Why Do Beautiful Women Sometimes Marry Unattractive Men?

It may be that the unattractive man has a lot of money, or some other compelling attribute.

But a new study by Satoshi Kanazawa, an evolutionary psychologist at the London School of Economics, suggests it may be a simple supply-and-demand issue: there are more beautiful women in the world than there are handsome men.

Why? Kanazawa argues it’s because good-looking parents are 36% more likely to have a baby daughter as their first child than a baby son — which suggests, evolutionarily speaking, that beauty is a trait more valuable for women than for men. The study was conducted with data from 3,000 Americans, derived from the National Longitudinal Study of Adolescent Health, and was published in the Journal of Theoretical Biology.

According to this news article, “Selection pressure means when parents have traits they can pass on that are better for boys than for girls, they are more likely to have boys. Such traits include large size, strength and aggression, which might help a man compete for mates. On the other hand, parents with heritable traits that are more advantageous to girls are more likely to have daughters.”

Beauty is apparently just one “female” trait. Kanazawa has done previous research suggesting that nurses, social workers and kindergarten teachers — those with “empathic” traits — also had more daughters than sons. Meanwhile, he found that scientists, mathematicians and engineers are more likely to have sons than daughters.

It is good that Kanazawa is only a researcher and not, say, the president of Harvard. If he were, that last finding about scientists may have gotten him fired.

(Hat tip: Nadine Groney)


My theory is that every man and woman is somewhere on a single scale of masculinity vs femininity. Both sexes can be anywhere on this scale, though the sexes will manifest their position slightly differently -- e.g. masculine women tend to be strong-willed and career-minded, and feminine men tend to be sensitive and intellectual. Beautiful women, for cultural reasons, have long been encouraged by society and their female peers to mate with masculine (handsome, well-built) men, as that kind of man could hypothetically best provide for their offspring. However, in the modern world, it is the often the intellectual man (i.e., the helpful consultant or nerdy entrepreneur, rather than the burly manual worker) who is a more likely to be a better provider. So modern beautiful women (Marilyn Monroe was a good example) can sometimes be more attracted to a sensitive male. I also believe that the sex of a couple's child is determined mainly by where the father is on the masculinity/femininity scale -- the more masculine he is, the more likely Nature is to balance his blustering machismo with a girl, and the more feminine he is, the more likely Nature is to balance his neurotic sensitivity with a boy. For more on this, see the e-book 'The Twinkle Theory', which is a free download at http://www.onlineoriginals.com/showitem.asp?itemID=244



I have a dataset that apparently wasn't included in this study.

Over the course of my high school education, I asked out 27 physically attractive girls. 27 said no, and 0 said yes.

I think it goes some way in refuting the hypothesis.


Seems like a lot of readers are focusing on the concept of beauty and how to measure it. But when I went to the actual journal article, it became clear that for the past few years Kanazawa has been using a wide variety of indices beyond attractiveness scores to test a general hypothesis about evolution. (Thank you, Stephen, for linking to the journal to help us access the primary text.)

Here is that general hypothesis, articulated in the abstract of an earlier 2005 paper ("Big and tall parents have more sons: Further generalizations of the Trivers–Willard hypothesis"):

"This paper proposes the generalized Trivers–Willard hypothesis (gTWH), which suggests that parents who possess any heritable trait which increases male reproductive success at a greater rate than female reproductive success in a given environment will have a higher-than-expected offspring sex ratio, and parents who possess any heritable trait which increases female reproductive success at a greater rate than male reproductive success in a given environment will have a lower-than-expected offspring sex ratio. Since body size (height and weight) is a highly heritable trait which increases male (but not female) reproductive success, the paper hypothesizes that bigger and taller parents have more sons. The analysis of both surviving children and recent pregnancies among respondents of the National Child Development Survey and the British Cohort Survey largely supports the hypothesis."

Size and height are easier to measure than beauty, so the conclusions from the earlier size and height paper may satisfy more readers.



As long as the height is normalized for the Country of origin (definitions of "tall" vary, mostly by how recently the Country became industrialized and could full feed and house people - the so-called "secular trend"), then this study makes far more sense. So, why did they go from objective measure in that case to subjective measures of "beauty"?


I think the question of what is beauty goes to the reproducibility of the study. If beauty is truly in the "eye of the beholder" then how do you measure it? I prefer that study about size and gender selection. Also, since physical characteristics can be culturally advantageous does that influence which inheritable traits are passed on just by who you live among? That starts to sound suspiciously like Lysenkoism.


I definitely don't think there is an accurate way to gauge beauty absolutely. Hell the same person can rate someone two different ways based on mood, lighting, clothing, any number of things. Plus the female parent doesn't even influence sex biologically. It's the type of the SECOND sex chromosome that decides it, X or Y. How exactly can a beautiful mother change that. For that matter, I'm not entirely sure how a handsome male can change that. I hate to seem like I'm judging based only on preconceptions but all that is shown here is some correlation, and yet the study proposes a cause the mechanics of which go against biological fact.


Maybe they aren't truely attractive. You might not recognise them if you saw them first thingin the morning! The women know what they look like without the make up, hairstyling, enhancing undergarments, and enhancing surgery.....maybe they see an outward match that we don't. Sometimes the gentleman that might seem unattractive outwardly more than makes up for it in personality and how he will treat a woman. Looks are more unstable than a match of interests and personalities.


It could be that human beings are conditioned to be more likely to think of women as beautiful, than to think of men as handsome. There is no "fact" that there are more of the one than the other, just the bias.


Any good looking guy knows that women favor ugly men. It is a mystery, just like every single action that most females undertake. Maybe its about their low self esteem, since all good looking women have low self esteem, just look at the supreme arrogance they display, that is really a sign of an inferiority complex. Maybe its about controlling some ugly loser and spending all his cash and treating him like dirt. Maybe its just because they are irrational and there is no answer. I have a great personality, but, I get turned down for some ugly jerk who treats them like a piece of meat, and I am told its because of personality. Women make this judgment on looks alone, they are intimdated of a good looking guy and assume he is a jerk because he won't bow before them, and they mainly just intimidated since their whole world is based on the supreme superficiality of the reflection they see as they put on their make up. They profit from their looks, exercising a level of power that is so potent and omnipresent that most people do not even see its existence. They primp and priss and strut around like gods, holding a man's self esteem in the palm of their hand, which they are only to glad to crush to make themselves feel better. The good looking guy pays a dear price for daring to compete with her in her area. All of the good looking guys that I know get less women than unattractive guys, its an obvious fact, and completely unfair. I say they are insane and thats that. Don't try to figure them out.



Lol...I always wonder why the cliche goes that good looking women favor unattractive men.My initial attractions are always toward the good looking ones (and Im a woman).It takes a few interactions with the not so good looking ones to then get to like their good personality traits.


I think that if "mating" means more than one-night stand or just casual sex, physical attractiveness (does not matter how you measure it - by facial symmetry or hip/waist ratio) will be secondary to other personal qualities, hence the answer for classical "beauty and the beast" riddle.

Do biologists have an answer or at least a hypothesis on why particular couple has a girl or a boy? Possibly it makes more sense to study their ideas first?


ng, I think I love you


what you are saying proves my point: women turn down the good looking guy for one reason: because he's good looking. They don't get to know him and his personality, they automatically assume, no matter what, that he does not have a good personality, and that the ugly guy does, why, because he must, because he's ugly, because we all know that all good looking guys are bad people, and ugly guys are all saints, they all wash the feet of the poor in Calcutta, and they are all beyond judgment. This is a totally superficial judgment, it assumes that all good looking guys are the same. well, what about all stuck up blondes with their nose in the air and their face in a mirror, with a shirt that says princess, and a license plate that says 2Hot4U, who is always going around asking her adoring audience: "do you think I could be a model?" At the same time she ignores and rejects the good looking guy for daring to have the self esteem to know he is good looking, but turning him down because he wasn't "confident" like the ugly guy who has nothing to lose; and turning him down for his "prsonality" when the guy she chooses is an ugly jerk who is mean to her and cheats on her, and turns the good looking guy down because he is really just too nice. Most of these ugly guys out here getting these beautiful women do it for two reasons: most beautiful women like a jerk, and most beautiful women like an ugly guy because of a self esteem issue. There are exceptions, as we have seen above, as with anything, there are many great women who make perfect sense, but there are many who don't. I will admit, when I look at the typical guy out here that is highly successful with these types of women, I can't imagine why anybody would want anything to do with any guy, since they are such arrogant jerks. Another thing, good looks are not just about sex. I get pleasure just from being around good looking women. How can you kiss someone ugly. Also, I am straight, but if I am talking to a guy, I would rather he not be ugly. If I am at a concert, I would rather look at Chris Cornell than somone ugly like Kid Rock. If I am watching a movie, I would rather see someone who looked like George Clooney rather than Billy Bob Thorton. Just like when I have a car, I would rather it be a good looking car. I would rather live in a nice looking house. I would rather my meal be served to me in an aesthetically pleasing manner. And, I would rather the trees, the sky, and the lillies in the field be attractive rather than not. Call me crazy.



This study is wierd, since it implies that guys (like me) can selectively spurt out sperms based on the genes that they have. Hmmm, how do I do this? While this is great news for people in China, who has strong preference toward boys (there's you're answer, Chairman Mao! If you want boys, get your boys to be nerdy, and then make them marry unattractive girls!), I guess I need to practice my butt-clenching skills to make this work.

There is a lot of folklore about how to selectively have boy/girl babies. In Japan, it is said that pre-mature ejaculation leads to girl babies (due to the ph level within the vagina that tends to kill sperms with XY chromosomes), and proper female orgasm leads to boys. This is a stupid theory, but this may be a mechanism to explain this experiment; with attractive women, guys may get more aroused then they thought, leading to pre-mature ejaculation, and thus leading to more girls. This also explains why this is only observed in the first-borns; by the time they get to the second baby, you've seen enough of her so you won't have to rush.

Mayby Dr. Kanazawa had this folk theory in mind when he was doing this study.


Bruce Hayden

I think that a couple of things are going on here. First, and foremost, attractiveness as a mate has traditionally varied greatly between the two sexes. In the case of males, a lot of it ultimately comes down to the guy's ability to provide resources. In some societies, that implies size, but not all, and not ours now. Mathematical thinking is presumably more useful that size now.

Also, there does seem to be an conflict between really good looking men and women. From both, you hear about the arrogance of the other. So, maybe many relationships have space for just one such ego.

But what is really interesting about the study is the theory that inheritable traits that benefit boys would result in more boys, and visa versa. It makes sense that it might be accurate.


Do beautiful women marry unarrractive men because all the beautiful men are gay?

Bruce Hayden

I would suggest that one big reason that beautiful women marry unattractive men is that their criteria for a mate is different than a man's criteria. Many women are more likely to go for wealth and power, than looks, and those are only slighly correlated with looks (apparently, good looking men are slightly more successful than less attractive men, given equivalent credentials).

Bruce Hayden

I haven't seen any statistics on this, but do believe through observation that gay men do take significantly more care in their grooming, on average, and, thus, do look better, given what they are working with.

However, a recent study also showed that gay men on average have slighly narrower shoulders and slighter frames than straight men, and to the extent that broad shoulders and heavier frame translate into good looks, that would somewhat counter their better grooming.


There's something missing here. The idea behind this is that evolutionary pressure means parents are more likely to have a kid of x gender because that gender is more likely to benefit from the traits they possess. Hence hot people having girls and brainiacs having boys.

But the reason hot people have girls is that women are generally more highly valued based on their looks than guys. Which directly say that women are more likely than their male counterparts to find things other than looks attractive in a potential partner. If that wasn't the case, the selection pressure wouldn't be happening in the first place because there'd be no greater benefit in being a hot woman as opposed to a hot guy. Which is very different from a supply and demand issue, it's just different attraction criteria.


A while back I came upon this study:

which stated that handsome men are prefered by woemn and that status playes no part in female mating selection. If this is accurate (it does seem to fly in the face of common knowledge by all the comments expect mine agree, and female reader wrote duh!) then beauty is not a "female trait". In fact, if anything, this article seems to indicate that beaty is more usefull to men than to women.


Sex differences among preferences for good looking and high-status partners were small or even insignificant. [...] In both sexes, PA [Physical attractiveness]was much more preferred in a potential partner than status. For both sexes, physical appearance was decisive for the subject's dating attractiveness. [...]Men with more than four sexual partners were all above-average in PA, while the most attractive women had a medium number of sexual partners.