外研版（2019）选择性必修第二册 Unit 5 A delicate world Understanding ideas 课件（33张PPT）

(共33张PPT)
Unit 5
Unit 5
A delicate world
To get the detail information of the passage
To know how the animals damaged the island
To know what people did to solve the problem
Think how to tackle the problem
What have you know about penguins
Penguins live around the South Pole. They usually spend all their waking hours in the water. Only during the egg-laying and mating periods do penguins actually live on land. Penguins commonly are black with black heads and white breasts. Large penguins often stand about 3 feet in height.
1 Look at the picture below and answer the questions.
1. What animals can you see in the picture
Penguins.
2. What kind of changes would take place if cats, rats and rabbits were introduced to an environment like this
Maybe they could make the environment more active and diverse.
Maybe they would hunt the birds and eat the native vegetation, thus upsetting the local ecological balance.
Read the title and look at the picture. Predict what the passage is mainly about.
MACQUARIE ISLAND:
from Chaos to Conservation
Macquarie Island lies in the South-
west Pacific Ocean, halfway between Australia and Antarctica. Its native inhabitants encountered challenges. Human intervention led to the erosion of the original habitat, cased chaos and destroyed the ecology dramatically.
2 Read the passage and find out what happened to Macquarie Island.
Read the topic sentences;
Link the topic sentences together to get the main idea of the passage;
Draw the outline of the passage;
Match the main idea with its corresponding paragraph.
A. The rabbit problem resulted in parakeets' dying out.
B. The rat, mouse and rabbit problem made people realise that problems should be solved once and for all.
C. I participated in a programme to tackle this very problem.
D. Native inhabitants on Macquarie Island were once in perfect harmony with their natural habitat.
E. People released a virus to kill rabbits and used traps and dogs to catch the cats.
F. Rats and mice brought to the island caused harm.
What happened to the Macquaire Island
Non-native species introduced to Macquarie Island attacked native birds, and led to a substantial reduction of bird population and even the extinction of parakeets. In addition, non-native species ate and devastated the native vegetation. All of this played a part in upsetting the natural harmony of the island. But now the island’s ecology is on the road to recovery with human efforts.
3 Choose the author's purpose in writing the passage and give your reasons.
1. To analyse how Macquarie Island was saved from destruction.
2. To inform readers of the chaos caused on Macquarie Island by humans.
3. To entertain readers with a funny story about what happened on Macquarie Island.
4. To suggest ways in which an ecosystem can be protected.
4 Organise information from the passage and complete the flow chart.
ACTION(S)
Humans arrived on Macquarie Island.
PURPOSE(S)
To live there.
To control the rats and mice.
RESULT(S)
Rats and mice were brought there by accident, and _______.
Rabbits multiplied and caused soil erosion, and ________.
Humans arrived on Macquarie Island.
To live there.
Rats and mice were brought there by accident, and ________________________________________________________________________________
they took over the island, eating the bird’s eggs and attacking baby birds.
ACTION(S)
PURPOSE(S)
RESULT(S)
To control the rats and mice.
Cats were brought to the island.
The cats developed an appetite for the birds.
ACTION(S)
PURPOSE(S)
RESULT(S)
Rabbits multiplied and caused soil erosion, and ________________________________________________________________________________________________________________________________________
Rabbits were introduced to the island.
To provide food for humans.
the exploding rabbit population provided plentiful food for the cats. This led to more cats hunting the birds. As a result, parakeets died out in 1891.
ACTION(S)
PURPOSE(S)
RESULT(S)
A virus was released onto the island.
To remove all the rabbits from the island.
Substantial reduction of rabbit population led to cats killing more native birds.
ACTION(S)
PURPOSE(S)
RESULT(S)
Traps and dogs were used.
To catch the cats.
The departure of the cats resulted in an increasing population of rats and mice. And the rabbit population exploded once again.
ACTION(S)
PURPOSE(S)
RESULT(S)
Poisons and dogs were used.
To remove all the remaining invading species.
The island was pest-free and its ecology is on the road to recovery.
ACTION(S)
PURPOSE(S)
RESULT(S)
Decide whether the following statements are True(T) or False(F).
1. Macquarie Island is a UNESCO World Heritage Site because of its wild and natural beauty. ( )
2. Humans intentionally brought rabbits, rats and mice to the island. ( )
3. Humans brought cats to the island to control the rats and mice. ( )
4. The rabbits had no immunity to the virus released onto the island, so they died out soon. ( )
T
F
T
F
5. Humans learned a lesson from the incident: the rat, mouse and rabbit problem needed solving completely. ( )
6. The programme that the author is to participate in will easily tackle the island's problems. ( )
T
F
A. meaning that the number of cats also increased
B. killing up to 60,000 each year
C. giving it a wild and natural beauty
D. solving once and for all
E. eating the birds’ eggs and attacking baby birds.
1. The green grass and bare rock of its landscape contrast dramatically, _________.
2. Rats and mice quickly took over the island, ________.
C
Complete the sentences.
E
3. The exploding rabbit population provided plentiful food for the cats, _________.
4. The cats in consequence turned their attention – and their stomachs – back to the native birds, _________.
5. The incident made it clear that the rat, mouse and rabbit problem needed, _________.
A. meaning that the number of cats also increased
B. killing up to 60,000 each year
C. giving it a wild and natural beauty
D. solving once and for all
E. eating the birds’ eggs and attacking baby birds.
A
B
D
Below is a summary of the text with some content missing. Choose the right item from the box and make the summary complete.
cat, explode, invade, parakeet, harmony, penguin
Macquarie Island's native inhabitants have existed in perfect 1. ________ for thousands of years. However, humans arrived on the island with rats and mice, which ate birds. 2. ________ were brought to control mice, but they also ate birds. Moreover, rabbits were brought in as food for humans,
harmony
Cats
cat, explode, invade, parakeet, harmony, penguin
but their digging caused soil erosion and increased cat population because cats also ate rabbits. Eventually, the cats also ate 3. ________, which led to their extinction. In the 1980s, traps and dogs were used to catch the cats, and the last cat was finally caught. Without cats, the populations of mice, rats, and rabbits 4. ________ again. The rabbits' digging caused the land to collapse and killed many 5. ________. Finally, humans used helicopters to drop poison in order to remove the last remaining 6. ________ species. In the end, Macquarie Island was pest-free and the island's ecology is finally on the road to recovery.
parakeets
exploded
penguins
invading
Now talk about how human interference led to such severe consequences for Macquarie Island.
1. What is your understanding of “ ... we humans owe it to the island to give it a happy ending”
Nature has its own rules of living. But humans coming caused the destruction of the balance. Because of humans intervention, animals couldn't have their own way of living. So we should whatever we can to make up for our mistakes and give nature back to all the living things.
2. Do you think it was right to eradicate the “pests” from Macquarie Island Give your reasons.
If you agree with the idea, you can use what people do in the passage to help you.
If there's only one species on the island, do you think it is better to the environment
3. How could similar situations be avoided in the future
To avoid similar situations in the future, we should protect the natural ecosystem and be aware of the potential impact that human activities can have on ecosystems.
4. What language can you use to talk about cause and effect How would you apply it to your reading and writing
Nature, to be commanded, must be obeyed.
-- Francis Bacon
Only to obey nature in order to overcome nature.
-- Charles Darwin
We won't have a society if we destroy the environment.
-- Margaret Mead
Why is ecological balance important
How can human beings keep ecological balance