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 psychologist who studies yawning at the State University of New York, it was all in a day's work.并没有很多科学研究是像这样开始的：“长时间观看YouTube网视频，并找到尽可能多的打哈欠视频。”但是，对于纽约州立大学研究哈欠的进化心理学家安德鲁·盖洛普来说，这却是每天的日常工作。 Gallup says yawns have traditionally been known as a sign of sleepiness, or boredom. "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 thejawincreases 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 that's when we see the highest frequency of yawning."盖洛普表示，哈欠通常被认为是困倦或无聊的征兆。"但是最近有证据表明，打哈欠可以帮助大脑冷却。"思路是，当你深呼吸时，吸入的空气会使大脑降温。而伸展下巴会增加血液流入大脑——这是导致大脑降温的另一个因素。为什么我们经常在晚上打哈欠呢?"因为晚上我们要入睡时，我们的大脑温度和体温达到一天当中的最高点。所以那个时间是我们打哈欠频率最高的时候。" And so Gallup and his colleagues found themselves hunting for cat videos on the internet (cat yawning sound) — along with clips of dogs, foxes, elephants, gorillas, hedgehogs, squirrels, rats, and walruses yawning. They timed all those yawns — and then compared them to each species' average brain weight, and the number of neurons in the cerebral cortex.所以盖洛普和他的同事在网上寻找猫咪打哈欠的视频(猫咪打哈欠的声音)，他们还找了狗、狐狸、大象、大猩猩、刺猬、松鼠、老鼠以及海象打哈欠的视频。他们统计这些动物打哈欠的时长，然后将其与各物种的大脑平均重量以及大脑皮层神经元的数量进行比较。 Their conclusion, published in Biology Letters, was that the length of a yawn was a remarkably good predictor of an animal's brain weight, and corticalneuron number — regardless of the size of its skull, or jawbone. "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.该研究结果发表在《生物学快报》期刊上，他们得出的结论是：哈欠的长度能非常准确地预测动物大脑的重量以及皮质神经元的数量，而且可以忽略掉动物骨骼以及头骨的大小。"研究结果真正表明的是，打哈欠具有基本的神经生理功能。换言之，它可以帮助大脑降温。"
单词解析
1. clip [klɪp]n. (电影、广播、电视节目的) 片断e.g.He was watching an historical film clip of Lenin speaking.他正在看一段列宁讲话的历史电影片断。 2. yawn[jɔːn]n. 哈欠；裂口e.g.Rosanna stifled a huge yawn.罗莎娜忍住了一个大哈欠。 3. jaw[dʒɔː]n. 颌；下巴；狭窄入口；唠叨e.g.He thought for a moment, stroking his well-defined jaw.他抚摸着他棱角分明的下巴想了一会儿。 4. gorilla [gə'rɪlə]n. 大猩猩e.g.In many jungle films, the gorilla is seen as a fierce hunter, much like the leopard or the lion. 在很多丛林的影片中，大猩猩被看作凶猛的猎手，很像美洲豹或狮子。 5. hedgehog['hedʒ(h)ɒg]n. 刺猬e.g.A frightened hedgehog contracts its body into a ball .受惊的刺猬会把身体缩成一个球。 6. squirrel['skwɪr(ə)l]n. 松鼠；松鼠毛皮e.g.It was moving fast like a squirrel, but it was as loud as a bear. 它像松鼠一样快速的移动但那声音却像是熊发出的似的。 7. walrus ['wɔːlrəs]n. 海象e.g.Walrus need either ice or land to rest. 海象的主要休息地为冰面或陆地。 8. neuron ['njʊərɒn]n. [解剖] 神经元，神经单位e.g.The findings were published in the journal Neuron. 这一研究成果发表在《神经元》杂志上。 9. cerebral['serɪbr(ə)l]adj. 大脑的，脑的e.g.Meditation can increase the thickness of the cerebral cortex, particularly in regions associated with attention and sensation. 冥想能增加大脑皮质的厚度，特别是在与注意和感觉相关的区域。 10. cortex['kɔːteks]n. [解剖] 皮质；树皮；果皮e.g.But they do not stay there long. Instead, they are sent to the prefrontal cortex for longer-term storage. 但是这些记忆并不会在那里停留很长时间，而是会被发送到前额皮质以备长期储存。 11. cortical ['kɔːtɪkəl]adj. 皮质的；[生物] 皮层的；外皮的e.g.This allowed them to compare cortical differences in the brain between the two sample groups. 这使研究者能够比较两组样本之间的大脑皮质差异。 12. skull[skʌl]n. 头盖骨，脑壳e.g.Her husband was later treated for a fractured skull.她丈夫后来因颅骨碎裂而接受治疗。 13. jawbone ['dʒɔːbəʊn]n. 颚骨；下颚骨e.g.A tourist in Aruba discovered a jawbone last week.上周，阿鲁巴岛的一名游客发现了一个颚骨。 14. neurophysiological['nju:rəʊ,fɪzɪə'lɒdʒɪkəl]adj. 神经生理的e.g.A new field of study referred to as neurotheology has been advancing the study of the neurophysiological correlation between prayer and subjective experience.一个被称为神经神学的新的研究领域正在推进有关在祈祷和个人经验之间的神经生理相关性的研究。
