雅思阅读(达尔文).docx

Darwin’sTheoryofEvolution
MosteducatedpeopleinEuropeandtheAmericasduringthe19thcenturyhadtheirfirstfullexposure（暴露、公开）totheconceptofevolutionthroughthewritingsofCharlesDarwin.Clearly,Darwindidnotinvent（发明、创造）theideawhichhadhappenedlongbeforehewasborn.However,hecarriedoutthenecessaryresearchtoconclusively（令人信服的，确凿的）documentthatevolutionhasoccurredandthenmadetheideaacceptableforscientistsandthegeneralpublic.Thiswasnoteasysincetheideaofevolutionhadbeenstronglyassociatedwithradical（根本的，基本的）scientificandpoliticalviewscomingoutofpost-revolutionaryFranceandhencewaswidelyconsideredtobeathreattotheestablishedsocialandpoliticalorder.
Darwinwasinfluencedbyobservationsmadeduringhisyouthfulvoyage（旅行，航海，远行，旅程）asnaturalist（自然主义者）onthesurveyshipBeagle.OntheGalapagosIslands（加拉帕戈斯群岛）henoticedtheslightvariations（变化）thatmadetortoisesfromdifferentislandsrecognizably（可被认识地，可辨别地）distinct.Healsoobservedawholearrayofuniquefinches（雀科鸣鸟）,thefamous“Darwin’sfinches”（达尔文地雀）,thatexhibited（陈列，展览，表现，显示）slightdifferencesfromislandtoisland.Inaddition,theyallappearedtoresemble（与…相像，类似于）,butdifferfrom,thecommonfinchonthemainland（大陆，本土）ofEcuador（厄瓜多尔）,600milestotheeast.Patternsinthedistributionandsimilarityoforganisms（有机物，有机体，生物）hadanimportantinfluenceofDarwin’sthinking.
Darwin’stheoryofevolutionentails（牵涉，需要，使必要）thefollowingfundamentalideas.Firstly,specieschangeovertimeandspace.Therepresentatives（代表）ofspecieslivingtodaydifferfromthosethatlivedintherecentpast,andpopulationsindifferentgeographicregionstodaydifferslightlyinformorbehavior.Secondly,allorganismssharecommonancestors（祖先）withotherorganisms.Overtime（随着时间的过去）,populationsmaydiverge（分开、偏离）intodifferentspecieswhichshareacommonancestral（祖先的）population.Thismeansfarenoughbackintime（足够早的时间）,anypairoforganismssharesacommonancestor.Forexample,humanssharedacommonancestorwithchimpanzeesabouteightmillionyearsago,withwhalesabout60millionyearsago,andwithkangaroos（袋鼠）over100millionyearsago.Thirdly,evolutionarychangeisgradualandslowinDarwin’sview.Thisclaim（要求，声称