from http://www.psychologytoday.com/articles/pto-20070622-000002.xml
Human nature is one of those things that everybody talks about but no one can define precisely. Every time we fall in love, fight with our spouse, get upset about the influx of immigrants into our country, or go to church, we are, in part, behaving as a human animal with our own unique evolved nature—human nature.
This means two things. First, our thoughts, feelings, and behavior are produced not only by our individual experiences and environment in our own lifetime but also by what happened to our ancestors millions of years ago. Second, our thoughts, feelings, and behavior are shared, to a large extent, by all men or women, despite seemingly large cultural differences.
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Let's make a long story short, here are ten pieces of truth about human nature. (I cut out some details)
Adapted from Why Beautiful People Have More Daughters, by Alan S. Miller and Satoshi Kanazawa, to be published by Perigee in September 2007
1. Men like blond bombshells (and women want to look like them)
Women's desire to look like Barbie—young with small waist, large breasts, long blond hair, and blue eyes—is a direct, realistic, and sensible response to the desire of men to mate with women who look like her. There is evolutionary logic behind each of these features.
2.Humans are naturally polygamous
The history of western civilization aside, humans are naturally polygamous. Polyandry (a marriage of one woman to many men) is very rare, but polygyny (the marriage of one man to many women) is widely practiced in human societies, even though Judeo-Christian traditions hold that monogamy is the only natural form of marriage. We know that humans have been polygynous throughout most of history because men are taller than women.
Among primate and nonprimate species, the degree of polygyny highly correlates with the degree to which males of a species are larger than females. The more polygynous the species, the greater the size disparity between the sexes. Typically, human males are 10 percent taller and 20 percent heavier than females. This suggests that, throughout history, humans have been mildly polygynous.
...In societies where rich men are much richer than poor men, women (and their children) are better off sharing the few wealthy men; one-half, one-quarter, or even one-tenth of a wealthy man is still better than an entire poor man. As George Bernard Shaw puts it, "The maternal instinct leads a woman to prefer a tenth share in a first-rate man to the exclusive possession of a third-rate one." Despite the fact that humans are naturally polygynous, most industrial societies are monogamous because men tend to be more or less equal in their resources compared with their ancestors in medieval times.
3. Most women benefit from polygyny, while most men benefit from monogamy
When there is resource inequality among men—the case in every human society—most women benefit from polygyny: women can share a wealthy man. Under monogamy, they are stuck with marrying a poorer man.
The only exceptions are extremely desirable women. Under monogamy, they can monopolize the wealthiest men; under polygyny, they must share the men with other, less desirable women. However, the situation is exactly opposite for men. Monogamy guarantees that every man can find a wife. True, less desirable men can marry only less desirable women, but that's much better than not marrying anyone at all.
Men in monogamous societies imagine they would be better off under polygyny. What they don't realize is that, for most men who are not extremely desirable, polygyny means no wife at all, or, if they are lucky, a wife who is much less desirable than one they could get under monogamy.
4.Most suicide bombers are Muslim
Suicide missions are not always religiously motivated, but according to Oxford University sociologist Diego Gambetta, editor of Making Sense of Suicide Missions, when religion is involved, the attackers are always Muslim. Why? The surprising answer is that Muslim suicide bombing has nothing to do with Islam or the Quran (except for two lines). It has a lot to do with sex, or, in this case, the absence of sex.
What distinguishes Islam from other major religions is that it tolerates polygyny. By allowing some men to monopolize all women and altogether excluding many men from reproductive opportunities, polygyny creates shortages of available women. If 50 percent of men have two wives each, then the other 50 percent don't get any wives at all.
The other key ingredient is the promise of 72 virgins waiting in heaven for any martyr in Islam. The prospect of exclusive access to virgins may not be so appealing to anyone who has even one mate on earth, which strict monogamy virtually guarantees. However, the prospect is quite appealing to anyone who faces the bleak reality on earth of being a complete reproductive loser.
It is the combination of polygyny and the promise of a large harem of virgins in heaven that motivates many young Muslim men to commit suicide bombings.
5.Having sons reduces the likelihood of divorce
6.Beautiful people have more daughters
7.What Bill Gates and Paul McCartney have in common with criminals
For nearly a quarter of a century, criminologists have known about the "age-crime curve." In every society at all historical times, the tendency to commit crimes and other risk-taking behavior rapidly increases in early adolescence, peaks in late adolescence and early adulthood, rapidly decreases throughout the 20s and 30s, and levels off in middle age. This curve is not limited to crime. The relationship between age and productivity among male jazz musicians, male painters, male writers, and male scientists—which might be called the "age-genius curve"—is essentially the same as the age-crime curve. Their productivity—the expressions of their genius—quickly peaks in early adulthood, and then equally quickly declines throughout adulthood. The age-genius curve among their female counterparts is much less pronounced; it does not peak or vary as much as a function of age.
A single theory can explain the productivity of both creative geniuses and criminals over the life course: Both crime and genius are expressions of young men's competitive desires, whose ultimate function in the ancestral environment would have been to increase reproductive success.
8.The midlife crisis is a myth—sort of
Many believe that men go through a midlife crisis when they are in middle age. Not quite. Many middle-aged men do go through midlife crises, but it's not because they are middle-aged. It's because their wives are.
From the evolutionary psychological perspective, a man's midlife crisis is precipitated by his wife's imminent menopause and end of her reproductive career, and thus his renewed need to attract younger women. Accordingly, a 50-year-old man married to a 25-year-old woman would not go through a midlife crisis, while a 25-year-old man married to a 50-year-old woman would, just like a more typical 50-year-old man married to a 50-year-old woman. It's not his midlife that matters; it's hers. When he buys a shiny-red sports car, he's not trying to regain his youth; he's trying to attract young women to replace his menopausal wife by trumpeting his flash and cash.
9.It's natural for politicians to risk everything for an affair (but only if they're male)
On the morning of January 21, 1998, as Americans woke up to the stunning allegation that President Bill Clinton had had an affair with a 24-year-old White House intern, Darwinian historian Laura L. Betzig thought, "I told you so." Betzig points out that while powerful men throughout Western history have married monogamously (only one legal wife at a time), they have always mated polygynously (they had lovers, concubines, and female slaves). With their wives, they produced legitimate heirs; with the others, they produced bastards. Genes make no distinction between the two categories of children. ...
10.Men sexually harass women because they are not sexist
An unfortunate consequence of the ever-growing number of women joining the labor force and working side by side with men is the increasing number of sexual harassment cases. Why must sexual harassment be a necessary consequence of the sexual integration of the workplace?
Studies demonstrate unequivocally that men are far more interested in short-term casual sex than women. In one now-classic study, 75 percent of undergraduate men approached by an attractive female stranger agreed to have sex with her; none of the women approached by an attractive male stranger did. Many men who would not date the stranger nonetheless agreed to have sex with her.
Studies demonstrate unequivocally that men are far more interested in short-term casual sex than women. In one now-classic study, 75 percent of undergraduate men approached by an attractive female stranger agreed to have sex with her; none of the women approached by an attractive male stranger did. Many men who would not date the stranger nonetheless agreed to have sex with her.
The quid pro quo types of harassment are manifestations of men's greater desire for short-term casual sex and their willingness to use any available means to achieve that goal. Feminists often claim that sexual harassment is "not about sex but about power;" Browne contends it is both—men using power to get sex. "To say that it is only about power makes no more sense than saying that bank robbery is only about guns, not about money."
Sexual harassment cases of the hostile-environment variety result from sex differences in what men and women perceive as "overly sexual" or "hostile" behavior. Many women legitimately complain that they have been subjected to abusive, intimidating, and degrading treatment by their male coworkers. Browne points out that long before women entered the labor force, men subjected each other to such abusive, intimidating, and degrading treatment.
Abuse, intimidation, and degradation are all part of men's repertoire of tactics employed in competitive situations. In other words, men are not treating women differently from men—the definition of discrimination, under which sexual harassment legally falls—but the opposite: Men harass women precisely because they are not discriminating between men and women.