国际交流英语视听说B2U7

国际交流英语视听说国际交流英语视听说Unit7SpeciesSurvivalBook2国际交流英语视听说国际交流英语视听说Think and DiscussViewing the WorldExploring the ThemeAnalytical ListeningSharing Your IdeasEngagingFurther ListeningContentContent国际交流英语视听说Unit7SpeciesSurvivalThinkandDiscussThinkandDiscussThinkandDiscuss1.Lookatthephotoandreadtheinformationonthispage.Whattopicsdoyouthinkyouwilldiscussinthisunit?2.Overtime,giraffeshavedevelopedverylongnecks.Whydoyouthinkthishappened?Howarelongneckshelpfultogiraffes?GiraffesinSouthAfricaQuestionsQuestionsThinkandDiscussExampleAnswersWewillprobablydiscussdifferentspeciesofanimalsandhowthoseanimalssurvive.QuestionsQuestions1.Lookatthephotoandreadtheinformationonthispage.Whattopicsdoyouthinkyouwilldiscussinthisunit?ThinkandDiscussQuestionsQuestions2.Overtime,giraffeshavedevelopedverylongnecks.Whydoyouthinkthishappened?Howarelongneckshelpfultogiraffes?ExampleAnswersGiraffesprobablydevelopedlongnecksthroughtheprocessofnaturalselection.Forthem,longneckswereanadvantage.Individualgiraffeswithlongernecksthanothergiraffescouldreachandeatmoretreeleaves,andsurvivetohavemorebabiesthanothergiraffes.Thebabies,ofcourse,werelikelytoalsohavelongernecks.国际交流英语视听说ExploringtheThemeExploringtheThemeUnit7SpeciesSurvivalExploringtheThemeSpeciesSurvivalCharlesDarwin(1809–1882):aBritishscientist.HeisrememberedforthepromotionofthetheoryofevolutioninhisbookOntheOriginofSpeciesbyMeansofNaturalSelection.查尔斯·达尔文ExploringtheThemeSpeciesSurvivalCongoBasin:alargebasininAfrica.Itisthedrainage(排水)basinoftheCongoRiver.Theregionishometolargeareasoftropicalrainforestandwetlands.刚果盆地ExploringtheThemeLookatthephotosandreadthecaptions.Thendiscussthequestions.1.WhatdidDarwindointheGalápagos?Whatishistheorycalled?2.Whataretwoexamplesofusefultraitsthathelpanimalssurvive?3.Whatarescientistsdoingtohelpspeciessurvive?SpeciesSurvivalExploringtheThemeSullivanBay,BartolomeIsland,GalápagosIslandsSpeciesSurvivalExploringtheThemeTheGalápagosIslandsandNaturalSelectionCharlesDarwin,anEnglishnaturalist,visitedtheGalápagosIslandswherehestudiedmanyinterestingspeciesofanimalsanddevelopedhistheorycalled“naturalselection”.Accordingtohistheory,animalsofthesamespecieshaveslightlydifferenttraits.Animalsthathavehelpfultraitsaremorelikelytosurviveandreproduce.Theoffspringoftheseanimalsinheritthehelpfultraitsfromtheirparents,andovertime,allofthemembersofaspecieshavethishelpfultrait.SpeciesSurvivalExploringtheThemeDarwinstudiedhowsmalldifferencesincertaintraitswithineachspeciesofanimalcouldbehelpfulforitssurvival.Forexample,theshellsofthegianttortoisesintheGalápagosweredifferentsizesandshapesdependingonwhichislandtheylivedonandwhattheyate.HowNatureandScienceHelpSpeciesSurviveSpeciesSurvivalExploringtheThemeOvertimetheArcticharehasdevelopedaveryusefultrait—athickwhitecoat,whichkeepsitwarminthewinter.Thehare’swhitecoatalsomakesitdifficultforitspredatorstoseeitagainstthesnowandice.HowNatureandScienceHelpSpeciesSurviveSpeciesSurvivalExploringtheThemeScientistsandresearchersaretravelingtoplacesliketheCongoBasininAfricaandmakingnotesandkeepingtrackofallofthedifferentspeciestheyfind.Theyaredoingthisinordertohelppreventthespeciestherefrombecomingextinct.HowNatureandScienceHelpSpeciesSurviveSpeciesSurvivalExploringtheThemeAnswerKeysIntheGalápagosIslands,CharlesDarwinstudiedtheanimalsthatlivedthereandobservedsmallvariationsinthespecies.HelaterdevelopedhistheoryofnaturalselectionusinghisdatafromtheGalápagos.SpeciesSurvival1.WhatdidDarwindointheGalápagos?Whatishistheorycalled?ExploringtheThemeAnswerKeysThefirstexampleistheshellsofthegianttortoisesintheGalápagos.Theshellsaredifferentsizesandshapesdependingonwhichislandtheyliveonandwhattheyeat.ThesecondexampleisthethickwhitecoatoftheArctichare.Thehare’scoatkeepsitwarminthewinterandalsomakesitdifficultforitspredatorstoseeitagainstthesnowandice.SpeciesSurvival2.Whataretwoexamplesofusefultraitsthathelpanimalssurvive?ExploringtheThemeAnswerKeysScientistsaretravelingtoplacesliketheCongoBasinandcreatingrecordsofallthespeciesfoundinthoseareas.Theyhopethiswillhelptopreventtheextinctionofcertainspecies.SpeciesSurvival3.Whatarescientistsdoingtohelpspeciessurvive?国际交流英语视听说AnalyticalListeningAnalyticalListeningUnit7SpeciesSurvivalAnalyticalListeningprehistorica.史前的，有历史记载以前的diversityn.（人或事物的）多样性，多元化finchn.雀科鸣禽goldfinchn.黄雀；红额金翅雀beakn.鸟嘴，喙greenfinchn.金翅Listening1AnalyticalListeningtheBeaglevoyage:aseavoyageontheshipH.M.S.Beagle.Theship’smainjobwastomapthecoastandharborsofSouthAmericafortwoyears,butitsvoyagelastedforfiveyears.CharlesDarwinjoinedtheexpeditionmainlyasacompanionfortheship’scaptain,butitistheresultsofDarwin’sworkthathavemadetheshipfamous.比格尔航行Listening1AnalyticalListeningListening1Anadultfinch(withredbeak)teachesitssongstoachick(雏鸟).Thechickhasagenethatmakesitabletolearnsinging.AnalyticalListeningBeforeListeningListening1Whenwetakenoteswhilewearelistening,weoftenhavetowritedownimportantinformationquickly.Herearesomenote-takingstrategieswecanusetohelpusdothis.•Writeonlykeywords.Listenforthecontentwords(nouns,verbs,adjectives,andadverbs)thatwillbestr