Unit 3 Conservation Lesson 1 The Sixth Extinction 课件(共18张PPT，内镶嵌视频)-北师大版（2019）选择性必修第一册

(共18张PPT)
Lesson 1 The Sixth Extinction
Unit 3
Conservation
How much do you know about extinction Choose the option based on the video.
1. How many times up to today has life on Earth almost died out
a. Once. b. Five times. c. More than 10 times.
2. 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%.
3.Do you think the sixth extinction will happen Who would be to blame to the next mass extinction
a. Human activity. b. Natural causes. c. Unknown reasons.
It may talk about why “The Sixth Extinction” is going to happen and how we can handle the situation.
Can you predict what the text is about according to the title “The Sixth Extinction”
Pre-reading
1. What is the text type of the passage
A. Narration (记叙文). B. Argumentative Essay (议论文).
C. Expository Writing (说明文).D. News Report (新闻报道).
2. Read the text about extinction and find the main idea for each paragraph.
para.1 causes/reasons of extinction
para.2 what might happen
para.3 what we can do
para.4 background history
Fast-reading
A. Narration (记叙文).
B. Argumentative Essay (议论文).
C. Expository Writing (说明文).
D. News Report (新闻报道).
Fast-reading
1. What is the text type of the passage
说明文：旨在解释、阐述某个主题，让读者了解事物的本质、原理、特点等。说明文通常以事实、数据、逻辑推理等方式展开论述。
2. Read the text about extinction and find the main idea for each paragraph.
Para.1
Para.2
Para.3
Para.4
a causes/reasons of extinction
b what might happen
c what we can do
d background history
Fast-reading
background information
Main reasons that cause extinctions
Read Para.1 carefully and complete the detailed information
The sixth extinction
Two notable extinctions and their consequences
The number of extinctions that have occurred so far
Meaning of extinction:
Careful-reading
Extinction
Meaning of extinction
__________________
__________________
The number of extinctions that have occurred so far
______________________________________
Two notable extinctions and their consequences
_____________
Main reasons that cause extinctions
____________
Read Para.1 carefully and complete the detailed information
entire species are wiped out
five times
Background
Information
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
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 the dinosaurs
Read Para. 2 and answer the questions.
1. What did scientists find out in 2015
They found that human activity is causing species to die out 1,000 times faster than normal.
2. What are the main reasons that cause the sixth extinctions
1) Air and water pollution; 2) Forests being destroyed;
3) Factory farming; 4) Overfishing.
Read Para. 3 and answer the question.
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.
Human beings are closely related to nature
Read Para. 4 and answer the question.
4.What can people do to avoid the extinction
Change the way we live;
Set up special areas for endangered species;
Change the way we work and travel;
Improve our farming methods to reduce water, air and land pollution.
Read the case of The Black Robin, what can we conclude from the data of the case.
The case study shows that it is never too late for us to take action to do something to protect our planet.
As a teenager, what should we do to protect the environment.
·Protect wildlife habitat.
· Recycle and buy sustainable products.
· Stop or reduce the use of disposable things such as disposable chopsticks and disposable packaging.
·Never purchase products made from threatened or
endangered species.
....
Discussion
The earth is the home of human beings;
The earth is the cradle（摇篮） of life;
The earth is the foundation of civilization;
Let’s do remember we must conserve the earth and live with the nature in peace.
Compulsory work:
Draw a mindmap and retell the text after class.
Optional work:
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 your speech.
Thank you for listening!