A new study conducted by researchers in Australia shows that women prefer men with heavy stubble over clean-shaven guys and guys sporting light stubble or full beards。澳大利亚一项最新研究显示，相比把胡子刮得干干净净、或者只留着一点胡子茬、或者满脸大胡子的男性，女性更青睐留着浓密短胡茬的男人。

And what sort of men's facial hair do straight guys think is preferable among their peers? In the study, published in the May issue of the journal Evolution & Human Behavior, full beards and heavy stubble edged out light stubble and the clean-shaven look。那么男性是如何看待留胡子的同胞呢？研究显示，男性同样认为有大胡子或重胡茬的要比没胡子或只有一点胡茬的面孔更具吸引力。这一研究发表在五月《进化与人类行为》期刊上。

For their research, University of New South Wales professors Barnaby J. Dixson and Rob C. Brooks¹ presented photos of 10 smiling men to 177 heterosexual men and 351 women, according to MedicalXpress. Each man in the photos was shown in four ways -- clean-shaven, with five days of beard growth （light stubble）， 10 days of growth （heavy stubble）， and with a full beard。据MedicalXpress网站报道，新南威尔士大学巴纳比·迪克森教授和罗伯·布鲁克斯教授进行了这项研究。他们让177名异性恋男性和351名女性观看10名微笑男子的照片，这10个人各有四张照片，分别是：刚刚刮好胡子的、五天没刮胡子的（只有一点胡子茬）、十天没刮胡子的（重胡茬）和满脸大胡子的。

The researchers then asked the women and men to rate the men in the photos according to their attractiveness, finding heavy stubble to be the clear winner among women。研究人员随后让所有测试者按照相片中男子的吸引力大小为这几张相片排序，结果发现有重胡茬的男性更受女性青睐。

What explains the hankering for heavy stubble?为什么会是这个结果呢？

“Our findings confirm that beardedness affects judgments² of male socio-sexual attributes and suggest that an intermediatelevel of beardedness is most attractive while full-bearded men may be perceived as better fathers who could protect and invest in offspring,” the researchers concluded in the abstract of their study。研究人员总结道：“我们的研究证实，留什么样的胡子的确会影响到人们对男性社会属性的判断。留中等程度胡子的男性是最具魅力的，而蓄着大胡子的男性则会被认为是更尽责的父亲，能承担起保护、教育子女的重任。”

Dixson and Brooks hypothesize that facial hair makes men seem more mature and masculine but also more dominant³ and aggressive, the website of the Australia edition of Men's Health reported. “Men, judging other men, might be sensitive to the overall level of masculine threat and aggression⁴ signaled through full beards,” the researchers wrote, according to the website. “Women, by contrast, may balance…a competitive masculine partner against the costs of mating with a too-masculine partner.”迪克森和布鲁克斯推测，胡子不仅可以使男性看起来更成熟、更具男子气概，还更有闯劲儿和支配力。研究者在澳大利亚“男性健康”网站写道：“男性评价男性时，会注意对方整体的阳刚气概，这种威胁攻击性都能从他的从大胡子里看出来；而女性在评价男性时，则会更均衡全面，她们更愿意和一个相对阳刚、而非那种过于男子气概的人在一起。”

As to why light stubble loses out to heavy stubble, the researchers believe that there's “a threshold of density⁵ and distribution may be necessary for beards to function as an attractive signal,” Science magazine reported. In other words, it's just too patchy。那为什么只有一点儿胡茬的人不如留有重胡茬的人更具魅力呢？研究人员解释说，“胡子作为展现性感的标志，也存在着一个密度分布阈值”。简而言之，只有一点胡茬的话看着太零碎了。