Discussion. 1. What do educators say about homework?

1. What do educators say about homework?

2. Which of the ideas about homework would you rather support and why?

3. What ratio of homework and classwork is the best?

4. How does the role of homework change as students become older and more mature?

THE RARE AND THE WILD

Pre-reading task

1. On a separate piece of paper write down as many animal species as you know. Compare your list with your partner’s.

2. Which of the animals included in the list are rare? Why do you think they are under the threat of extinction?

The Earth is only a small planet, but it is an unusually beautiful one. It is rich with plant and animal life. In their short stay on Earth, humans have only begun to understand the other life in the biosphere around them. As life on Earth has slowly changed over millions of years, new kinds of plants and animals have developed and others have died out, or become extinct. This process still goes on. Just as the last of the dinosaurs died out sixty-five million years ago, other kinds of animals are becoming extinct today.

Someday, even humans may become extinct. Before that happens, however, the activities of humans will have sped the extinction of hundreds of kinds of other living things. Today more than five hundred kinds of animals are listed as rare or endangered. The blue whale is simply being hunted to death. Other kinds of animals die out because their special living areas, or habitats, are destroyed. The Everglades kite, for example, is a bird that depends on a single kind of snail for most of its food. The marshes and lakes of Florida where the snails live are being destroyed by humans. The kite cannot adapt to a new kind of food, so its numbers drop as its habitat shrinks in size.

You may ask, "Does it really matter if people cause the extinction of this bird? It probably would have died out in a few hundred more years anyway?"

Some answers to this question come from biologists, the scientists who study living things. They point out that each creature on Earth is unique. Just as humans are unique in some ways, so too are other animals. As citizens of the Earth, humans have no right to wipe out other creatures. Once gone, a species cannot be brought back. For all their power, humans cannot make a whooping crane or a grizzly bear. Biologists are especially concerned that humans may simplify life on Earth too much. They have noticed the problems that sometimes occur in the Arctic, where the communities of plants and animals are very simple. Not many plants and animals can survive in the Arctic. Those that live there depend on a few other living things for life. If one part of the system is damaged, many other parts may be affected. Arctic plant-animal communities are easily damaged by humans or by some natural disturbance. Once upset, it may take centuries for the system to recover.

The opposite is true in the lush tropics. There the plant-animal communities are much more complex. There are many kinds of living things and they are not dependent on just a few other plants and animals, as in the Arctic. The numbers of animals don't change greatly from year to year, as they often do in the Arctic. When tropic communities are damaged by humans, they usually recover quickly. You can see why biologists want to keep the Earth as full of a variety of life as possible. Already, in farming, the dangers of simplifying life can be seen. A farmer may plant hundreds of acres to a single crop, keeping out weeds and getting rid of fence rows where a variety of life might live in the brush and weeds. The huge planting of a single crop is an invitation to an outbreak of a disease or an insect pest. The pests can thrive but there is no habitat for the birds or other enemies that might normally control the harmful insects.

The farmer may be able to protect a crop with poisons, but the danger of a crop disaster is always present. The plants could also be protected by a network of brushy fence rows that support a variety of life, including birds and insects that prey on insect pests. Biologists point out another reason for treasuring each bit of life on Earth. Some of our great gains in science and medicine have come from research upon some plant or animal that seemed of little value at the time. New knowledge about human blood came from the study of rhesus monkeys. Research on wolves and baboons is giving scientists a better understanding of the behavior of all mammals. For our own welfare, then, we ought to make sure that a great variety of life survives on the Earth.

To maintain that variety, humans must make sure that many kinds of plant-animal communities exist. In the United States, some of these communities are saved in wilderness areas, wildlife refuges, and in national and state parks. With so much of North America already changed by people, these areas have special value as "outdoor laboratories" for study of the natural world. But many other wild areas are disappearing. As we build more highways, factories, houses, and shopping centers, we wipe out entire habitats – draining a swamp, cutting down a forest, flooding a valley. In each case, humans have lost a place where they can learn about the natural world of which they are but a part.

In some parts of the world the human population is so great that it has already caused the destruction of most wild land and the extinction of many kinds of animals. In parts of Africa, the wild hoofed animals are being wiped out so that cattle can be raised. The cattle do not do well, however, because of diseases and low rainfall. They strip most of the plant life from the land, wiping out their own food supply and leaving the soil exposed, to be washed away by rain or blown away by the wind. Biologists believe that the land would produce more food for humans if the native wild game was allowed to live there. But the slaughter of wildlife goes on. The situation is even worse in India, a country that was once rich with wildlife. Food is scarce for India's 500 million people. Wild animals are thought of only as food, or as a threat to crops.

The habitat of many Indian animals has been destroyed, and wildlife must compete for food with vast herds of cattle and buffalo. The numbers of wild animals drop even lower due to shooting by poachers, who kill for meat even within the borders of India's few parks and game refuges. As a result, some animals found nowhere else on Earth have vanished, even before they could be studied in the wild. Many other kinds of animals, such as the Asiatic lion and the one-horned rhinoceros, are close to extinction. Even in the United States, where concern for wild animals is great, the survival of some species is threatened because of greed or ignorance. The numbers of American alligators dropped low because their skins are so valuable when used in handbags and shoes. Recent laws forbid the sale of products made from alligator skins, and these laws may stop the illegal killing of these reptiles.In the northern United States and in Canada, people are still shooting, trapping, and poisoning wolves. Many people think of wolves as dangerous, "bad" animals. But biologists have discovered that wolves have many good effects in the wild areas where they live.

Wolves eat large plant-eating animals such as moose. The wolves usually kill those moose that are easiest to catch-the injured, the sick, the old. In this way they help to keep the moose population healthy. By keeping the population under control, the wolves also help prevent the moose from becoming so plentiful that they destroy their own food supply. In areas where wolves have been wiped out, populations of animals such as moose, deer, and elk often get out of control. The population increases until the animals run out of food and starve, or until a disease sweeps through the herd. This was the problem at Yellowstone National Park, where thousands of elk had to be removed or killed each year in order to keep the herd in balance with its food supply. Some biologists suggested that wolves be brought to Yellowstone, where they once served as natural controls on the elk population. Now the wolves are at Yellowstone once more.

Bringing wolves back to Yellowstone will help the wolf species to survive. It also helps bring a national park a bit closer to its original wildness and makes it a better outdoor laboratory where scientists can study nature. If humans are to understand nature, they must find ways like this to save the rare and the wild.

extinct – той, що счез

to speed – прискорювати

to be endangered – бути у небезпеці счезнення

to die out -вимирати

marsh – болото

kite -коршун

to shrink – зменшуватися, скорочуватися, стягуватися

to wipe out – зтирати, знищувати

whooping crane – різновид

lush tropics – багата рослинність тропіків

weeds -буряни

to get rid of – позбавлятися, знешкоджувати

outbreak of a disease – спалах епідемії

pest – сільськогосподарський шкідник

to thrive -процвітати

mammals -ссавці

wilderness – [ w i l d q n i s ] -пустеля

wildlife refuge – заповідник, заповідна зона

valley – долина

hoofed animals – копитні тварини

slaughter – [ s l L t q ] –- кровопролиття, різанина

scarce – [ s k F q s ] -рідкий

herds -стада

ignorance – [ i g n q r q n s ]

Discussion:

1. Why do you think people have allowed so many animals to become rare and endangered?

2. What is being done in your area to preserve wildlife? Do you think enough is being done? If not, what else do you think should be done? What can you do personally?

3. Do you agree with the statement that "Someday, even humans may become extinct"? Why or why not?

4. According to the author what are some causes that contribute to the extinction of animals? What might be some other causes?

5. What does the author mean by the statement, "Biologists are especially concerned that humans may simplify life on Earth too much"?

6. Explain how some farming methods have endangered wildlife.

7. Wolves have been thought of as dangerous, "bad" animals. How does the author show that wolves have good effects on the balance of nature?

Why do people emigrate?

Дата добавления: 2015-10-02