Reading 1: Exotic and endangered species

                                        EXOTIC AND ENDANGERED SPECIES

When you hear someone bubbling enthusiastically about an exotic species, you can safely bet the speaker isn’t an ecologist. This is a name for a resident of an established community that was deliberately or accidentally moved from its home range and became established elsewhere. Unlike most imports, which can’t take hold outside their home range, an exotic species permanently insinuates itself into a new community.

Sometimes the additions are harmless and even have beneficial effects. More often, they make native species endangered species, which by definition are extremely vulnerable to extinction. Of all species on the rare or endangered lists or that recently became extinct, close to 70 percent owe their precarious existence or demise to displacement by exotic species. Two examples are included here to illustrate the problem.

During the 1800s, British settlers in Australia just couldn’t bond with the koalas and kangaroos, so they started to import familiar animals from their homeland. In 1859, in what would be the start of a wholesale disaster, a northern Australian landowner imported and then released two dozen wild European rabbits (Oryctolagus cuniculus). Good food and good sport hunting – that was the idea. An ideal rabbit habitat with no natural predators was the reality.

Six years later, the landowner had killed 20,000 rabbits and was besieged by 20,000 more. The rabbits displaced livestock, even kangaroos. Now Australia has 200 to 300 million hippityhopping through the southern 4 half of the country. They overgraze perennial grasses in good times and strip bark from shrubs and trees during droughts. You know where they’ve been; they transform grasslands and shrub lands into eroded deserts. They have been shot and poisoned. Their warrens have been plowed under, fumigated, and dynamited. Even when all-out assaults reduced their population size by 70 percent, the rapidly reproducing imports made a comeback in less than a year. Did the construction of a 2,000-mile-long fence protect Western Australia? No. Rabbits made it to the other side before workers finished the fence.

In 1951, government works introduced a myxoma virus by way of mildly infected South American rabbits, its normal hosts. This virus causes myxomatosis. The disease has mild effects on South American rabbits that coevolved with the virus but nearly always had lethal effects on O. cuniculus. Biting insects, mainly mosquitoes and flenses against the novel virus, the European rabbits dies in droves. But, as you might expect, natural selection has since favored rapid growth of populations of O. cuniculus resistant to the virus.

In 1991, on an uninhabited island in Spencer Gulf, Australian researchers released a population of rabbits that they had injected with a calcivirus. The rabbits died quickly and relatively painlessly from blood clots in their lungs, hearts, and kidneys. In 1995, the test virus escaped from the island, possibly on insect vectors. It has been killing 80 to 95 percent of the adult rabbits in Australian regions. At this writing, researches are now questioning whether the calcivirus should be used on a widespread scale, whether it can jump boundaries and infect animals other than rabbits (such as humans), and what the long – term consequences will be.

A vine called kudzu (Puerarialobata) was deliberately imported from Japan to the United States, where it faces no serious threats from herbivores, pathogens, or competitor plants. In temperate parts of Asia, it is a well – behaved legume with a well – developed root system. It seemed like a good idea to use it to control erosion on hills and highway embankments in the southeastern United States. (A) With nothing to stop it, though, kudzu’s shoots grew a third of a meter per day. Vines now blanket stream banks, trees, telephone poles, houses, and almost everything else in their path. Attempts to dig up or burn kudzu are futile. Grazing goats and herbicides help, but goats eat other plants, to, and herbicides contaminate water supplies. (B) Kudzu could reach the Great Lakes by the year 2040.

On the bright side, a Japanese firm is constructing a kudzu farm and processing plant in Alabama. The idea is to export the starch to Asia, where the demand currently exceeds the supply. (C) Also, kudzu may eventually help reduce logging operations. (D) At the Georgia Institute of Technology, researchers report that kudzu might become an alternative source for paper.

Question: 

1. Based on the information in paragraph 1, which of the following best explains the term “exotic species”?

A. Animals or plants on the rare species list

B. A permanent resident in an established community

C. A species that has been moved to a different community

D. An import that fails to thrive outside of its home range

2. The world itself in the passage refers to

A. most imports        B. new community   C. home range           D. exotic species

3. The word bond in the passage is closest in meaning to

A. move B. connect C. live D. fight

4. According to the author, why did the plan to introduce rabbits in Australia fail?

A. The rabbits were infected with a contagious virus.

B. Most Australians did not like the rabbits.

C. No natural predators controlled the rabbit population.

D. Hunters killed the rabbits for sport and for food.

5. All of the following methods were used to control the rabbit population in Australia EXCEPT

A. They were poisoned.

C. They were moved to deserts.

B. Their habitats were buried.

D. They were surrounded by fences

6. Why does the author mention mosquitoes and fleas in paragraph 5?

A. Because they are the origin of the myxoma virus

B. Because they carry the myxoma virus to other animals

C. Because they die when they are infected by myxoma

D. Because they have an immunity to the myxoma virus

7. According to paragraph 6, the Spencer Gulf experiment was dangerous because

A. insect populations were exposed to a virus
 B. rabbits on the island died from a virus

C. the virus may be a threat to humans
D. some animals are immune to the virus

8. Why does the author give details about the kudzu farm and processing plant in paragraph 8?

A. To explain why kudzu was imported from abroad

B. To argue that the decision to plant kudzu was a good one

C. To give a reason for kudzu to be planted in Asia

D. To offer partial solutions to the kudzu problem

9. Which of the following statements most accurately reflects the author’s opinion about exotic species?

A. Exotic species should be protected by ecologists.

B. Importing an exotic species can solve many problems.

C. Ecologists should make the decision to import an exotic species.

D. Exotic species are often disruptive to the ecology.

10. Look at (A), (B), (C), (D) in the last two paragraphs. Where the following sentence could be best inserted in the passage

(A), (B), (C), or (D)? Asians use a starch extract from kudzu in drinks, herbal medicines, and candy.

Key:

1.C

When you hear someone bubbling enthusiastically about an exotic species, you can safely bet the speaker isn’t an ecologist. This is a name for a resident of an established community that was deliberately or accidentally moved from its home range and became established elsewhere. Unlike most imports, which can’t take hold outside their home range, an exotic species permanently insinuates itself into a new community.

2.D

When you hear someone bubbling enthusiastically about an exotic species, you can safely bet the speaker isn’t an ecologist. This is a name for a resident of an established community that was deliberately or accidentally moved from its home range and became established elsewhere. Unlike most imports, which can’t take hold outside their home range, an exotic species permanently insinuates itself into a new community.

3.B

bond: develop or create a relationship of trust with somebody

=> The answer is connect

4.C

During the 1800s, British settlers in Australia just couldn’t bond with the koalas and kangaroos, so they started to import familiar animals from their homeland. In 1859, in what would be the start of a wholesale disaster, a northern Australian landowner imported and then released two dozen wild European rabbits (Oryctolagus cuniculus). Good food and good sport hunting – that was the idea. An ideal rabbit habitat with no natural predators was the reality.
 

5.C

Six years later, the landowner had killed 20,000 rabbits and was besieged by 20,000 more. The rabbits displaced livestock, even kangaroos. Now Australia has 200 to 300 million hippityhopping through the southern 4 half of the country. They overgraze perennial grasses in good times and strip bark from shrubs and trees during droughts. You know where they’ve been; they transform grasslands and shrub lands into eroded deserts. They have been shot and poisoned. Their warrens have been plowed under, fumigated, and dynamited. Even when all-out assaults reduced their population size by 70 percent, the rapidly reproducing imports made a comeback in less than a year. Did the construction of a 2,000-mile-long fence protect Western Australia? No. Rabbits made it to the other side before workers finished the fence.

A. They were poisoned.

B. Their habitats were buried.

C.  They were moved to deserts.

D. They were surrounded by fences.

6.B

In 1951, government works introduced a myxoma virus by way of mildly infected South American rabbits, its normal hosts. This virus causes myxomatosis. The disease has mild effects on South American rabbits that coevolved with the virus but nearly always had lethal effects on O. cuniculus. Biting insects, mainly mosquitoes and flenses against the novel virus, the European rabbits dies in droves. But, as you might expect, natural selection has since favored rapid growth of populations of O. cuniculus resistant to the virus.

7.C

In 1991, on an uninhabited island in Spencer Gulf, Australian researchers released a population of rabbits that they had injected with a calcivirus. The rabbits died quickly and relatively painlessly from blood clots in their lungs, hearts, and kidneys. In 1995, the test virus escaped from the island, possibly on insect vectors. It has been killing 80 to 95 percent of the adult rabbits in Australian regions. At this writing, researches are now questioning whether the calcivirus should be used on a widespread scale, whether it can jump boundaries and infect animals other than rabbits (such as humans), and what the long – term consequences will be.

8.D

On the bright side, a Japanese firm is constructing a kudzu farm and processing plant in Alabama. The idea is to export the starch to Asia, where the demand currently exceeds the supply. (C) Also, kudzu may eventually help reduce logging operations. (D) At the Georgia Institute of Technology, researchers report that kudzu might become an alternative source for paper.

9.D

From the example about exotic species, the author mentioned the disater caused by them and showed his disagreement to exotic species.

10.C

The sentence: Asians use a starch extract from kudzu in drinks, herbal medicines, and candy.  mentions the advantages of kudzu in daily life, with the role of food, drinks and medicines.

Paragrph 7 mainly discusses the role of kudzu in controling erosion and how to decrease the area of kudzu

 => Not choose A and B

Paragraph 8:

(D) stands before the use of kudzu to make paper => There is no relation.

(C) The sentence after C has “ Also”, the sentence before C has “ Asia, supply”

=> Choose C