北師大版2023 選擇性必修第一冊 Unit 3 Conservation Lesson 1 The Sixth Extinction課件(共24張PPT)

第第頁北師大版（2023）選擇性必修第一冊Unit3ConservationLesson1TheSixthExtinction課件(共24張PPT)(共24張PPT)

新北師大版高中英語選擇性必修一Unit3Conservation

Lesson1TheSixExtinction

Dodo(渡渡鳥),extinctflightlessbirdofMauritius(anislandoftheIndianOcean).ItwasfirstseenbyPortuguesesailorsin1507andexterminatedbyhumansandtheirintroducedanimals.Thedodowasextinctin1680.

WarmingUp

Passengerpigeon(北美候鴿),migratorybirdhuntedtoextinctionbyhumans.From1870thedeclineofthespeciesbecameprecipitous,anditwasofficiallyclassifiedasextinctwhenthelastknownrepresentativediedonSeptember1,1914intheCincinnati(Ohio)Zoo.

WarmingUp

Hawaianchaffflower(夏威夷牛膝草)waseverywhereonthebeachesofHawaiiinthe1950sand1960s.Unfortunately,Hawaiihasbecomeapopulardestination.Theshrubbyplant'shabitathasbeenerodedbyhotels,apartmentsandtouristdevelopments,leavingitextinctinashortperiodoftime(extinctin1990).

WarmingUp

Pyreneanibex(比利牛斯山羊),oncecommonlyfoundinSouthernFrance,NorthernPyreneesandCantabrianMountains,wasoneofthefoursubspeciesofIberianwildgoatorSpanishibex.Theywerefoundinhugenumbersevenafewhundredyearsago.However,by1900thenumberswentdowntoless

than100,andafter1910,

thenumberneverwentup

above40.ThelastPyrenean

ibexwasCelia,afemale,

founddeadintheyear2000.

WarmingUp

Extinctionofspecies

extinction:asituationinwhichsomethingnolongerexists

species:asetofanimalsorplantsinwhichmembershavesimilarcharacteristicstoeachother

1

HowmuchdoyouknowaboutextinctionChoosetheoptionbasedonyourknowledge.

1.HowmanytimesuptotodayhaslifeonEarthalmostdiedout

a.Onceb.Fivetimes

c.Morethan10times

2.AboutwhatpercentofallspeciesonEarthbecameextinctduringthemassextinctionknownasthe“GreatDying”

a.Lessthan10%b.Nearly50%

c.Morethan90%

DoyouknowanyotherextinctanimalsShareinclass.

3.Whatdoscientiststhinkwillcausethenextmassextinction

a.Humanactivity

b.Naturalcauses

c.Unknownreasons

Extinction:whenaparticulartypeofanimalorplantstopsexisting.(LongmanDictionary5thEdition)

FivetimesofextinctionReasons

1st:439millionyearsago,86%oflifeonEarthwaswipedout

2nd:364millionyearsago,75%ofspecieswerelost

3rd:251millionyearsago,96%ofspecieswerelost

4th:199-214millionyearsago,manyspecieswerelost

5th:65millionyearsago,ended76%oflifeonearth,theextinctionofdinosaurs

Activateandshare

Readthefirstparagraphandunderlinethereasonsforthefivetimesofextinction.

Readthetextaboutextinctionandfindthemainideaforeachparagraph.

ReadandExplore

acauses/reasons

bwhatmighthappen

cwhatwecando

dbackgroundhistory

Para.1

Para.2

Para.3

Para.4

2.Readandexplore.

Readatextaboutextinction.ThencheckyouranswersinActivity1.

①Extinctions,whereentirespeciesarewipedout,arenotunusualinourEarth’shistory.Infact,over90percentofallspeciesthateverlivedarenowextinct.Inthelast500millionyears,therehavebeenfivetimeswhenlifeonEarthhasalmostended.Theseincludethethirdmassextinction,knownasthe“GreatDying”,whichkilled90%to96%ofallspecies.Andthefifthevent,whichoccurred66millionyearsago,causedthedeathofthedinosaurs.Thereasonsforextinctionsarevaried.Accordingtoscientists,theyincludevolcaniceruptions,asteroidshittingtheEarthfromspace,changesinsealevels,thedecreaseoftheoxygencontentoftheseaandglobalwarming.ManyscientistssaywearenowenteringtheEarth’ssixthmassextinction.Thistime,humanactivitywillbetoblame.

非限制性定語從句

限制性定語從句

限制性定語從句

非限制性定語從句

非限制性定語從句

承上啟下

②Althoughitisnotunusualforspeciestodieoutnaturally,therateatwhichthisisnowhappeningiscauseforconcern.A2023studybyscientistswhowerebasedatBrownUniversityandDukeUniversityintheUS,lookedathowquicklyspeciesdieoutduetonaturalcauses,thatis,the“backgroundextinctionrate”.Theyfoundthathumanactivityiscausingspeciestodieout1,000timesfasterthannormal.Thereisalonglistofreasonswhysomanyspeciesaredyingout:airandwaterpollution,forestsbeingdestroyed,factoryfarmingandoverfishing.ItisclearthathumanactivityhasnegativelyaffectedallotherspeciesonEarth,includinganimalsandplants.

雙重否定,表示肯定

Itisadjforsb/sthtodosth

做...對某人/某物來說...

限制性定語從句

限制性定語從句

賓語從句

Itisadjthat...

...是怎么樣的

Ifasixthmassextinctionoccurs,scientistswhohavestudiedtheissuebelievethatuptothreequartersofallspeciesonEarthcoulddieout.Ofcourse,aswehumansdependonsomanyspeciesforoursurvival,wewouldalsobeatriskofdyingout.Ourworldandourlivesdependonthebalanceinnaturebetweenanimalsandplants.Withoutforests,wewouldhavenoairtobreathe,andwithoutcleanwaterwewouldbeunabletosurvive.

限制性定語從句

賓語從句

因為

thenbetweenAandB

A和B之間的...

例：thecompetitionbetweenAandB

A和B之間的競爭

CanasixthextinctionbeavoidedExpertssaythatitisnotyettoolate,ifwetakeactionnow.Thiswouldmeanwehavetosignificantlychangethewaywelive.Forexample,weneedtotakestepstosaveendangeredspecies,includingsettingupspecialareaswhereplantsandanimalscanbeprotected.Weneedtochangehowweworkandtravelbyusingcleaner,morenaturalsourcesofenergy,suchaswindandsolarenergy.Wealsoneedtoimproveourfarmingmethodstoreducewater,airandlandpollution.Inshort,ifwewanttosurvive,weneedtostopdestroyingtheplanetthatweliveonandstarttoprotectit.

bedone(動詞的過去分詞)被動語態(tài)

限制性定語從句

Forinstance

表目的

表條件

TheBlackRobin

Blackrobinsarethebirdsthathumanssavedfromextinction.In1980,therewereonlyfiveblackrobinsleftintheworld.TheyalllivedonasmallislandoffthecoastofNewZealand.Onlyoneofthosebirds,afemalecalledOldBlue,wasabletolayeggs.Wildlifeworkersbeganaprogrammeforraisingblackrobinchicks.TheyprotectedOldBlue’seggs,helpedthemtohatch,andtookcareofthechicks.（幼鳥）Thankstotheirefforts,therearenowmorethan250blackrobins,andthepopulation（數(shù)量）isspreading.Tohelpthemsurvive,peoplearerestoringtheirhabitatsandremovingsmallanimalsthathuntthem,suchasmiceandcatsfromtheislandswheretheylive.

CaseStudy

robinn.知更鳥

habitatn.棲息地

限制性定語從句

定語

多虧，由于

限制性定語從句

WillHumansSurvivetheSixthGreatExtinction

SupposeyouareamemberofGreenClubinyourschool.Prepareaspeechentitled“WillHumansSurvivetheSixthGreatExtinction”Trytoexplainthesixthmassextinction,analyzeitscausesandeffects,andoffersolutionsinyourspeech.

Expressyourself

Readthetextandusethegraphicorganizertoshowthedetailedinformationaboutthesixthextinction.

ReadandExplore

Inthelast500millionyears,therehavebeenfivemassextinctioneventsonEarth.Inthethirdevent,which1.__________the“GreatDying”,90%to96%ofallspecies2._________.Ofcourse,speciesdiedoutduetomanycauses.Butnowadays,humanactivity3.___________alltypesofspeciesthatwe4.___________forliving.Weneedto5.___________toavoidthesixthmassextinction.Weshould6.__________tosaveendangeredanimalsandplants,and7._______specialareasto8.___________thembeforethenextextinctioncomesthatmay9._________theentirespecies.

Completetheparagraphaboutextinctionsusingthecorrectformofthephrasesbelow.

isknownas

diedout

hasaffected

dependon

takeaction

takesteps

setup

takecareof

wipeout

dieoutbeknownashaveaffecteddependonwipeout

takestepstakeactionsetuptakecareof

Summary

Asateenager,whatcouldwe