【英语时差8,16】睡眠的意义

Pythons, bats and giant armadillos are among the longest sleepers¹ at over 18 hours a day. Human babies need 16 hours, and most of us probably feel we need around eight hours sleep to function well. Professor Jerry Seigel, from the University of California, Los Angeles, conducted a study of the sleep times of a broad range of animals, and found that they vary widely. Some, like migrating birds, can survive long periods without sleeping at all. He believes that shows sleep evolved to conserve² energy: “It's animals that are needlessly active that will not survive, but animals that are most efficient and use their waking time to do vital functions, and are otherwise asleep that will survive.” Sleep helps make best use of limited resources. In humans, when we're awake, our brain accounts for 20 percent of the energy we use when just sitting around. Sleeping also makes us less likely to get injured and less likely to be detected by predators³.

1 sleepers   

n.卧铺（通常以复数形式出现）；卧车( sleeper的名词复数 )；轨枕；睡觉（呈某种状态）的人；小耳环

参考例句：

• He trod quietly so as not to disturb the sleepers. 他轻移脚步，以免吵醒睡着的人。 来自辞典例句
• The nurse was out, and we two sleepers were alone. 保姆出去了，只剩下我们两个瞌睡虫。 来自辞典例句

2 conserve   

vt.保存，保护，节约，节省，守恒，不灭

参考例句：

• He writes on both sides of the sheet to conserve paper.他在纸张的两面都写字以节省用纸。
• Conserve your energy,you'll need it!保存你的精力，你会用得着的！

3 predators   

n.食肉动物( predator的名词复数 )；奴役他人者（尤指在财务或性关系方面）

参考例句：

• birds and their earthbound predators 鸟和地面上捕食它们的动物
• The eyes of predators are highly sensitive to the slightest movement. 捕食性动物的眼睛能感觉到最细小的动静。 来自《简明英汉词典》