资料简介
选择性必修一 Unit 3 Conservation (1)
The Sixth Extinction
Reading (1)
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extinction
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1. What is extinction?
Extinction is a situation in which something no longer exists.
dinosaur
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2. How much do you know about extinction?
① How many times up to today has life on Earth almost died
out?
A. Once. B. Five times. C. More than 10 times.
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② About which 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%.
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③ What do scientists think will cause the next mass extinction?
A. Human activity. B. Natural causes. C. Unknown reasons.
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Check the answers in the quiz.
① How many times up to today has life on Earth almost died out?
A. Once. B. Five times. C. More than 10 times.
Read and explore
② About which 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%.
③ What do scientists think will cause the next mass extinction?
A. Human activity. B. Natural causes. C. Unknown reasons.
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Get the main idea of each paragraph.
Para. 1:
Para. 2:
Para. 3:
Para. 4:
Background history of the sixth extinction
Causes of the sixth extinction
Effects of the sixth extinction
What we can do to prevent the sixth extinction
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Background history
Causes
Effects
Solutions
The
Sixth
Extinction
Development of the passage
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2. Read the passage again and complete the notes.
Meaning of extinction:
Extinction
The number of extinctions
that have occurred so far:
Two notable extinctions
and their consequences:
Main reasons that
cause extinctions:How to avoid the
sixth mass extinction:
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Meaning of extinction:
Extinctionentire species are
wiped out
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Extinction
The number of extinctions
that have occurred so far:
over 90% of all species
that ever lived
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Extinction
Two notable extinctions and
their consequences:
the third mass extinction killed
90% to 96% of all species; the
fifth event, which occurred 66
million years ago, caused the
death of dinosaurs.
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Extinction
Main reasons that cause extinctions:
volcanic eruptions, asteroids hitting
the Earth from space, changes in sea
levels, the decrease of oxygen
content of the sea, global warming
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Extinction
How to avoid the sixth mass extinction:
change the way we live, including setting up special areas
where plants and animals can be protected; change how
we work and travel by using cleaner, more natural sources
of energy; improve our farming methods
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Retell this part of the passage according to your notes.
Meaning of extinction:
Extinction
The number of extinctions
that have occurred so far:
Two notable extinctions
and their consequences:
Main reasons that
cause extinctions:How to avoid the sixth
mass extinction:
Read and explore
Retelling
Extinction means the entire species are wiped out. So far over 90% of all
species that ever lived are extinct. Along the history, there are 2 notable
extinctions, the third one and the fifth one. During the third mass extinction,
known as the “Great Dying”, 90% to 96% of all species died out. The fifth
one, which occurred 66 million years ago, caused the death of dinosaurs.
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Retelling
There are many reasons that cause extinctions, such as volcanic
eruptions, asteroids hitting the Earth from space, changes in sea levels, the
decrease of oxygen content of the sea and global warming.
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Retelling
The good news is that we can do something to avoid the sixth mass
extinction. Firstly, we have to significantly change the way we live. We need
to take steps to save endangered species, including setting up special areas
where plants and animals can be protected. Also, we can change how we
work and travel by using cleaner and more natural sources of energy, such as
wind and solar energy. We also need to improve our farming methods.
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3. Read the passage again and answer the questions.
① What did scientists find out in 2015?
② Why does the writer think the sixth mass extinction will come?
③ Why does the writer believe we’ll probably die out if 75% of
the Earth’s species die out?
④ What did people do in the case study to protect black robins?
Which claim(s) did the study support in the text?
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① What did scientists find out in 2015?
The study looked at how quickly species die out due to
natural causes, that is, the “background extinction rate”.
They found that human activity is causing species to die out
1,000 times faster than normal.
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② Why does the writer think the sixth mass extinction will
come?
Because human activity has negatively affected all other
species on Earth, including animals and plants.
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③ Why does the writer believe we’ll probably die out if 75% of
the Earth’s species die out?
Because our world and our lives depend on the balance in
nature between animals and plants.
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④ What did people do in the case study to protect black robins?
Which claim(s) did the study support in the text?
Ø People protected Old Blue’s eggs, helped them to hatch, and
took care of the chicks. People are restoring their habitats
and removing pests like mice and cats from the islands where
they live.
Ø What we can do to prevent the sixth extinction
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Causes
Effects
An example of protection
The
Sixth
Extinction
Retell this part of the passage.
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The study in 2015 found that human activity is causing
species to die out 1,000 times faster than normal. It is clear that
human activity has negatively affected all other species on
Earth, including animals and plants.
Retelling
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Retelling
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Retelling
The good news is that people are doing something to protect
animals and plants on Earth. For example, people are taking
measures to protect an endangered bird called Old Blue.
Through our efforts, the number of this bird is increasing
steadily. Therefore, you see, we can do something to help the
earth and it’s never too late to act.
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l reduce waste
l put rubbish into separate dustbins
l cycle or take public transportation
l use fewer plastic bags while going shopping
Summary
Background history
Causes
Effects
Solutions
The
Sixth
Extinction
Homework
Thank you!
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