新托福写作考试想拿到高分非常不容易，但是参加新托福写作考试的同学都想要拿到高分，那么研究一两篇优秀范文，可以让我们了解新托福写作的高分要素。
范文的题目：Evolution of sleep。
Sleep is very ancient. In the electroencephalographic sense we share it with all the primates and almost all the other mammals and birds: it may extend back as far as the reptiles.
There is some evidence that the two types of sleep, dreaming and dreamless, depend on the life-style of the animal, and that predators are statistically much more likely to dream than prey, which are in turn much more likely to experience dreamless sleep. In dream sleep, the animal is powerfully immobilized and remarkably unresponsive to external stimuli. Dreamless sleep is much shallower, and we have all witnessed cats or dogs cocking their ears to a sound when apparently fast asleep. The fact that deep dream sleep is rare among pray today seems clearly to be a product of natural selection, and it makes sense that today, when sleep is highly evolved, the stupid animals are less frequently immobilized by deep sleep than the smart ones. But why should they sleep deeply at all? Why should a state of such deep immobilization ever have evolved?
Perhaps one useful hint about the original function of sleep is to be found in the fact that dolphins and whales and aquatic mammals in genera seem to sleep very little. There is, by and large, no place to hide in the ocean. Could it be that, rather than increasing an animal’s vulnerability, the University of Florida and Ray Middies of London University have suggested this to be the case. It is conceivable that animals who are too stupid to be quite on their own initiative are, during periods of high risk, immobilized by the implacable arm of sleep. The point seems particularly clear for the young of predatory animals. This is an interesting notion and probably at least partly true.
>>点击查看托福写作备考全集合专题，阅读更多相关文章！
-
托福写作字数和实际得分关系深度分析 合理安排写作篇幅让文章内容更有料
托福考生对于写作部分的字数要求一直存有疑问。写得字数太少担心被扣分，写得太多时间又会不够用。如何才能把握好作文字数和实际得分之间的关系呢?本文将为大家深度分析托福写作字数和得分的关系，帮助大家了解托福写作的正确篇幅安排。
- 备考托福写作范文资料备考如何高效运用？这3个练习重点不容忽视
- 托福独立写作开头段写法基础4步骤讲解 循序渐进让高分作文开个好头
- 托福写作7种常用高分句型汇总分享 结合句式实例提升写作用句水平
- 托福写作机经正确使用方法技巧和注意事项一览 掌握用法才能发挥机经价值