducespermcountandeventurnmalesintofemales.Dozensofspecies--includingpolarbears,fish,whalesandotters--aresuffering,accordingtotheenvironmentalgroupChemTrust.Fishhavebee
3、nbadlyhitbyman-madegender-bendingchemicals.Inonestudy,halfthemalefishinBritishlowlandrivershadsignsofbeingfeminised.Butallvertebrates--orcreatureswithbackbones--havesimilarsexhormonereceptorsintheirbodies."Therefore,observationsinonespeciesmayservetohighlightpollutionissuesofconcernfor
4、othervertebrates,includinghumans,"thereportsays.
Itsauthor,GywnneLyons,aformergovernmentadviseronchemical-pollution,said:"someUrgentactionisneededtocontrolgender-bendingchemicalsandmoreresourcesareneededformonitoringwildlife.""Ifwildlifepopulationscrash,itwillbetoolate.Unlessenoughmale
5、scontributetothenextgenerationthereisarealthreattoanimalpopulationsinthelongterm."SomestudieshaveshownthatspermcountsintheWesthavefallenoverthepast30years.Othershaveshownariseinboysbornwithgenitaldeformities.Communitiesheavilypollutedwithhormone-disruptingchemicalsinRussia,CanadaandIta
6、lyhaveproducedtwiceasmanygirlsasboys.PassageTwo Biologicaldiversityhasbecomewidelyrecognizedasacriticalconservationissueonlysincethepasttwodecades.TherapiddestructionofthetropicalrainforestswhicharetheecosystemswiththehighestknownspeciesdiversityonEarthhasawakenedpeopletotheimport
7、anceandfragilityofbiologicaldiversity.Thehighrateofspeciesextinctionsintheseenvironmentsisjolting,butitisimportanttorecognizethesignificanceofbiologicaldiversityinallecosystems.Asthehumanpopulationcontinuestoexpand,itwillnegativelyaffectoneafteranotherofEarth'secosystems.Interrestria
