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(单词翻译:双击或拖选)
A lot of people have had impacted third molars. Third molars produce a lot of chronic1 pain.
Alan Mann, a Prinston University physical anthropologist2 at the annual meeting of the American Association for the Advancement3 of Science in Boston on February 15.
Some thousands of years ago, there was a random4 mutation5. It suppressed the calcification6 of the third molar, a wisdom teeth. So many of you, and many of your children, have grown to adulthood7 without the apperance of third molars. Now that particular mutation has increased in frequency so that in some populations more than 40% people have one or more absent third molars. So you might ask the question: How did that develop because obviously you have an apparent third molar if you follow survival of the fetus8, then you are gonna fall over holding your mouth and dying in agony.
Reproduction of the fetuses9 – what is it all about? In other words, differential reproduction. How will this work? Well, one evening, a person, who has had serious chronic pain with impacted third molars, perhaps of lower third molar, impacting into the mandibular canal(下颌管), causing a lot of pain. The partner comes up and says: How about a bout10 of reproduction, dear? And the person says: Not tonight, dear, my jaws11 are killing12 me.
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1 chronic | |
adj.(疾病)长期未愈的,慢性的;极坏的 | |
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2 anthropologist | |
n.人类学家,人类学者 | |
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3 advancement | |
n.前进,促进,提升 | |
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4 random | |
adj.随机的;任意的;n.偶然的(或随便的)行动 | |
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5 mutation | |
n.变化,变异,转变 | |
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6 calcification | |
n.钙化 | |
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7 adulthood | |
n.成年,成人期 | |
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8 fetus | |
n.胎,胎儿 | |
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9 fetuses | |
n.胎,胎儿( fetus的名词复数 ) | |
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10 bout | |
n.侵袭,发作;一次(阵,回);拳击等比赛 | |
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11 jaws | |
n.口部;嘴 | |
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12 killing | |
n.巨额利润;突然赚大钱,发大财 | |
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13 scenario | |
n.剧本,脚本;概要 | |
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