专题八科普知识型阅读理解专题八科普知识型阅读理解专题导读专题八│专题导读科普类文章是高考阅读理解中的难点题材，其取材密切联系当前经济和科技等方面的变化，以介绍某一科学现象居多。科普类文章具有结构严谨、逻辑性强等特点。其主要命题形式有事实细节题、词义猜测题、推理判断题以及主旨概括题等，其中推理判断题居多。这类文章的总体特点是：科技词汇多，句子结构复杂，理论性强，逻辑严谨。具体说来它有以下特点：专题导读专题八│专题导读1．文章中词汇的意义比较单一、稳定、简明，不带感情色彩，具有单一性和准确性的特点。这类文章通常不会出现文学英语中常用的排比、比喻、夸张等修辞手法，一词多义的现象也不多见。2．句子结构较复杂，语法分析较困难。为了描述一个客观事物，严密地表达自己的思想，作者经常会使用集多种语法现象于一体的长句。3．常使用被动语态，尤其是一些惯用被动句式。真题典例专题八│真题典例【2011·湖南卷】ArecentstudyofancientandmodernelephantshascomeupwiththeunexpectedconclusionthattheAfricanelephantisdividedintotwodistinct(不同的)species.ThediscoverywasmadebyresearchersatYorkandHarvardUniversitieswhentheywereexaminingthegeneticrelationshipbetweentheancientwoollymammothandmastodontomodernelephants—theAsianelephant，Africanforestelephant，andAfricansavannaelephant.OncetheyobtainedDNAsequences(序列)fromtwofossils(化石)，mammothsandmastodons，theteam专题八│真题典例comparedthemwithDNAfrommodernelephants.TheyfoundtotheiramazementthatmodernforestandsavannaelephantsareasdistinctfromeachotherasAsianelephantsandmammoths.ThescientistsuseddetailedgeneticanalysistoprovethattheAfricansavannaelephantandtheAfricanforestelephanthavebeendistinctspeciesforseveralmillionyears.ThedivergenceofthetwospeciestookplacearoundthetimeofthedivergenceofAsianelephantsandwoollymammoths.Thisresultamazedallthescientists.Therehaslongbeendebateinthescientificcommunitythatthetwomightbeseparatespecies，butthisisthemostconvincingscientificevidencesofarthattheyareindeeddifferentspecies.专题八│真题典例Previously，manynaturalistsbelievedthatAfricansavannaelephantsandAfricanforestelephantsweretwopopulationsofthesamespecies，despitetheelephants’significantsizedifferences.Thesavannaelephanthasanaverageshoulderheightof3.5metreswhiletheforestelephanthasanaverageshoulderheightof2.5metres.Thesavannaelephantweighsbetweensixandseventons，roughlydoubletheweightoftheforestelephant.Butthefactthattheylooksodifferentdoesnotnecessarilymeantheyaredifferentspecies.HowevertheprooflayintheanalysisoftheDNA.AlfredRoca，assistantprofessorintheDepartmentofAnimalSciencesattheUniversityofIllinois，said，“We专题八│真题典例nowhavetotreattheforestandsavannaelephantsastwodifferentunitsforconservationpurposes.Since1950，allAfricanelephantshavebeenconservedasonespecies.Nowthatweknowtheforestandsavannaelephantsaretwoverydistinctiveanimals，theforestelephantshouldbecomeabiggerpriority(优先)forconservationpurposes.”()1.Oneofthefossilsstudiedbytheresearchersisthatof________.A．theAsianelephantB．theforestelephantC．thesavannaelephantD．themastodonelephant专题八│真题典例()2.Theunderlinedword“divergence”inparagraph4means“________.”A．evolutionB．exhibitionC．separationD．examination()3.Theresearchers’conclusionwasbasedonastudyoftheAfricanelephant’s________.A．DNAB．heightC．weightD．population专题八│真题典例()4.WhatareAlfredRoca’swordsmainlyabout?A．TheconservationofAfricanelephants.B．ThepurposeofstudyingAfricanelephants.C．ThewaytodivideAfricanelephantsi...
