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 (男性荷爾蒙) 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.a(chǎn)re 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.