【英语时差8,16】生物受激后打哈欠

 Creatures That Yawn When Stimulated¹ If you’ve ever visited a zoo, you’ve probably seen animals yawn. You might have thought those yawns were a result of boredom², but research has suggested that most animals do not yawn for precisely³ the same reasons as humans. Both humans and animals yawn to become more alert, but humans tend to yawn when they are bored or sleepy. And animals yawn in anticipation⁴ of a stimulating⁵ situation. When a human feels bored or sleepy, their blood flow becomes a bit sluggish⁶ and the brain gets less oxygen. As a result, they yawn in order to supply the brain with extra oxygen which helps them become more alert. Most research has suggested that, contrary to common belief, we don’t yawn because our brains need extra oxygen, but because we need to become more alert. Instead of yawning in order to help raise alertness levels during boring situations, animals yawn in anticipation of exciting situations. One baenninger has spent hundreds of hours observing the yawning patterns of several animal species, including lions, monkeys and humans. He found that human beings yawned most often in situations with minimal⁷ stimulation⁸, but in which alertness was important, such as driving late at night; they yawned least often during physically⁹ stimulating situations such as an aerobics¹⁰ class. Captive lions and monkeys, on the other hand, yawned most often just before feeding time, one of the most stimulating times of the day. Other scientists have also observed laboratory rats yawning just prior to eating. These studies suggest that animals yawn in anticipation of stimulation rather than as a result of boredom.

1 stimulated   

a.刺激的

参考例句：

• The exhibition has stimulated interest in her work. 展览增进了人们对她作品的兴趣。
• The award has stimulated her into working still harder. 奖金促使她更加努力地工作。

2 boredom   

n.厌烦，厌倦，乏味，无聊

参考例句：

• Unemployment can drive you mad with boredom.失业会让你无聊得发疯。
• A walkman can relieve the boredom of running.跑步时带着随身听就不那么乏味了。

3 precisely   

adv.恰好，正好，精确地，细致地

参考例句：

• It's precisely that sort of slick sales-talk that I mistrust.我不相信的正是那种油腔滑调的推销宣传。
• The man adjusted very precisely.那个人调得很准。

4 anticipation   

n.预期，预料，期望

参考例句：

• We waited at the station in anticipation of her arrival.我们在车站等着，期待她的到来。
• The animals grew restless as if in anticipation of an earthquake.各种动物都变得焦躁不安，像是感到了地震即将发生。

5 stimulating   

adj.有启发性的，能激发人思考的

参考例句：

• shower gel containing plant extracts that have a stimulating effect on the skin 含有对皮肤有益的植物精华的沐浴凝胶
• This is a drug for stimulating nerves. 这是一种兴奋剂。

6 sluggish   

adj.懒惰的，迟钝的，无精打采的

参考例句：

• This humid heat makes you feel rather sluggish.这种湿热的天气使人感到懒洋洋的。
• Circulation is much more sluggish in the feet than in the hands.脚部的循环比手部的循环缓慢得多。

7 minimal   

adj.尽可能少的，最小的

参考例句：

• They referred to this kind of art as minimal art.他们把这种艺术叫微型艺术。
• I stayed with friends, so my expenses were minimal.我住在朋友家，所以我的花费很小。

8 stimulation   

n.刺激，激励，鼓舞

参考例句：

• The playgroup provides plenty of stimulation for the children.幼儿游戏组给孩子很多启发。
• You don't get any intellectual stimulation in this job.你不能从这份工作中获得任何智力启发。

9 physically   

adj.物质上，体格上，身体上，按自然规律

参考例句：

• He was out of sorts physically,as well as disordered mentally.他浑身不舒服，心绪也很乱。
• Every time I think about it I feel physically sick.一想起那件事我就感到极恶心。

10 aerobics   

n.健身操，健美操，韵律操

参考例句：

• Doing aerobics is a good way to improve one's health.做有氧健身操是改善健康状况的一个好方法。
• Aren't you going to the aerobics class this morning?今天上午你不是去上有氧运动课吗？