13．When we see men paying attention to their appearance，it's easy to assume that they're just trying to get partners．But our research on beards shows that beards probably evolved at least partly to help men strengthen their standing among other men．
Men and women on average look very different from each other-partly thanks to men's facial hair．And when we see differences between males and females，the explanation often boils down to evolution through sexual selection-the process that favours something that increases mating opportunities．
But interestingly，women don't seem that interested in beards．While some studies have found that women like a bit or even a lot of facial hair on men，other studies have reported that they prefer the clean-shaven look．The lack of consistent evidence means we can't conclude that beards evolved because women were attracted to them．
Researchers have therefore suggested that a second type of sexual selection may hold the answer．To reproduce，it's often not enough to simply be attractive．You also have to compete with the same sex for mating opportunities．The funny，shy guy at the back of the bar isn't going to stand a chance when competing with his aggressive brothers otherwise．And there's evidence that beards evolved to help men do just that．
In times with a greater proportion of single men competing for fewer women，beards and moustaches became more fashionable．A man's ability to grow a thick beard isn't actually neatly linked to his testosterone （男性荷尔蒙） levels．Despite this，a number of studies have suggested that both men and women regard men with beards as older，stronger and more aggressive than others．And dominant men can get more mating opportunities by frightening rivals to stand aside．
32．What makes men differ from women？D
A．Men's expressions．
B．Men's appearance．
C．Men's ability．
D．Men's facial hair．
33．According to the Researchers beardsC．
A．differ men from women
B．are preferred to be clean-shaven
C．help a man win sexual selection
D．make the shy guy stand behind the bar
34．What happened when there were more single men but fewer women？A
A．Beards were more popular．
B．Men were not aggressive．
C．More men could not get married．
D．People liked dominant men．
35．What do we learn about beards from the text？B
A．They are used to attract females．
B．They make men dominant．
C．They interest women．
D．They are not important now．
分析 本文属于说明文阅读，作者通过这篇文章主要向我们描述了一项关于男人的胡子的研究，胡子并不受女性的审美喜欢，但是它是男性成熟、强壮、和具有攻击性的象征，因此拥有浓密胡子的男性会占主导地位，获得更多的交配机会．
解答 32．D．细节理解题．根据文章第二段"Men and women on average look very different from each other-partly thanks to men's facial hair"男性和女性在外貌上有着很大区别，而这至少有一部分与男人浓密的面部毛发有关；故选D．
33．C．推理判断题．根据文章第三段"Researchers have therefore suggested that a second type of sexual selection may hold the answer"因此，研究人员提出了另一种性选择倾向，或许能解释这一现象，可推测胡子可以帮助男人赢得更多的性选择；故选C．
34．A．细节理解题．根据文章第四段"In times with a greater proportion of single men competing for fewer women，beards and moustaches became more fashionable"在男性比例远高于女性比例时，求偶时有胡须的男性就显得更为时尚，可知有胡须的男人更受欢迎；故选A．
35．B．推理判断题．根据文章最后一段"And dominant men can get more mating opportunities by frightening rivals to stand aside"那么占这种支配优势的人就能胁迫竞争对手靠边站，从而为自己赢得更多的交配机会，可知胡子可以使男人占据主导地位；故选B．
点评 考察学生的细节理解和推理判断能力，做细节理解题时一定要找到文章中的原句，和题干进行比较，再做出正确的选择．在做推理判断题不要以个人的主观想象代替文章的事实，要根据文章事实进行合乎逻辑的推理判断．
