四六级

2017上半年六级英语口语练习题:睡眠的进化

时间:2017-03-23 来源:文都网校 浏览: 分享:

      在英语考试中,英语口语对于很多同学来说,是一块软肋,在2017上半年英语六级口语备考中,多练习才是硬道理,下面是文都网校小编为您整理的2017年6月六级英语口语练习题资料。赶紧跟你的小伙伴儿一起来练习口语吧~

      2017上半年英语六级口语场景对话练习汇总

       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 sensethat 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 Meddis 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

      2017上半年英语六级口语场景对话练习汇总

      每天多读多练习,英语口语没问题!2017年6月英语四六级备考之路,文都网校四六级资讯站愿助您一臂之力!更多2017年6月英语四六级备考资讯,请点击文都网校四六级资讯站!

    文都名师助力2017年6月英语四六级考试通关课程
    2017年6月大学英语四级VIP定制班 2017年6月大学英语六级VIP定制班

     

    文都网校四六级学习群1:1139836391【加群

    文都网校四六级学习群2:1053314777【加群

    文都网校四六级学习群3:821773913【加群

    文都网校四六级学习群4:887259542【加群

    热门课程
    热文排行