15.The mystery of why humans are the only animals to have chins may have been solved by scientists who suggest that it is connected to the invention of cooking.
A paper from the University of Florida tries to explain exactly why humans-unlike all other primates-have chins.
A team led by Dr.James Pampush collected information from more than 100kinds of primate and compared it with historical information.Computer modelling found how the chin developed.
Random genetic change was ruled out because the chin developed 77times faster than the average genetic change.And the study finds no evidence that it served a useful purpose.The research,published in the Journal of Human Evolution,suggests the chin is a by-product of another event.In this case,the event could well be the invention of cooking.
"The chin began to appear as a result of major changes six million years earlier.The arrival of cooking and softer food meant humans no longer needed big teeth and powerful jaws,and over the next two million years to 200,000years both got smaller and the chin was born,"said Dr.Pampush."My guess is that it most likely happened around two million years ago when there was a jump in brain size.The changes which finally lead to the chin are directly related to cooking,and indirectly related to larger brains and bodies."
Dr.Pampush's new theory goes against previous suggestions that the chin was an example of sexual selection,with attractive chins marking out men who are likely to make good mates.The fact that both men and women have chins means the theory is unlikely.
Another theory put forward in the past said that the chin was a way to balance out the stress of chewing,but Dr.Pampush also threw doubt on that idea.
32.The reason why we have chinsB.
A.is connected to humans'action of chewing
B.has something to do with cooking
C.is random genetic change
D.is related to eating time.
33.How did the researchers get their result?D
A.By carrying out experiments.
B.By studying scientific theories.
C.By examining the human brain.
D.By comparing recorded information.
34.Before developing chins,humansA.
A.had bigger teeth
B.cooked softer food
C.had smaller jaws
D.had larger bodies
35.According to Dr.Pampush,the chin most probably appeared aroundC.
A.6million years ago.
B.4million years ago
C.2million years ago
D.0.2million years ago.
分析 本文講述了人類為什么有下巴.根據(jù)科學(xué)家的研究可知,人類有下巴與烹飪的發(fā)明有關(guān).
解答 BDAC
32.B.細(xì)節(jié)理解題.根據(jù)第一段中的it is connected to the invention of cooking 可知,人類有下巴與烹飪的發(fā)明有關(guān).
33.D.寫作手法題.根據(jù)第三段中的A team led by Dr James Pampush collected information from more than 100 kinds of primate and compared it with historical information 可知,研究 人員是通過數(shù)據(jù)比較得出的結(jié)果
100 kinds of pnmate and compared it with historical information 可知,研究 人員是通過數(shù)據(jù)比較得出的結(jié)果.
34.A.推理判斷題.根據(jù)倒數(shù)第三段中 的 The arrival of cooking and softer food meant humans no longer needed big teeth可以推斷,在下巴出現(xiàn)之前,人類的牙齒較大.
35.C.細(xì)節(jié)理解題.根據(jù)倒數(shù)第三段中 的 My guess is that it most likely happened around two million years ago 可命,Pampush博士認(rèn)為下E最可能 出現(xiàn)在約二百萬年前.
點(diǎn)評 閱讀理解題測試考生在閱讀基礎(chǔ)上的邏輯推理能力,要求考生根據(jù)文章所述事件的邏輯關(guān)系,對未說明的趨勢或結(jié)局作出合理的推斷;或根據(jù)作者所闡述的觀點(diǎn)理論,對文章未涉及的現(xiàn)象、事例給以解釋.考生首先要仔細(xì)閱讀短文,完整了解信息,準(zhǔn)確把握作者觀點(diǎn).