Becauseplantscannotmoveortalk,mostpeoplebelievethattheyhavenofeelingsandthattheycannotreceivesignalsfromoutside.However,thismaynotbecompletelytrue. Peoplewhostudiedplantshavefoundoutthatplantscarryasmallelectricalcharge(电荷).Itispossibletomeasurethischargewithasmallpieceofequipmentcalled“galvanometer”.Thegalvanometerisplacedonaleafofftheplant,anditrecordsanychangesintheelectricalfieldoftheleaf.Humanshaveasimilarfieldwhichcanchangewhenweareshockedorfrightened. AmancalledBacksterusedagalvanometerforhisstudiesofplantsandwasverysurprisedathisresults.Hefoundthatifhehadtwoormoreplantsinaroomandhebegantodestroyoneofthem-perhapsbypullingoffitsleavesorbypullingitoutofitspot-thenthegalvanometerontheleavesoftheotherplantsshowedachangeintheelectricalfield.Itseemedasiftheplantsweresignallingafeelingofshock.ThishappenednotonlywhenBacksterstartedtodestroyplants,butalsowhenhedestroyedotherlivingthingssuchasinsects(昆虫). Backstersaidthattheplantsalsoknewifsomeonehaddestroyedalivingthingsomedistanceaway,becausetheysignalledwhenamanwhohadjustcutdownatreeenteredtheroom. Anotherscientist,namedSauvin,achievedsimilarresultstoBackster’s.Hekeptgalvanometersfixedtohisplantsallthetimeandcheckedregularlytoseewhattheplantsweredoing.Ifhewasoutoftheoffice,hetelephonedtofindoutaboutthesignalstheplantsweresending.Inthisway,hefoundthattheplantsweresendingoutsignalsattheexacttimeswhenhefeltstrongpleasureorpain.Infact,Sauvincouldcauseachangeintheelectricalfieldofhisplantsoveradistanceofafewmilessimplybythinkingaboutthem. 小题1:Backsterwassurprisedattheresultsofhisstudiesbecause_____. |