人類進化結(jié)果睡眠更少,更好

　　Humans are efficient sleepers, and that's why weneed less sleep - seven hours - compared to as muchas 14 hours a day for our closest animal relatives,

　　人類的睡眠很有效，這也是為什么我們睡得更少，一天只睡7個小時而不是離我們最近的物種所需的多達14個小時。

　　Researchers at Duke University compiled a databaseof sleep patterns of hundreds of mammals, including21 primate species. They found that not only dohumans need less sleep than chimps, macaques andlemurs, we spend a greater percentage of ourslumber in the deeper, more restorative stages of sleep.

　　美國杜克大學的研究人員建立了一個幾百種哺乳動物睡眠規(guī)律的數(shù)據(jù)庫，其中包括21種靈長類動物。他們發(fā)現(xiàn)，人類睡眠時間不僅比黑猩猩、獼猴和狐猴要少，而且更多時間是沉睡在更深、更有恢復作用的階段。

　　That might not seem surprising in this age of electric lights and round-the-clock activities, butco-author David Samson says this shift began long before we developed artificial lighting. Hetraces it back to when human ancestors left their nests in the trees for sleeping on the ground.

　　在這個有電燈和通宵工作的時代這也許并不令人驚訝。但是這份報告的共同作者大衛(wèi)·薩姆森說，睡眠的這種變化早在我們發(fā)明人工照明之前就開始了。他將這一變化追溯到人類祖先離開樹巢開始睡在地上的時候。

　　The need to sleep near fire and in larger groups for warmth and safety could have allowed theseearly humans to get the most out of their sleep in the shortest possible time. He notes that alsoleft more time for other activities, like learning new skills.

　　由于睡覺時需要靠近火和更大的人群保持溫暖和安全，這可能使得早期人類盡可能在最短時間內(nèi)睡得最好。薩姆森提到這也留給人類更多的時間做其他活動，比如學習新技能。