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Extinction—extinguisher
To keep pace with
Catch up with
Competitor—competition—competitive—competitiveness
Likely=possible
---likelihood=possibility
vegetable—vegetarian
ignorance—look over
threaten—threatened—threatening
decoration
vary—various—vary…from…
survival—survivor
conserve—protect—protection
book—order
reservation
provided that
providing that
provided that you can keep my book well, I will lend it to you.
Ward
Determine to do sth.
Decide to do sth.
Decision
Conflict
LESSoN NINETEEN
TEXT A
Animals at Risk : Who Cares?
An animal species becomes extinct when it fails to produce enough young in each generation to keep pace with the death-rate. We can tell from fossil evidence in rocks that many living species have become extinct over the millions of years since life began. It is a natural process and extinction is the fate of any animal that has specialized too far to change when its environment changes, or has to compete with a better-adapted and more powerful animal. Because of remarkable technical developments during the past few centuries, man has destroyed or nearly destroyed some species by killing them at such a rate that they couldnt produce enough offspring, or by completely changing their natural environment at surprising speed.
A number of examples can be given of the way in which natural environments are being rapidly changed -- Amazonia, for instance. There is every likelihood that many species of animals will be made extinct because of these and similar clearances of natural vegetation. Large numbers of animals have been hunted and killed for food. The North American buffalo is a case of the near-extinction of a species through hunting. often the numbers are so great the hunters may not realize the danger. But even when the danger is widely publicized, the financial rewards for the hunters may be so great that they choose to ignore the threat to the species. Attitudes like this have led to hunters killing animals for furs, for ivory or merely for ornaments. A slight variation on this is when tourists hunt animals for trophies. Magnificent creatures such as lions and tigers have been hunted out of existence in some parts of the world. It is important to realize, though, that animals are sometimes killed out of fear. Big cats are killed in this way. And animals are sometimes killed out of a wish to reduce numbers to help the species to survive. The killing of the Canadian seals is claimed to be for this purpose, and the use of their skins for furs is only a by-product.
Many people are concerned about animals and wildlife conservation. one way to preserve species under threat of extinction -- whatever the cause -- is to remove them to zoos and parks and breed them there. There is always the chance that enough offspring will be born to return them one day to their natural environment -- provided it still exists, and that hunters dont kill them again! Another method is to protect the animals in their natural environment by creating wildlife reserves and parks and using game wardens to look after them. But the parks are large, the wardens few and the determination of hunters very great. Early in 1980 wardens and hunters clashed in East Africa. The hunters were armed with modern weapons and several people were killed.
There is great pleasure in watching wildlife in natural or near-natural environments, and tourism can add to the income of countries. The animals are still resources -- but in a very different form.
n. 可能性
