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首页 寂静的春天_英文版Silent Spring.pdf

寂静的春天_英文版Silent Spring.pdf

寂静的春天_英文版Silent Spring.pdf

上传者: 诸葛飘宇 2017-03-03 评分 0 0 0 0 0 0 暂无简介 简介 举报

简介:本文档为《寂静的春天_英文版Silent Springpdf》,可适用于工程科技领域,主题内容包含SILENTSPRINGRACHELCARSON(ONESINGLEBOOKWHICHBROUGHTTHEISSUEOFPESTICIDESCENT符等。

SILENTSPRINGRACHELCARSON(ONESINGLEBOOKWHICHBROUGHTTHEISSUEOFPESTICIDESCENTERSTAGEWITHMASSSCALEPOISONINGOFTHELANDWITHPESTICIDESANDWITHTHOUSANDSOFFARMERSCOMMITTINGSUICIDETHISBOOKISESSENTIALFORPUBLICRESEARCHININDIA)ContntsAcknowldgmntsixForwordxiAFablforTomorrowThObligationtoEndurElixirsofDathSurfacWatrsandUndrgroundSasRalmsofthSoilEarthrsquosGrnMantlNdlssHaocAndNoBirdsSingRirsofDathIndiscriminatlyfromthSkisByondthDramsofthBorgiasThHumanPricThroughaNarrowWindowOninEryFourNaturFightsBackThRumblingsofanAalanchThOthrRoadListofPrincipalSourcsIndxAcknowldgmntsINALETTERwrittninJanuary,OlgaOwnsHuckinstoldmofhrownbittrxprincofasmallworldmadliflss,andsobroughtmyattnti<spanclass='wran'>ons<span>harplybacktoaproblmwithwhichIhadlongbnconcrndIthnralizdImustwritthisbookDuringthyarssincthnIharcidhlpandncouragmntfromsomanypoplthatitisnotpossibltonamthmallhrThoswhohafrlyshardwithmthfruitsofmanyyarsrsquoxprincandstudyrprsntawidarityofgornmntagncisinthisandothrcountris,manyunirsitisandrsarchinstituti<spanct,MalcolmMHargras,MD,ofthMayoClinic,WCHupr,MD,ofthNationalCancrInstitut,CJKrswillofthFishrisRsarchBoardofCanada,OlausMuriofthWildrnssSocity,ADPickttofthCanadaDpartmntofAgricultur,ThomasGScottofthIllinoisNaturalHistorySury,ClarncTarzwllofthTaftSanitaryEnginringCntr,andGorgJWallacofMichiganStatUnirsityErywritrofabookbasdonmanydirsfactsowsmuchtothskillandhlpfulnssoflibrariansIowsuchadbttomany,butspciallytoIdaKJohnstonofthDpartmntofthIntriorLibraryandtoThlmaRobinsonofthLibraryofthNationalInstitutsofHalthAsmyditor,PaulBrookshasginstadfastncouragmntorthyarsandhaschrfullyaccommodatdhisplanstopostponmntsanddlaysForthis,andforhisskilldditorialjudgmnt,IamrlastinglygratfulIhahadcapablanddotdassistancinthnormoustaskoflibraryrsarchfromDorothyAlgir,JannDais,andBttHanyDuffAndIcouldnotpossiblyhacompltdthtask,undrcircumstancssomtimsdifficult,xcptforthfaithfulhlpofmyhouskpr,IdaSprowFinally,Imustacknowldgourastindbtdnsstoahostofpopl,manyofthmunknowntomprsonally,whohanrthlssmadthwritingofthisbooksmworthwhilThsarthpoplwhofirstspokoutagainstthrcklssandirrsp<spanclass='wran'>ons<span>iblpoisoningofthworldthatmansharswithallothrcraturs,andwhoarnnowfightingththousandsofsmallbattlsthatinthndwillbringictoryforsanityandcomm<spanclass='wran'>ons<span>nsinouraccommodationtothworldthatsurroundsusRACHELCARSONForwordIN,whnRachlCarsonundrtooktowritthbookthatbcamSilntSpring,shwasfiftyyarsoldShhadspntmostofhrprofssionallifasamarinbiologistandwritrwiththUSFishandWildlifSricButnowshwasaworldfamousauthor,thankstothfabuloussuccssofThSaAroundUs,publishdsnyarsbforRoyaltisfromthisbookanditssuccssor,ThEdgofthSa,hadnabldhrtodotfulltimtohrownwritingTomostauthorsthiswouldsmlikanidalsituation:anstablishdrputation,frdomtochoosonrsquosownsubjct,publishrsmorthanradytocontractforanythingonwrotItmighthabnassumdthathrnxtbookwouldbinafildthatoffrdthsamopportunitis,thsamjoyinrsarch,asdiditsprdcssorsInddshhadsuchprojctsinmindButitwasnottobWhilworkingforthgornmnt,shandhrscintificcollagushadbcomalarmdbythwidspradusofDDTandothrlonglastingpois<spanclass='wran'>ons<span>insocalldagriculturalcontrolprogramsImmdiatlyaftrthwar,whnthsdangrshadalradybnrcognizd,shhadtridinaintointrstsommagazini<spanclass='wran'>nana<span>rticlonthsubjctAdcadlatr,whnthsprayingofpsticidsandhrbicids(somofthmmanytimsastoxicasDDT)wascausingwholsaldstructionofwildlifanditshabitat,andclarlyndangringhumanlif,shdciddshhadtospakoutAgainshtridtointrstthmagazinsi<spanclass='wran'>nana<span>rticlThoughbynowshwasawllknownwritr,thmagazinpublishrs,faringtolosadrtising,turndhrdownForxampl,amanufacturrofcanndbabyfoodclaimdthatsuchanarticlwouldcausldquounwarrantdfarrdquotomothrswhousdhisproduct(ThonxcptionwasThNwYorkr,whichwouldlatrsrializpartsofSilntSpringinadancofbookpublication)SothonlyanswrwastowritabookmdashbookpublishrsbingfrofadrtisingprssurMissCarsontridtofindsomonlstowritit,butatlastshdciddthatifitwrtobdon,shwouldhatodoithrslfManyofhrstrongstadmirrsqustiondwhthrshcouldwritasalablbook<spanclass='wran'>ons<span>uchadrarysubjctShshardthirdoubts,butshwntahadbcausshhadtoldquoThrwouldbnopacform,rdquoshwrottoafrind,ldquoifIkptsilntrdquoSilntSpringwasorfouryarsinthmakingItrquirdarydiffrntkindofrsarchfromhrpriousbooksShcouldnolongrrcountthdlightsofthlaboratorisatWoodsHolorofthmarinrockpoolsatlowtidJoyinthsubjctitslfhadtobrplacdbyasnsofalmostrligiousddicationAndxtraordinarycourag:duringthfinalyarsshwasplagudwithwhatshtrmdldquoawholcataloguofillnsssrdquoAlsoshknwrywllthatshwouldbattackdbythchmicalindustryItwasnotsimplythatshwasopposingindiscriminatusofpois<spanclass='wran'>ons<span>butmdashmorfundamntallymdashthatshhadmadclarthbasicirrsp<spanclass='wran'>ons<span>ibilityofanindustrializd,tchnologicalsocitytowardthnaturalworldWhnthattackdidcom,itwasprobablyasbittrandunscrupulousasanythingofthsortsincthpublicationofCharlsDarwinrsquosOriginofSpcisacnturybforHundrdsofthousandsofdollarswrspntbythchmicalindustryi<spanclass='wran'>nana<span>ttmpttodiscrditthbookandtomalignthauthormdashshwasdscribdasanignorantandhystricalwomanwhowantdtoturntharthortothinsctsThsattacksfortunatlybackfirdbycratingmorpublicitythanthpublishrpossiblycouldhaafforddAmajorchmicalcompanytridtostoppublicationonthgroundsthatMissCarsonhadmadamisstatmntaboutonofthirproductsShhadnrsquot,andpublicationprocdd<spanclass='wran'>ons<span>chdulShhrslfwassingularlyunmodbyallthisfurorManwhil,asadirctrsultofthmssaginSilntSpring,PrsidntKnndystupaspcialpanlofhisScincAdisoryCommitttostudythproblmofpsticidsThpanlrsquosrport,whnitappardsommonthslatr,wasacompltindicationofhrthsisRachlCarsonwasrymodstabouthraccomplishmntAsshwrottoaclosfrindwhnthmanuscriptwasnaringcompltion:ldquoThbautyofthliingworldIwastryingtosahasalwaysbnupprmostinmymindmdashthat,andangratthsnslss,brutishthingsthatwrbingdonNowlcanbliIhaatlasthlpdalittlrdquoInfact,hrbookhlpdtomakcology,whichwasanunfamiliarwordinthosdays,onofthgratpopularcaussofourtimItldtonironmntallgislationatryllofgornmntTwntyfiyarsaftritsoriginalpublication,SilntSpringhasmorthanahistoricalintrstSuchabookbridgsthgulfbtwnwhatCPSnowcalldldquothtwocultursrdquoRachlCarsonwasaralistic,wlltraindscintistwhopossssdthinsightandsnsitiityofapotShhadanmotionalrsp<spanclass='wran'>ons<span>tonaturforwhichshdidnotapologizThmorshlarnd,thgratrgrwwhatshtrmdldquothsnsofwondrrdquoSoshsuccddinmakingabookaboutdathaclbrationoflifRradinghrbooktoday,onisawarthatitsimplicati<spanclass='wran'>ons<span>arfarbroadrthanthimmdiatcrisiswithwhichitdaltByawakingustoaspcificdangrmdashthpoisoningoftharthwithchmicalsmdashshhashlpdustorcognizmanyothrways(somlittlknowninhrtim)inwhichmankindisdgradingthqualityoflifonourplantAndSilntSpringwillcontinutormindusthatinourororganizdandormchanizdag,indiidualinitiatiandcouragstillcount:changcanbbroughtabout,notthroughincitmnttowaroriolntrolution,butrathrbyaltringthdirctionofourthinkingaboutthworldwliinAFablforTomorrowTHEREWASONCEatowninthhartofAmricawhralllifsmdtoliinharmonywithitssurroundingsThtownlayinthmidstofachckrboardofprosprousfarms,withfildsofgrainandhillsidsoforchardswhr,inspring,whitcloudsofbloomdriftdabothgrnfildsInautumn,oakandmaplandbirchstupablazofcolorthatflamdandflickrdacrossabackdropofpinsThnfoxsbarkdinthhillsanddrsilntlycrossdthfilds,halfhiddninthmistsofthfallmorningsAlongthroads,laurl,iburnumandaldr,gratfrnsandwildflowrsdlightdthtralrrsquosythroughmuchofthyarEninwintrthroadsidswrplacsofbauty,whrcountlssbirdscamtofdonthbrrisandonthsdhadsofthdridwdsrisingabothsnowThcountrysidwas,infact,famousforthabundancandarityofitsbirdlif,andwhnthfloodofmigrantswaspouringthroughinspringandfallpopltraldfromgratdistancstoobsrthmOthrscamtofishthstrams,whichflowdclarandcoldoutofthhillsandcontaindshadypoolswhrtroutlaySoithadbnfromthdaysmanyyarsagowhnthfirststtlrsraisdthirhouss,sankthirwlls,andbuiltthirbarnsThnastrangblightcrptortharaandrythingbgantochangSomilspllhadsttldonthcommunity:mystriousmaladisswptthflocksofchicknsthcattlandshpsickndanddidErywhrwasashadowofdathThfarmrsspokofmuchillnssamongthirfamilisInthtownthdoctorshadbcommorandmorpuzzldbynwkindsofsicknssapparingamongthirpatintsThrhadbnsralsuddnandunxplainddaths,notonlyamongadultsbutnamongchildrn,whowouldbstricknsuddnlywhilatplayanddiwithinafwhoursThrwasastrangstillnssThbirds,forxamplmdashwhrhadthygonManypoplspokofthm,puzzldanddisturbdThfdingstati<spanclass='wran'>ons<span>inthbackyardswrdsrtdThfwbirdssnanywhrwrmoribundthytrmbldiolntlyandcouldnotflyItwasaspringwithoutoicsOnthmorningsthathadoncthrobbdwiththdawnchorusofrobins,catbirds,dos,jays,wrns,andscorsofothrbirdoicsthrwasnownosoundonlysilnclayorthfildsandwoodsandmarshOnthfarmsthhnsbroodd,butnochickshatchdThfarmrscomplaindthatthywrunabltoraisanypigsmdashthlittrswrsmallandthyoungsuridonlyafwdaysThappltrswrcomingintobloombutnobsdrondamongthblossoms,sothrwasnopollinationandthrwouldbnofruitThroadsids,oncsoattracti,wrnowlindwithbrowndandwithrdgtationasthoughswptbyfirThs,too,wrsilnt,dsrtdbyallliingthingsEnthstramswrnowliflssAnglrsnolongrisitdthm,forallthfishhaddidInthguttrsundrthasandbtwnthshinglsofthroofs,awhitgranularpowdrstillshowdafwpatchssomwksbforithadfallnliksnowuponthroofsandthlawns,thfildsandstramsNowitchcraft,nonmyactionhadsilncdthrbirthofnwlifinthisstricknworldThpoplhaddonitthmslsThistowndosnotactuallyxist,butitmightasilyhaathousandcountrpartsinAmricaorlswhrinthworldIknowofnocommunitythathasxprincdallthmisfortunsIdscribYtryonofthsdisastrshasactuallyhappndsomwhr,andmanyralcommunitishaalradysuffrdasubstantialnumbrofthmAgrimspctrhascrptuponusalmostunnoticd,andthisimagindtragdymayasilybcomastarkralitywallshallknowWhathasalradysilncdthoicsofspringincountlsstownsinAmricaThisbookisanattmpttoxplainThObligationtoEndurTHEHISTORYOFLIFEonarthhasbnahistoryofintractionbtwnliingthingsandthirsurroundingsToalargxtnt,thphysicalformandthhabitsoftharthrsquosgtationanditsanimallifhabnmolddbythnironmntC<spanclass='wran'>ons<span>idringthwholspanofarthlytim,thoppositffct,inwhichlifactuallymodifisitssurroundings,hasbnrlatilyslightOnlywithinthmomntoftimrprsntdbythprsntcnturyhas<spanclass='wran'>ons<span>pcismdashmanmdashacquirdsignificantpowrtoaltrthnaturofhisworldDuringthpastquartrcnturythispowrhasnotonlyincrasdtoonofdisturbingmagnitudbutithaschangdincharactrThmostalarmingofallmanrsquosassaultsuponthnironmntisthcontaminationofair,arth,rirs,andsawithdangrousandnlthalmatrialsThispollutionisforthmostpartirrcorablthchainofilitinitiatsnotonlyinthworldthatmustsupportlifbutinliingtissusisforthmostpartirrrsiblInthisnowunirsalcontaminationofthnironmnt,chmicalsarthsinistrandlittlrcognizdpartnrsofradiationinchangingthrynaturofthworldmdashthrynaturofitslifStrontium,rlasdthroughnuclarxplosi<spanclass='wran'>ons<span>intothair,comstoarthinrainordriftsdownasfallout,lodgsinsoil,ntrsintothgrassorcornorwhatgrownthr,andintimtaksupitsabodinthb<spanclass='wran'>ons<span>ofahumanbing,thrtormainuntilhisdathSimilarly,chmicalsspraydoncroplandsorforstsorgardnslilonginsoil,ntringintoliingorganisms,passingfromontoanothrinachainofpoisoninganddathOrthypassmystriouslybyundrgroundstramsuntilthymrgand,throughthalchmyofairandsunlight,combinintonwformsthatkillgtation,sickncattl,andworkunknownharmonthoswhodrinkfromoncpurwllsAsAlbrtSchwitzrhassaid,lsquoMancanhardlynrcognizthdilsofhisowncrationrsquoIttookhundrdsofmilli<spanclass='wran'>ons<span>ofyarstoproducthlifthatnowinhabitstharthmdash<spanclass='wran'>ons<span>oftiminwhichthatdlopingandolinganddirsifyinglifrachdastatofadjustmntandbalancwithitssurroundingsThnironmnt,rigorouslyshapinganddirctingthlifitsupportd,containdlmntsthatwrhostilaswllassupportingCrtainrocksgaoutdangrousradiationnwithinthlightofthsun,fromwhichalllifdrawsitsnrgy,thrwrshortwaradiati<spanclass='wran'>ons<span>withpowrtoinjurGintimmdashtimnotinyarsbutinmillnniamdashlifadjusts,andabalanchasbnrachdFortimisthssntialingrdintbutinthmodrnworldthrisnotimThrapidityofchangandthspdwithwhichnwsituati<spanclass='wran'>ons<span>arcratdfollowthimptuousandhdlsspacofmanrathrthanthdlibratpacofnaturRadiationisnolongrmrlythbackgroundradiationofrocks,thbombardmntofcosmicrays,thultraioltofthsunthathaxistdbforthrwasanylifonarthradiationisnowthunnaturalcrationofmanrsquostampringwiththatomThchmicalstowhichlifisaskdtomakitsadjustmntarnolongrmrlythcalciumandsilicaandcopprandallthrstofthminralswashdoutofthrocksandcarridinrirstothsathyarthsynthticcrati<spanclass='wran'>ons<span>ofmanrsquosinntimind,brwdinhislaboratoris,andhaingnocountrpartsinnaturToadjusttothschmicalswouldrquirtimonthscalthatisnaturrsquositwouldrquirnotmrlythyarsofamanrsquoslifbutthlifofgnrati<spanclass='wran'>ons<span>Andnthis,writbysommiraclpossibl,wouldbfutil,forthnwchmicalscomfromourlaboratorisinanndlssstramalmostfihundrdannuallyfindthirwayintoactualusinthUnitdStatsalonThfigurisstaggringanditsimplicati<spanclass='wran'>ons<span>arnotasilygraspdmdashnwchmicalstowhichthbodisofmnandanimalsarrquirdsomhowtoadaptachyar,chmicalstotallyoutsidthlimitsofbiologicxprincAmongthmarmanythatarusdinmanrsquoswaragainstnaturSincthmidsorbasicchmicalshabncratdforusinkillinginscts,wds,rodnts,andothrorganismsdscribdinthmodrnrnacularaslsquopstsrsquoandthyarsoldundrsralthousanddiffrntbrandnamsThssprays,dusts,andarosolsarnowapplidalmostunirsallytofarms,gardns,forsts,andhomsmdashn<spanclass='wran'>ons<span>lctichmicalsthathathpowrtokillryinsct,thlsquogoodrsquoandthlsquobadrsquo,tostillthsongofbirdsandthlapingoffishinthstrams,tocoatthlaswithadadlyfilm,andtolingroninsoilmdashallthisthoughthintnddtargtmaybonlyafwwdsorinsctsCananyonbliitispossibltolaydownsuchabarragofpois<spanclass='wran'>ons<span>onthsurfacoftharthwithoutmakingitunfitforalllifThyshouldnotbcalldlsquoinscticidsrsquo,butlsquobiocidsrsquoThwholprocssofsprayingsmscaughtupinanndlssspiralSincDDTwasrlasdforciilianus,aprocssofscalationhasbngoingoninwhichrmortoxicmatrialsmustbfoundThishashappndbcausinscts,inatriumphantindicationofDarwinrsquosprinciplofthsurialofthfittst,haoldsuprracsimmuntothparticularinscticidusd,hncadadlironhasalwaystobdlopdmdashandthnadadlironthanthatIthashappndalsobcaus,forras<spanclass='wran'>ons<span>tobdscribdlatr,dstructiinsctsoftnundrgoalsquoflarbackrsquo,orrsurgnc,aftrspraying,innumbrsgratrthanbforThusthchmicalwarisnrwon,andalllifiscaughtinitsiolntcrossfirAlongwiththpossibilityofthxtinctionofmankindbynuclarwar,thcntralproblmofouraghasthrforbcomthcontaminationofmanrsquostotalnironmntwithsuchsubstancsofincrdiblpotntialforharmmdashsubstancsthataccumulatinthtissusofplantsandanimalsandnpntratthgrmcllstoshattroraltrthrymatrialofhrdityuponwhichthshapofthfuturdpndsSomwouldbarchitctsofourfuturlooktowardatimwhnitwillbpossibltoaltrthhumangrmplasmbydsignButwmayasilybdoingsonowbyinadrtnc,formanychmicals,likradiation,bringaboutgnmutati<spanclass='wran'>ons<span>ItisironictothinkthatmanmightdtrminhisownfuturbysomthingsosminglytriialasthchoicofaninsctsprayAllthishasbnriskdmdashforwhatFuturhistoriansmaywllbamazdbyourdistortdsnsofproportionHowcouldintlligntbingssktocontrolafwunwantdspcisbyamthodthatcontaminatdthntirnironmntandbroughtththratofdisasanddathntothirownkindYtthisisprcislywhatwhadonWhadonit,moror,forras<spanclass='wran'>ons<span>thatcollapsthmomntwxaminthmWartoldthatthnormousandxpandingusofpsticidsisncssarytomaintainfarmproductionYtisourralproblmnotonoforproductionOurfarms,dspitmasurstormoacragsfromproductionandtopayfarmrsnottoproduc,hayilddsuchastaggringxcssofcropsthatthAmricantaxpayrinispayingoutmorthanonbilliondollarsayarasthtotalcarryingcostofthsurplusfoodstoragprogramAndisthsituationhlpdwhnonbranchofthAgriculturDpartmnttristorducproductionwhilanothrstats,asitdidin,lsquoItisblidgnrallythatrductionofcropacragsundrproisi<spanclass='wran'>ons<span>ofthSoilBankwillstimulatintrstinusofchmicalstoobtainmaximumproductiononthlandrtaindincropsrsquoAllthisisnottosaythrisnoinsctproblmandnondofcontrolIamsaying,rathr,thatcontrolmustbgardtoralitis,nottomythicalsituati<spanclass='wran'>ons<span>,andthatthmthodsmploydmustbsuchthatthydonotdstroyusalongwiththinsctsThproblmwhosattmptdsolutionhasbroughtsuchatrainofdisastrinitswakisanaccompanimntofourmodrnwayoflifLongbforthagofman,insctsinhabitdtharthmdashagroupofxtraordinarilyaridandadaptablbingsOrthcoursoftimsincmanrsquosadnt,asmallprcntagofthmorthanhalfamilli<spanclass='wran'>ons<span>pcisofinsctshacomintoconflictwithhumanwlfarintwoprincipalways:ascomptitorsforthfoodsupplyandascarrirsofhumandisasDisascarryinginsctsbcomimportantwhrhumanbingsarcrowddtogthr,spciallyundrconditi<spanclass='wran'>ons<span>whrsanitationispoor,asintimofnaturaldisastrorwarorinsituati<spanclass='wran'>ons<span>ofxtrmportyanddpriationThncontrolofsomsortbcomsncssaryItisasobringfact,howr,aswshallprsntlys,thatthmthodofmassichmicalcontrolhashadonlylimitdsuccss,andalsothratnstoworsnthryconditi<spanclass='wran'>ons<span>itisintnddtocurbUndrprimitiagriculturalconditi<spanclass='wran'>ons<span>thfarmrhadfwinsctproblmsThsaroswiththintnsificationofagriculturmdashthdotionofimmnsacragstoasinglcropSuchasystmstthstagforxplosiincrassinspcificinsctpopulati<spanclass='wran'>ons<span>SinglcropfarmingdosnottakadantagofthprinciplsbywhichnaturworksitisagriculturasannginrmightconciittobNaturhasintroducdgratarityintothlandscap,butmanhasdisplaydapassionforsimplifyingitThushundosthbuiltinchcksandbalancsbywhichnaturholdsthspciswithinboundsOnimportantnaturalchckisalimitonthamountofsuitablhabitatforachspcisObiouslythn,aninsctthatlisonwhatcanbuildupitspopulationtomuchhighrllsonafarmdotdtowhatthanononinwhichwhatisintrmingldwithothrcropstowhichthinsctisnotadaptdThsamthinghappnsinothrsituati<spanclass='wran'>ons<span>Agnrationormorago,thtownsoflargarasofthUnitdStatslindthirstrtswiththnobllmtrNowthbautythyhopfullycratdisthratndwithcompltdstructionasdisasswpsthroughthlms,carridbyabtlthatwouldhaonlylimitdchanctobuilduplargpopulati<spanclass='wran'>ons<span>andtospradfromtrtotrifthlmswronlyoccasionaltrsinarichlydirsifidplantingAnothrfactorinthmodrninsctproblmisonthatmustbiwdagainstabackgroundofgologicandhumanhistory:thspradingofthousandsofdiffrntkindsoforganismsfromthirnatihomstoinadnwtrritorisThisworldwidmigrationhasbnstudidandgraphicallydscribdbythBritishcologistCharlsEltoninhisrcntbookThEcologyofInasi<spanclass='wran'>ons<span>DuringthCrtacousPriod,somhundrdmillionyarsago,floodingsascutmanylandbridgsbtwncontinntsandliingthingsfoundthmslsconfindinwhatEltoncallslsquocolossalsparatnaturrsrsrsquoThr,isolatdfromothrsofthirkind,thydlopdmanynwspcisWhnsomofthlandmassswrjoindagain,aboutmillionyarsago,thsspcisbgantomooutintonwtrritorismdashamomntthatisnotonlystillinprogrssbutisnowrciingc<spanclass='wran'>ons<span>idrablassistancfrommanThimportationofplantsisthprimaryagntinthmodrnspradofspcis,foranimalshaalmostinariablygonalongwiththplants,quarantinbingacomparatilyrcntandnotcompltlyffctiinnoationThUnitdStatsOfficofPlantIntroductionalonhasintroducdalmost,spcisandaritisofplantsfromallorthworldNarlyhalfofthorsomajorinsctnmisofplantsinthUnitdStatsaraccidntalimportsfromabroad,andmostofthmhacomashitchhikrsonplantsInnwtrritory,outofrachofthrstraininghandofthnaturalnmisthatkptdownitsnumbrsinitsnatiland,aninadingplantoranimalisabltobcomnormouslyabundantThusitisnoaccidntthatourmosttroublsominsctsarintroducdspcisThsinasi<spanclass='wran'>ons<span>,boththnaturallyoccurringandthosdpndntonhumanassistanc,arliklytocontinuindfinitlyQuarantinandmassichmicalcampaignsaronlyxtrmlyxpnsiwaysofbuyingtimWarfacd,accordingtoDrElton,lsquowithalifanddathndnotjusttofindnwtchnologicalmansofsupprssingthisplantorthatanimalrsquoinstadwndthbasicknowldgofanimalpopulati<spanclass='wran'>ons<span>andthirrlati<spanclass='wran'>ons<span>tothirsurroundingsthatwilllsquopromotannbalancanddampdownthxplosipowrofoutbraksandnwinasi<spanclass='wran'>ons<span>rsquoMuchofthncssaryknowldgisnowaailablbutwdonotusitWtraincologistsinourunirsitisandnmploythminourgornmntalagncisbutwsldomtakthiradicWallowthchmicaldathraintofallasthoughthrwrnoaltrnati,whrasinfactthrarmany,andouringnuitycouldsoondiscormanymorifginopportunityHawfallnintoamsmrizdstatthatmaksusaccptasinitablthatwhichisinfriorordtrimntal,asthoughhainglostthwillorthisiontodmandthatwhichisgoodSuchthinking,inthwordsofthcologistPaulShpard,lsquoidalizslifwithonlyitshadoutofwatr,inchsabothlimitsoftolrationofthcorruptionofitsown
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