科学美国人60秒 SSS Yawns Help the Brain Keep Its Cool
时间：2018-12-24 作者：英语课 分类：2016年Scientific American(十)月
Not many scientific studies begin like this: "Many hours of watching YouTube clips. Trying to find as many yawns as possible." But for Andrew Gallup, an evolutionary 1 psychologist who studies yawning at the State University of New York, it was all in a day's work.
Gallup says yawns have traditionally been known as a sign of sleepiness, or boredom 2. "But recent evidence suggests that yawning may function to promote brain cooling." The idea being, when you breathe in deeply, the incoming air slightly cools the brain. And stretching the jaw 3 increases blood flow to the brain too--another cooling factor. Reason we do it at night? "At night time when we're about to go to sleep our brain and body temperatures are at their highest point throughout the day."
And so Gallup and his colleagues found themselves hunting for cat videos on the internet--<<cat yawning sound>>--but also clips of dogs, foxes, elephants, gorillas 4, hedgehogs, squirrels, rats, and walruses 5 yawning. They timed all those yawns--then compared them to each species' average brain weight, and the number of neurons in the cerebral 6 cortex.
Their conclusion, published in Biology Letters, was that the length of a yawn was a remarkably 7 good predictor of an animal's brain weight, and cortical neuron number--regardless of the size of its skull 8, or jawbone. [Andrew C. Gallup et al., Yawn duration predicts brain weight and cortical neuron number in mammals] "What that really represents is that yawning likely serves this very basic, and fundamental neurophysiological function." In other words--it helps the brain keep its cool.
--Christopher Intagliata
[The above text is a transcript 9 of this podcast.]
- Life has its own evolutionary process.生命有其自身的进化过程。
- These are fascinating questions to be resolved by the evolutionary studies of plants.这些十分吸引人的问题将在研究植物进化过程中得以解决。
- 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。
- He delivered a right hook to his opponent's jaw.他给了对方下巴一记右钩拳。
- A strong square jaw is a sign of firm character.强健的方下巴是刚毅性格的标志。
- the similitude between humans and gorillas 人类和大猩猩的相像
- Each family of gorillas is led by a great silverbacked patriarch. 每个大星星家族都由一个魁梧的、长着银色被毛的族长带领着。 来自《简明英汉词典》
- Walruses have enormous appetites and hunt for food almost constantly. 海象食欲极大，几乎一直在猎取食物。 来自互联网
- Two Atlantic walruses snuggle on an ice floe near Igloolik, Nunavut, Canada. 加拿大努勒维特伊格卢利克附近，两头大西洋海象在浮冰上相互偎依。 来自互联网
- Your left cerebral hemisphere controls the right-hand side of your body.你的左半脑控制身体的右半身。
- He is a precise,methodical,cerebral man who carefully chooses his words.他是一个一丝不苟、有条理和理智的人，措辞谨慎。
- I thought she was remarkably restrained in the circumstances. 我认为她在那种情况下非常克制。
- He made a remarkably swift recovery. 他康复得相当快。
- The skull bones fuse between the ages of fifteen and twenty-five.头骨在15至25岁之间长合。
- He fell out of the window and cracked his skull.他从窗子摔了出去，跌裂了颅骨。
- A transcript of the tapes was presented as evidence in court.一份录音带的文字本作为证据被呈交法庭。
- They wouldn't let me have a transcript of the interview.他们拒绝给我一份采访的文字整理稿。