Why Women Have Sex (3 page)

In intrasexual competition the qualities that lead to access to more desirable mates get passed on in greater numbers because the victors mate
more successfully and produce more or higher quality offspring. The characteristics that commonly lead to loss in these competitions bite the evolutionary dust, since they are passed on in fewer offspring. Although this process is sometimes easier to see in males, for whom competition is often ostentatious, the same logic applies to females, for whom competition is generally more subtle. Among humans, for example, social reputation is a key component of same-sex competition. Social reputation is often gained or lost through subtle verbal signals, gossip, alliance formation, and other tactics that sometimes fly under the radar. Evolution—which simply means change over time—occurs as a consequence of same-sex competition because the victors have greater access to desirable sex partners.

Preferential mate choice, on the other hand, involves desiring qualities in a mate that ultimately lead to greater reproductive success for the chooser. Women who choose to have sex with healthy men, for example, gain reproductive advantages over women who choose to have sex with disease-ridden men. Women remain healthier themselves, since they do not pick up the man’s communicable diseases. Their children remain healthier, since they too avoid picking up the man’s diseases through close contact. And if the qualities linked to health are partly heritable, as we now know they are, then the women’s children will inherit genes for good health. Women’s mating desires and the qualities they find sexually attractive have evolved because they led ancestral mothers to make wise choices, both in sex partners and in long-term mates.

Evolved psychological mechanisms go far beyond reproduction to include women’s sexual desires, patterns of sexual attraction, mate preferences, the emergence of the emotion of love, sexual jealousy, and much more. Each major component of women’s sexual psychology solves an adaptive problem, providing a specific benefit to women—or more precisely, provided a benefit to ancestral women that modern women have inherited. So when evolutionary psychologists use phrases such as “evolved psychological mechanisms” or “psychological adaptations,” they do not mean rigid, robotlike instincts expressed in behavior regardless of circumstances. Rather, human psychological adaptations are extremely flexible, highly sensitive to circumstance, and activated only in some social contexts. An evolved emotion such as sexual jealousy, for
example, might motivate a woman to have sex with her partner to keep his mind off other women. But a woman usually experiences sexual jealousy only if there is a sexual threat to her relationship.

Moreover, a woman might deal with a sexual threat in a multitude of other ways, such as increased vigilance or an increased outpouring of love. Even when women’s sexual adaptations are activated, it does not mean that they must invariably act on them. A woman’s sexual desire, for instance, might be activated by a chance encounter with a tall, dark, and handsome stranger, but she may choose not to act on that evolved desire due to a wish to remain loyal to her regular partner, a concern about damage to her reputation, or moral or religious convictions. Psychological adaptations are not inflexible instincts that ineluctably get expressed in behavior, but rather are flexible mechanisms whose expression is highly contingent on context.

Over the past twenty years, the Buss Evolutionary Psychology Lab has used a variety of research methods to explore human sexual psychology. The methods range from observational studies of women’s tactics of sexual attraction in singles bars to physiological recordings to imagining a romantic partner having sexual intercourse with someone else. They include self-reports of sexual mate poaching; experimental studies of women’s sexual attraction to aspects of men’s physique; and hormonal assays of the effects of ovulation on women’s sexual desire. Samples include college undergraduates, dating couples, newlywed couples, older couples, and a culturally diverse sample of more than ten thousand individuals from thirty-three countries worldwide. The Buss Lab has studied the dangerous passion of sexual jealousy, why women have affairs, parental tactics to constrain the sexuality of their daughters, the evolution of love, sexual deception, the effects of ovulation on women’s sexuality, whether men and women can be “just friends,” personality predictors of sexual satisfaction, cues that foretell a partner’s affair, derogation and gossip about sexual competitors, and “sexual intelligence.”

The notion that many components of women’s sexual psychology have an evolutionary function does not imply that all features are adaptive, or that every woman’s sexual behavior serves a benefit. Quite the contrary. As we will see throughout this book, some reasons that propel women into sexual encounters are self-destructive and cause personal
problems, the loss of self-esteem, and even life tragedies. Some reach clinical proportions and develop into distressing sexual disorders. We cover the entire range of women’s sexual psychology, from the lows of sexual disorders and how they can be treated to the highs of attaining and maintaining a fulfilling sexual life.

Our new and never-before-reported study of why women have sex was conducted online between June 2006 and April 2009. Web links and online classified advertisements requested women’s participation in a study designed to understand sexual motivations. The survey itself was hosted by a database using 128-bit encryption technology to protect the information from hackers and to ensure the utmost anonymity to the study’s participants. The women who participated first completed an informed consent during which they received full disclosure of the survey’s subject matter and were assured that they could discontinue the survey at any time. We have shared the women’s exact words, after eliminating any details that might identify them to maintain the confidentiality of their responses. We also let the participants know that if they had any concerns about the study or became distressed after answering the questions or sharing their stories, a clinical psychologist would be available to discuss their concerns with them.

The survey began by asking the women if they had ever had sex for one of the 237 reasons we identified in our original study. If a woman’s answer was yes, she would then be prompted to describe a specific experience; if no, she was asked about another reason for having sex. The women’s answers confirmed, enhanced, and enriched the quantitative findings of our initial investigation of why humans have sex. Most important, they gave real women an opportunity to explain in their own words their motivations for having sex, providing a depth of insight into sexual psychology beyond what could be captured from statistical analysis.

In the course of the study, 1,006 women from a variety of backgrounds shared their experiences with us. They hailed from forty-six of the fifty states (all except Alaska, Montana, Nebraska, and Delaware); eight of the ten provinces of Canada (all but Saskatchewan and Prince Edward Island) and one of the two territories (Northwest Territory); three European
countries (Germany, Belgium, and France); and Australia, New Zealand, Israel, and China. The women ranged in age from eighteen (the youngest we accepted into the study) to eighty-six and identified ethnically as American Indian, Asian, black, white (non-Hispanic), and Latino. About 57 percent considered themselves to be part of a specific religious tradition—Christian (Anglican, Baptist, Catholic, Episcopalian, Lutheran, Methodist, Mormon, Pentecostal, Protestant, and Seventh Day Adventists), Jewish, Muslim, Buddhist, Hindu, Taoist, Unitarian Universalist, and pagan or Wicca—while 26 percent said they were agnostics and 14 percent said they were atheists. Though the survey was conducted through the Internet, the participants came from diverse socioeconomic situations: 17 percent reported a family income of $25,000 or less a year; 31 percent an income between $25,001 and $50,000; 33 percent an income between $50,001 and $100,000; and 19 percent an income of more than $100,000.

Of course, we also asked the women about their relationship status and sexual orientation. Approximately 80 percent reported being in a relationship at the time, whereas 10 percent were currently dating but were not in a long-term relationship. Ninety-three percent of the women said they were predominantly or exclusively heterosexual, with 2 percent identifying as bisexual and 5 percent identifying as predominantly or exclusively homosexual. Eleven percent actually did not choose one of these labels, opting for “other”—including gay, lesbian, asexual, bi-curious, hetero-flexible, omnisexual, pansexual, queer, straight-plus, fluid, open, polyamorous, still questioning, and various combinations such as “mostly heterosexual plus a touch of gay.”

One of the surprises in our study was that for each reason that impels a woman to have sex, we discovered both successes and failures. Sex was often incredibly pleasurable, giving women a sense of excitement, love, connection, and self-exploration:

I have found . . . two things are important—being able to be really intense sexually with the person, while simultaneously being able to laugh heartily and really enjoy the experience of being with the person in a different way. It’s almost like the laughter and the sex satisfy two basic human urges simultaneously.

—heterosexual woman, age 42

Women enjoy their sexiness and their sexuality.

But goals sought through sex are sometimes not reached. Indeed, sex sometimes leaves women feeling lonely, bitter, and regretful. One woman in our study sought sex in order to relieve her loneliness and feelings of being unattractive, but it didn’t work out that way:

I had sex in my last relationship so I would not feel so damned lonely and unlovable. It was a stupid thing because it ended up worsening the feelings for me. . . . I regret it now because we didn’t really know each other very well and were not really sure where we were going. We split up after another month.

—heterosexual woman, age 39

For every failure, however, we discovered sexual encounters of great success and true poignancy. Here is how one woman described sex as a way of boosting her self-confidence:

I had sex with a couple of guys because I felt sorry for them. These guys were virgins and I felt bad that they had never had sex before so I had sex with them. I felt like I was doing them a big favor that no one else had ever done. I felt power over them, like they were weaklings under me and I was in control. It boosted my confidence to be the teacher in the situation and made me feel more desirable.

—heterosexual woman, age 25

Another believed sex was a means of experiencing God:

I can’t really describe this experience . . . but pure joy and connection with another person I feel is becoming closer to the cycles of life and the underlying palpable energy of the world . . . in essence, God.

—heterosexual woman, age 21

Through the voices of real women, wide-ranging scientific and clinical findings, and our own original research, women’s sexuality can be seen in all of its textures, whether a sexual encounter leads to pleasure, remorse, emotional connection, or transcendent love.

We believe the end result will aid more informed sexual decision making—when, how, and, of course,
why
to have sex, in a relationship or outside one. Although this is not designed as a “self-help” book, we believe that readers will glean information that they can use in their own lives and share with their sexual partners. We hope that this book provides readers with a new set of lenses for viewing the many nuanced facets of women’s sexual psychology.

Why Women Have Sex