tailieunhanh - Cracking the toefl ibt part 7

Toefl luôn là sự đòi hỏi hàng đâu khi đi xin việc hay làm việc tại nước ngoài. Không dễ dàng để nói, nghe, đọc hay viết tiếng anh một cách rõ rang. Nó đòi hỏi chúng ta phải có một qua trình tập luyện rất vất vả. Tài liệu này là một phần giúp chúng ta học tiếng anh thêm dễ dàng. | Each ant selflessly performs its role not for its own benefit but for the benefit of all the other ants. Now entomologists have found an interesting case of this sort of cooperation in a nonsocial insect the cricket. Crickets are a prime example of a selfish insect leading a very isolated existence. They typically interact1 with other crickets only when mating or fighting over territory. But scientists have observed a species of cricket that undergoes periodic mass migrations. Every so often the crickets set off to find more favorable living areas. When these migrations occur the crickets band together Into a huge caravan. Surely at a time like this the crickets realize there is safety in numbers and put aside their selfish instinct for the good of all members. Now read the following lecture on the same subject Professor One of the biggest misconceptions in biology is the belief that organisms act out of concern for the greater good of the species. It is somewhat amazing how people assume that an ant or a mouse has enough sense to figure out how its actions impact all the members of its species Still it is understandable why many people might believe this erroneous view. Many actions can be misinterpreted as being for the good of the species. A classic example found in many early biology textbooks discussed the behavior of the stag. During mating season a stag typically battles with other males and the winner of these contests gains access to the females while the loser walks away. Some people believed that the loser realizes that his offspring will be weaker so the defeated stag allows the winner to mate to ensure the survival of the stag species. This couldn t be further from the truth. The defeated stag wants to mate just as much as the winner does the only problem is that he doesn t want to risk his life for the chance to mate. The stag is better off looking for other females to mate with. Thus both stags the winner and the loser are acting not for the good of