Are you a nice, well-rounded person, yet can’t seem to hit it off with the opposite sex? Maybe you need to embrace your dark side, according to a new study that shows people with certain extreme pathological personality traits fare well in the game of love.
In the study researchers focused on nearly 1,000 heterosexual men and women with a variety of pathological personality traits whose disorders ranged in severity from none to diagnosable. Participants were referred to the study by general practitioners or other medical professionals, says Fernando Gutiérrez at the Hospital Clinic of Barcelona, who led the research. Gutiérrez and his team inquired about participants’ lifetime numbers of mates and children, along with job level, income and other sociodemographic factors using a combination of self-reporting surveys and interviews.
Their results show that people with some pathological personality types, such as those considered neurotic and impulsive, had more mates and even more children than average, suggesting that such traits are not being weeded out by natural selection and actually may confer an evolutionary advantage.
The conclusions of the findings, published online in the October 23 Evolution & Human Behavior, are speculative due to study limits. For example, Corinna E. Löckenhoff, a human developmental psychologist at Cornell University who was not involved with the study, points to the possibility that there may be some biases in participants’ self-reports of relationship. “Respondents could have inflated the number of partners in an effort to depict themselves as more desirable. This may be especially true for individuals whose personality characteristics make them prone to dishonesty and for male respondents since cultural norms tend to view promiscuity [as] more favorable in men than in women,” she says. Additionally, it’s important “to make it clear that there is no ideal personality type and that variation in personality traits reflects a common phenomenon in the evolution of a wide range of anatomical, physiological and behavioral phenotypes,” adds says Alfonso Troisi, a research psychiatrist at the University of Rome Tor Vergata, also not involved with the study.
The study results show both males and females who were pathologically reckless and impetuous attracted more short-term partners than participants with average personalities. And obsessive-compulsive males—but not females—were successful at securing long-lasting mates, an outcome strongly associated with this group’s high income (obsessive-compulsives made nearly twice as much as the less obsessive study participants), Gutiérrez says.
The study results also revealed that neurotic females were more likely to be in lasting relationships. The most neurotic female participants had 34 percent more long-term mates and 73 percent more children than average despite exhibiting a trait typically associated with instability, anxiousness and insecurity, he explains.
According to Gutiérrez their results provide the first solid evidence that some personality disorders, rather than illnesses, could be sexually selected evolutionary strategies. “These strategies are supposed to be ancestral,” he says. “Some of them, such as impulsivity-boldness, probably predate humanity itself.”
But why would anyone marry and have children with people whose behaviors are outside the norm?
Gutiérrez says he once asked a patient why he married a neurotic woman. The man responded: “Me gusta por que es muy mujer” (I like her because she is “very woman”), an answer that may reveal a link between gender differences and stereotypes, says Löckenhoff. “The literature on gender differences suggests that, on average, women are slightly higher in neuroticism than men. Thus, some men could interpret high levels of negative emotionality in a mate as a sign of femininity,” she says. Further research, however, is needed to examine this possibility, she notes.
As for the impulsive and risk-takers—who were shown to have multiple short-term mates, Gutiérrez speculates that a number of people are attracted to those types because they are considered captivating. “While they are selfish, rule-breaking, imprudent and rebellious, they are also brave, temerarious, independent and self-reliant—and they live frantic, galvanizing lives,” he says. “This captivates many people. This desirability could also have an evolutionary basis,” Gutiérrez says, as this behavior could function as a fitness indicator, “…a signal that the subject has such good genetic quality and condition as to live dangerously without suffering harm,” he adds.
For obsessive personalities it is easy to find reasons for attraction, Gutiérrez says. “From a Darwinian viewpoint, money means survival, safeness and resources for the children. They are also serious, reliable and cautious,” he adds.
But another explanation may come from the observation that personality-wise, opposites do not necessarily attract, Löckenhoff says. “There is a well-known tendency to marry partners similar in personality to oneself. Thus, men who marry women who are at the extreme end of the neuroticism spectrum may be high in neuroticism themselves. The same could be true for other pathological personality characteristics,” she says.
Gutiérrez acknowledges that this aspect was not explored, so it remains possible that some of the participants have partners with similar personalities. But how would this help those with maladaptive personalities score more mates? Löckenhoff says that they may be good at fishing in a pool of potential partners who show similar—albeit less extreme—traits. Their future spouses may not realize the extent of the problem until they’re already committed to the relationship,” she says.
If such non-random mating is indeed occurring, Gutiérrez says their current findings would be even more disturbing. “If both parents are carriers of the pathological trait, it simply will be passed on to the progeny more vigorously,” he adds.
Other factors may also be at play. For instance, the itinerant lifestyles of impulsive people might put them in contact with a greater number of potential partners, Löckenhoff says, whereas women scoring high in neuroticism may turn to relationships in search of support. “Neurotic women may be more motivated to seek out stable relationships in order to gain emotional support and financial stability," she says.
Overall Gutiérrez says their findings support the less widespread view that the principles of evolution apply equally well to pathological personalities. “Some extreme traits are not as disadvantageous for fitness, as they appear to be for social adaptation or well-being, even when severely disordered subjects are examined,” he says. In fact, Gutiérrez thinks that as some traits increase in severity, they become more advantageous for attracting more mates and even producing more offspring. “This would characterize these traits as risky shortcuts to fitness, owing less to failures than to the twists and turns made by genes in order to perpetuate themselves,” he says.
But an important point to bear in mind is that “Within a given population, there exists a normal degree of genetic variation that may or may not make an individual more adapted to the environment or, more importantly, changes in the environment,” Troisi says.
This variation may also apply to personality traits. Much like genetic variations help species thrive in a changing environment, our different personalities may help us survive in our world. “Thus, to be different does not necessarily mean to be imperfect. Don’t rush to label abnormal any trait or behavior that is statistically deviant!” he adds.
Although thought-provoking, these results should be taken with a caveat, Löckenhoff cautions. “The findings are limited since they are drawn from patients in a single clinic, rely on self-reports of relationships instead of objective criteria and do not speak of the motivations or personalities of the relationship partners of the respondents,” she says.
Despite the uncertainties, you might fare better with that special someone if you allow the object of your affections to see a bit of your extreme side.