Unit 3 Lesson 1 The Sixth Extinction（ppt课件） -2023新北师大版（2019）《高中英语》选择性必修第一册.pptx

1、新北师大版高中英语选择性必修一新北师大版高中英语选择性必修一Unit3 ConservationLesson1 The Six ExtinctionDodo(渡渡鸟),extinct flightless bird of Mauritius(an island of the Indian Ocean).It was first seen by Portuguese sailors in 1507 and exterminated by humans and their introduced animals.The dodo was extinct in 1680.Warming UpPasse

2、nger pigeon(北美候鸽),migratory bird hunted to extinction by humans.From 1870 the decline of the species became precipitous,and it was officially classified as extinct when the last known representative died on September 1,1914 in the Cincinnati(Ohio)Zoo.Warming UpHawaian chaff flower(夏威夷牛膝草)was everywh

3、ere on the beaches of Hawaii in the 1950s and 1960s.Unfortunately,Hawaii has become a popular destination.The shrubby plants habitat has been eroded by hotels,apartments and tourist developments,leaving it extinct in a short period of time(extinct in 1990).Warming UpPyrenean ibex(比利牛斯山羊),once common

4、ly found in Southern France,Northern Pyrenees and Cantabrian Mountains,was one of the four subspecies of Iberian wild goat or Spanish ibex.They were found in huge numbers even a few hundred years ago.However,by 1900 the numbers went down to less than 100,and after 1910,the number never went up above

5、 40.The last Pyrenean ibex was Celia,a female,found dead in the year 2000.Warming UpExtinction of speciesextinction:a situation in which something no longer existsspecies:a set of animals or plants in which members have similar characteristics to each other1How much do you know about extinction?Choo

6、se the option based on your knowledge.1.How many times up to today has life on Earth almost died out?a.Once b.Five times c.More than 10 times2.About what percent of all species on Earth became extinct during the mass extinction known as the“Great Dying”?a.Less than 10%b.Nearly 50%c.More than 90%Do y

7、ou know any other extinct animals?Share in class.3.What do scientists think will cause the next mass extinction?a.Human activity b.Natural causesc.Unknown reasons Extinction:when a particular type of animal or plant stops existing.(Longman Dictionary 5th Edition)Five times of extinction Reasons 1st:

8、439 million years ago,86%of life on Earth was wiped out2nd:364 million years ago,75%of species were lost3rd:251 million years ago,96%of species were lost4th:199-214 million years ago,many species were lost5th:65 million years ago,ended 76%of life on earth,the extinction of dinosaursActivate and shar

9、eRead the first paragraph and underline the reasons for the five times of extinction.Read the text about extinction and find the main idea for each paragraph.Read and Explorea causes/reasonsb what might happenc what we can dod background history Para.1Para.2Para.3Para.42.Read and explore.Read a text

10、 about extinction.Then check your answers in Activity 1.Extinctions,where entire species are wiped out,are not unusual in our Earths history.In fact,over 90 percent of all species that ever lived are now extinct.In the last 500 million years,there have been five times when life on Earth has almost e

11、nded.These include the third mass extinction,known as the“Great Dying”,which killed 90%to 96%of all species.And the fifth event,which occurred 66 million years ago,caused the death of the dinosaurs.The reasons for extinctions are varied.According to scientists,they include volcanic eruptions,asteroi

12、ds hitting the Earth from space,changes in sea levels,the decrease of the oxygen content of the sea and global warming.Many scientists say we are now entering the Earths sixth mass extinction.This time,human activity will be to blame.非限制性定语从句限制性定语从句限制性定语从句非限制性定语从句非限制性定语从句承上启下 Although it is not unus

13、ual for species to die out naturally,the rate at which this is now happening is cause for concern.A 2015 study by scientists who were based at Brown University and Duke University in the US,looked at,that is,the.They found that human activity is causing species to die out 1,000 times faster than nor

14、mal.There is a long list of reasons why so many species are dying out:air and water pollution,forests being destroyed,factory farming and overfishing.It is clear that human activity has negatively affected all other species on Earth,including animals and plants.双重否定,表示肯定It is adj for sb/sth to do st

15、h做.对某人/某物来说.限制性定语从句限制性定语从句It is adj that.是怎么样的 If a sixth mass extinction occurs,scientists who have studied the issue believe that up to three quarters of all species on Earth could die out.Of course,as we humans depend on so many species for our survival,we would also be at risk of dying out.Our w

16、orld and our lives depend on the balance in nature between animals and plants.Without forests,we would have no air to breathe,and without clean water we would be unable to survive.限制性定语从句宾语从句因为the n between A and BA和B之间的.例：the competition between A and BA和B之间的竞争Can a sixth extinction be avoided?Expe

17、rts say that it is not yet too late,if we take action now.This would mean we have to significantly change the way we live.For example,we need to take steps to save endangered species,including setting up special areas where plants and animals can be protected.We need to change how we work and travel

18、 by using cleaner,more natural sources of energy,such as wind and solar energy.We also need to improve our farming methods to reduce water,air and land pollution.In short,if we want to survive,we need to stop destroying the planet that we live on and start to protect it.be done(动词的过去分词)被动语态限制性定语从句Fo

19、r instance表目的表条件The Black RobinBlack robins are the birds that humans saved from extinction.In 1980,there were only five black robins left in the world.They all lived on a small island off the coast of New Zealand.Only one of those birds,a female called Old Blue,was able to lay eggs.Wildlife workers

20、 began a programme for raising black robin chicks.They protected Old Blues eggs,helped them to hatch,and took care of the chicks.（幼鸟）Thanks to their efforts,there are now more than 250 black robins,and the population（数量）is spreading.To help them survive,people are restoring their habitats and removi

21、ng small animals that hunt them,such as mice and cats from the islands where they live.Case Studyrobin n.知更鸟habitat n.栖息地限制性定语从句定语多亏，由于限制性定语从句Will Humans Survive the Sixth Great Extinction?Suppose you are a member of Green Club in your school.Prepare a speech entitled“Will Humans Survive the Sixth G

22、reat Extinction?”Try to explain the sixth mass extinction,analyze its causes and effects,and offer solutions in your speech.Express yourselfRead the text and use the graphic organizer to show the detailed information about the sixth extinction.Read and ExploreIn the last 500 million years,there have

23、 been five mass extinction events on Earth.In the third event,which 1._ the“Great Dying”,90%to 96%of all species 2._.Of course,species died out due to many causes.But nowadays,human activity 3._ all types of species that we 4._ for living.We need to 5._ to avoid the sixth mass extinction.We should 6

24、._ to save endangered animals and plants,and 7._ special areas to 8._ them before the next extinction comes that may 9._ the entire species.Complete the paragraph about extinctions using the correct form of the phrases below.is known asdied outhas affecteddepend ontake actiontake stepsset uptake car

25、e ofwipe out die out be known as have affected depend on wipe out take steps take action set up take care of Summary As a teenager,what could we do to avoid the sixth extinction?Do not leave the tap running while you brush your teeth.Turn off the light when you go out.Do the garbage classification T

26、ake public transport.DiscussionWill Humans Survive the Sixth Great Extinction?Suppose you are a member of Green Club in your school.Prepare a speech entitled“Will Humans Survive the Sixth Great Extinction?”Try to explain the sixth mass extinction,analyze its causes and effects,and offer solutions in

27、 your speech.Express yourselfThe earth has gone through 5 times of extinction,which are caused by natural activity such as volcanic eruption,asteroids and so on.However,human activity is now to blame for the sixth extinction.The beginning of the speech is already given:When you save water,it saves you back.When you refuse to reuse,its the Earth you abuse.Save the Earth.We have nowhere else to go.