This curve is not limited to crime. The same age profile characterizes every quantifiable human behavior that is public (i.e., perceived by many potential mates) and costly (i.e., not affordable by all sexual competitors). 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.
Paul McCartney has not written a hit song in years, and now spends much of his time painting. Bill Gates is now a respectable businessman and philanthropist, and is no longer a computer whiz kid. J.D. Salinger now lives as a total recluse and has not published anything in more than three decades. Orson Welles was a mere 26 when he wrote, produced, directed, and starred in Citizen Kane.
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.
In the physical competition for mates, those who are competitive may act violently toward their male rivals. Men who are less inclined toward crime and violence may express their competitiveness through their creative activities.
The cost of competition, however, rises dramatically when a man has children, when his energies and resources are put to better use protecting and investing in them. The birth of the first child usually occurs several years after puberty because men need some time to accumulate sufficient resources and attain sufficient status to attract their first mate. There is therefore a gap of several years between the rapid rise in the benefits of competition and similarly rapid rise in its costs. Productivity rapidly declines in late adulthood as the costs of competition rise and cancel its benefits.
These calculations have been performed by natural and sexual selection, so to speak, which then equips male brains with a psychological mechanism to incline them to be increasingly competitive immediately after puberty and make them less competitive right after the birth of their first child. Men simply do not feel like acting violently, stealing, or conducting additional scientific experiments, or they just want to settle down after the birth of their child but they do not know exactly why.
The similarity between Bill Gates, Paul McCartney, and criminals—in fact, among all men throughout evolutionary history—points to an important concept in evolutionary biology: female choice.
Women often say no to men. Men have had to conquer foreign lands, win battles and wars, compose symphonies, author books, write sonnets, paint cathedral ceilings, make scientific discoveries, play in rock bands, and write new computer software in order to impress women so that they will agree to have sex with them. Men have built (and destroyed) civilization in order to impress women, so that they might say yes.
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.
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.
As a result, powerful men of high status throughout human history attained very high reproductive success, leaving a large number of offspring (legitimate and otherwise), while countless poor men died mateless and childless. Moulay Ismail the Bloodthirsty, the last Sharifian emperor of Morocco, stands out quantitatively, having left more offspring—1,042—than anyone else on record, but he was by no means qualitatively different from other powerful men, like Bill Clinton.