問題詳情

Say “evolution” and some folks think of dusty archaeologists examining bone fragments.But, while evidence of previous life forms does play a central part in our understanding ofevolution, it is not necessary to go on a dig to see it in action—you might just look inside yourmouth.We all learn that human beings have thirty-two teeth. They are not all the same, though;the pointy incisors in the front are easily distinguished from the flatter, double-edged bicuspidsthat run along the side. Our teeth serve different functions: those incisors are great for bitingand holding on, while the bicuspids do more of a saw-motion for chewing.Now here is something you may not know: strictly speaking, it is not true that everyonehas thirty-two teeth. Even excluding people with dental problems, some folks have only thirty,or even twenty-eight. The ones that are missing are often the farthest back in the mouth. Wheredid they go?One likely answer is found in evolution. A long time ago—say ten thousand years—humanbeings ate much more raw meat. With a rough diet, you need lots of grinding teeth to helpprepare your food for digestion. Later, with the gradual advent of cooked foods, not all thoseteeth are needed anymore. If someone is born without them, he or she does not suffer any illconsequence; a scientist would say there is no evolutionary pressure to keep those teeth.Source: http://amos.indiana.edu/library/scripts/mouthevol.html
41. According to the passage, which of the following statements is true?
(A) Only archaeologists understand evolution.
(B) Everyone has thirty-two teeth.
(C) Ten thousand years ago, human beings ate much more raw meat than we do now.
(D) With the gradual advent of cooked foods, we need more teeth to chew them.

參考答案

答案：C
難度：適中0.676471
統計：A(2),B(3),C(23),D(5),E(0)

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