Why Beautiful People Have More Daughters: From Dating, Shopping, and Praying to Going to War and Becoming a Billionaire–Two Evolutionary Psychologists Explain Why We Do What We Do (17 page)

The comedian Bill Maher captures the essence of female choice perfectly, when he quips: “For a man to walk into a bar and have his choice of any woman he wants, he would have to be the ruler of the world. For a woman to have the same power over men, she'd have to do her hair.” In other words, any reasonably attractive young woman exercises as much power as does the (male) ruler of the world.

Q. Why Does Marriage “Settle” Men Down?

There is something else that crime and genius have in common. (See “What Do Bill Gates and Paul McCartney Have in Common with Criminals?” above.) Just as age does,
marriage depresses both tendencies.

Criminologists have long known that criminals tend to “settle down” and desist (stop committing crime) once they get married, while unmarried criminals continue their criminal careers. But criminologists tend to explain this phenomenon from the social control perspective
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pioneered by the criminologist Travis Hirschi
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(the same Hirschi of the team who first discovered the age-crime curve). Social control theorists argue that marriage creates a bond to the conventional society, and investment in this bond, in the form of a strong marriage, makes it less likely that the criminal would want to remain in the criminal career, which is incompatible with the conventional life. Men must therefore desist from crime when they get married in order to protect their investment in conventional life; in Hirschi's language, married men develop a “stake in conformity.”
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Marriage also increases the scope and efficiency of social control on the criminal. Now there is someone living in the same house and monitoring the criminal's behavior at all times. It would be more difficult for the criminal to escape the wife's watchful eye and engage in illicit activities.

The social control explanation for the effect of marriage on desistance from crime makes perfect sense,
until
one realizes that marriage has the same desistance effect on perfectly legal, conventional activities, such as science. A comparison of the “age-genius curve” among scientists who were married at some point in their lives with the same curve among those who never married shows the strong desistance effect of marriage on scientific productivity. Half as many (50.0 percent) unmarried scientists make their greatest contributions in their late 50s as they do in their late 20s. The corresponding percentage among the married scientists is 4.2 percent. The mean age of peak productivity among the unmarried scientists (39.9) is significantly later than the mean peak age among married scientists (33.9).
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Given that the Nobel Prize for scientific achievement didn't exist in the ancestral environment, the evolved psychological mechanisms of men appear to be rather precisely tuned to marriage as a cue to desistance. Nearly a quarter (23.4 percent) of all married scientists make their greatest scientific contribution in their career and then desist within five years after their marriage. The mean
delay
(the difference between their marriage and their peak productivity) is a mere 2.6 years; the median is 3.0 years. It therefore appears that scientists rather quickly desist after marriage, while unmarried scientists continue to do important scientific work. When you remember that great scientific discoveries usually require many years of cumulative and continued research, the near coincidence of the male scientists' marriages and their desistance (after which they cease to make any greater scientific discoveries) is remarkable. A study by the sociologists Lowell L. Hargens, James C. McCann, and Barbara F. Reskin also demonstrates that childless research chemists are more productive than those with children.
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You may think that unmarried scientists continue to make scientific contributions much later in their lives because they have more time to devote to their careers. Unmarried and therefore childless scientists do not have to spend time taking care of their children, driving them back and forth between soccer practices and ballet lessons, or doing half the house hold chores, and that is why unmarried scientists can continue making great contributions to science while married scientists must desist to devote their time to their families. This is precisely Hargens et al.'s interpretation of the negative correlation between parenthood and productivity among research chemists.

But we would point out that almost all the scientists in the main data on scientific biographies we rely on above lived in the eighteenth and nineteenth centuries, when married men made very little contribution in the domestic sphere and their wives did not have their own careers. Hargens et al.'s data come from 1969–70, when this was probably still true to a large extent. We would therefore suggest that, if anything, married scientists probably had
more
(rather than less) time to devote to science, because they had someone to take care of their domestic needs at all times.

Why, then, does marriage depress the productivity of all men, criminals, and scientists alike? What underlies the desistance effect of marriage?

Enjoying the Fruits of Their Labor

The social control perspective on the desistance effect of marriage is at best incomplete if marriage has the same desistance effect on scientists. Unlike criminal behavior, scientific activities are completely within conventional society and are thus not at all incompatible with marriage and other strong bonds to conventional society. Unlike criminals, scientists are not subject to social control (by their wives or others), since scientific activities are not illegal or deviant in any way.

We believe an evolutionary psychological theory provides a much simpler explanation for the desistance effect of marriage for both crime and science, in the form of a single psychological mechanism that predisposes young men to compete and excel early in their adulthood but subsequently turns off after the birth of their children (which quickly followed pair-bonding and regular sex in the absence of reliable means of birth control in the ancestral environment). After their marriage and children, male scientists do not
feel like
spending hours and hours in their labs, just like married criminals do not
feel like
taking great risks and committing crimes. But neither scientists nor criminals know why.

From the evolutionary psychological perspective, reproductive success is the end, and everything men do (be it crime or scientific research) is but a means to this ultimate end. From this perspective, the question of why marriage depresses crime and scientific productivity misses the whole point. Does it make sense for men to continue employing the means even after they have achieved the ends they were trying to attain with the means? This is why married men are less likely to engage in a whole range of risk-taking behaviors, like driving fast, which are designed indirectly and unconsciously to attract women. Indeed, automobile insurance statistics clearly show that married men have fewer car accidents.

Q. Why Do Some Men Beat Up Their Wives and Girlfriends?

Critics of evolutionary psychology often claim that evolutionary psychological explanations are “untestable” and “unfalsifiable.”
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As but one perfect example of eminent testability and falsifiability of evolutionary psychological explanations
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we offer two competing explanations of domestic violence, formulated by the two deans of modern evolutionary psychology (who happen to be married to each other, no less).

When Martin Daly and Margo Wilson began studying domestic violence and uxoricide (the killing of one's wife) in the early 1980s, they had competing explanations.
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Daly hypothesized that domestic violence and uxoricide resulted when the husband did not value his wife sufficiently and mistreated her as a result. Since a wife's fertility and reproductive value decline with age, Daly predicted that older wives were at a greater risk of spousal abuse and homicide than younger wives. Wilson, in contrast, hypothesized that domestic violence and uxoricide were a maladaptive byproduct of the husband's inclination and tendency to guard his wife to make sure that she did not have sexual contact with other men. Because men should be more motivated to guard younger, more valuable wives, Wilson predicted that younger wives were at a greater risk of spousal abuse and homicide than older wives.

Both explanations use impeccable evolutionary psychological logic and derive from known facts, but both predictions could not be true simultaneously. So Daly and Wilson got to work as the good scientists that they are, collecting data on domestic violence and uxoricide in Canada and the United States, and putting the two competing predictions to the empirical test. Their data showed that younger wives were at a much greater risk of violence and murder than older wives. In the end, Wilson's prediction turns out to be true, and Daly's false.
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Is evolutionary psychology untestable and unfalsifiable?

Astute readers may be thinking right now, “But younger women are usually married to younger men. And younger men are more violent than older men, as you point out in your discussion of the age-crime curve (see “What Do Bill Gates and Paul McCartney Have in Common with Criminals?” above). So younger women are at a greater risk of spousal abuse and murder, not because they are young but because their husbands are young and therefore more violent.”

Close, but no cigar. While it is difficult to separate the effects of the husband's age and the wife's age, careful statistical analyses show that the wife's age almost entirely determines the likelihood of being a victim of spousal abuse and homicide. Middle-aged husbands (ages 45–54) legally married in Canada to much younger wives (ages 15–24) are
more than six times
as likely to kill their wives than young husbands (ages 15–24) married to women of similar age.
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Among common-law marriages, middle-aged husbands married to much younger wives are
more than 45 times
as likely to kill their wives as young husbands.
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The effect of the wife's age is so powerful that it overrides and even reverses a man's tendency to become less violent with age.
Thus, while it is true that younger men in general are much more violent and commit more murders than older men, young and old men kill different types of people. Young men kill other men (their male sexual rivals); older men kill their wives. As a result, the proportion of men among murder victims declines as the murderer's age increases. For murderers aged 15–19, 86.3 percent of the victims are males; for murderers aged 65–69, only 51.4 percent of them are males.
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An Adaptation Gone Awry

From the evolutionary psychological perspective, spousal abuse is an extreme, maladaptive, and largely unintended consequence of a man's desire for mate-guarding. Because of the possibility of cuckoldry (unwittingly investing in someone else's genetic offspring), men are strongly motivated to guard their mates to make sure that they do not have sexual access to other men. And they use any means, including intimidation and violence, to achieve this goal.
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Unfortunately, sometimes their adaptive strategy of mate-guarding goes too far and results in a maladaptive outcome of spousal abuse and even murder. Because young women are reproductively more valuable than older women, men are more motivated to protect and guard their younger wives than their older wives, with the unfortunate consequence that younger wives are at a greater risk of spousal abuse than older wives. This is why it is the wife's age, not the husband's, that predicts the likelihood of spousal abuse and murder. Even though a 50-year-old man is typically much less violent and criminal than a 25-year-old man, a 50-year-old man married to a 25-year-old woman is much more likely to abuse and murder his wife than a 25-year-old man married to a 50-year-old woman (although there are very few such couples) or even a 25-year-old man married to a 25-year-old woman.
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