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Relationships

What’s in a Kiss?

In sexual politics, the kiss is both ambassador and spy.

“Kiss me and you will see how important I am."

—Sylvia Plath

The erotic kiss (as opposed to the kiss of respect, friendship, courtesy, or parent-child) is recognized in most cultures around the world. The vast majority of adults all over the globe have experienced the awkwardness, excitement, confusion, and pleasure of it. But one must admit that on its face, the practice of kissing is more than a bit strange. Why would the exchange of saliva and dinner salad remnants be considered a desirable event, a ritual of passion? Given that the erotic kiss is so common, it must play an important role in the dance of human sexuality. But what exactly is that role?

Opinions among scholars differ as to the function and origins of kissing. One hypothesis is that the kiss has evolved as a mechanism for gathering information about potential sexual partners. A kiss brings us into close physical proximity with the other, close enough to smell and taste them. The face area is rich with glands secreting chemicals that carry genetic and immunological information. Our saliva carries hormonal messages. A person's breath, as well as the taste of their lips and the feel of their teeth, signals things about their health and hygiene, and thus their procreative suitability.

Another hypothesis claims that the kiss functions primarily on the level of psychology, as a way to express and reinforce feelings of trust, closeness, and intimacy with another. Just like the clicking of wine glasses allows us to bring hearing into the sensory experience of drinking (which already involves all the other senses), so the kiss allows us to invite the senses of taste and smell to partake in the celebration of intimacy and make the event deeper and more complete.

In addition, when we kiss someone, we bring that person into our vulnerable personal space and agree to take the risk of catching an infection or disease. A kiss is therefore an implicit expression of openness and trust. A kiss also shows that you do not recoil from the other’s bodily fluids. Recent research has suggested that sexual arousal, especially among women, functions to suppress feelings of disgust. In this context, the kiss may serve as evidence and expression of sexual arousal. This theory predicts that kissing will not be an integral part of sexual activities where genuine desire and intimacy are absent. Indeed, the kiss is not common among sex workers and their clients, or rapists and their victims.

An additional line of thinking has focused on the kiss as a means of seduction and sexual stimulation. Women's lips, it is difficult to deny, resemble the labia. The practice of women around the world of coloring their lips red—a color linked to sexual arousal—suggests the role the lips play in seduction. Research has suggested that men prefer wetter kisses, with more involvement of the tongue than do women. The tongue, it is difficult to deny, is a phallic organ. The combination of a moist open mouth and a penetrating tongue simulate intercourse quite distinctly, and give easy rise to sexual imagining and, perhaps, sexual excitement.

In addition, some researchers speculate that the male preference for wet kisses is related to the fact that male saliva contains testosterone, a hormone linked to sexual arousal in both genders. A wet kiss may deposit testosterone into the woman's mouth, thereby acting to increase her sexual arousal.

The evolutionary anthropologist Helen Fisher of Rutgers University in New Jersey has proposed an integrated theory of the role of kissing. According to Fisher, the kiss plays a role in each of the three phases of our evolved reproductive strategy: first, the kiss helps inspire and direct the libido, which causes us to desire sex with multiple partners. Later, the kiss works to stoke the fires of romantic love, the deep infatuation that motivates us to choose one of many partners. Finally, the kiss helps us sustain and reinforce the ongoing attachment bonds, which allow us to endure together long enough to raise our children (our gene carriers) into sexual maturity.

An interesting set of findings emerging from the research relates to gender differences in attitudes and expectations about kissing. Several years ago, Robert Gallup from the University of Albany in New York and his colleagues collected detailed data on this issue from over a thousand young Americans. Women ranked the kiss as more important in both short and long term relations. Men rated kissing as decreasing in importance over the duration of a relationship. Half of the men (compared to only 14 percent of women) said they would have sex with someone without kissing them first. Both men and women reported that a good kiss was not in itself sufficient reason to develop a romantic relationship. But women in the study reported that the smell and taste of their kissing partner weighed heavily in their decision to continue kissing and pursue a relationship. For them, an unsuccessful first kiss could eliminate a potential partner from contention.

Gallup’s study also showed that the concept of the kiss as a distinctly sexual act is more common among men. Men routinely expect that kissing will lead to intercourse, feel more entitled to expect intercourse after kissing, and tend to characterize "a good kiss” as one leading to sex. Consequently, women sometimes find themselves under male pressure to kiss, and many reported being kissed against their will as men attempted to pressure them toward intercourse.

Researchers Rafael Wlodarski and Robin Dunbar of Oxford University published an interesting study this year of more than 900 participants (mentioned recently in a New York Times article). They, like Gallup and colleagues, found that women considered kissing as more important than did men, and considered it more an aid to, and expression of, relationship intimacy. The British researchers found that women value the kiss at the beginning of the relationship more if they are ovulating, suggesting that kisses are used to collect information on the fitness of potential mates.

Another interesting nuance: men and women who rated themselves as more attractive and who had more sexual experiences rated the kiss as more important. The fact that people who are more attractive and have more sexual options rely more on the kiss suggests kissing’s role as a tool for sexual mate selection and seduction. Participants also reported that when it comes to short term casual relations, kissing is more important before intercourse than during or after. When it comes to serious and stable long term relationship, kissing before, during, and after sexual intercourse is equally important. These findings indicate again that the function of the kiss varies depending on the nature of the relationship.

The role of kissing in improving the quality of long-term relationships was examined several years ago by the family communications scholar Kory Floyd and his colleagues at Arizona State University. The researchers randomly assigned fifty-two participants (all involved in long term relationships) into one of two groups and instructed the members of the experimental group to kiss more frequently with their partners for a period of six weeks. Blood tests and questionnaire data collected before and after showed that members of the experimental group experienced decreased cholesterol, decreased stress, and improved quality of relationship. Similarly, researcher Wendy Hill of Lafayette College in Pennsylvania found a few years ago that kissing for fifteen minutes led to a significant decline in the level of stress hormone cortisol in participants.

In conclusion, kissing appears to have two main uses: in short-term relationship, the kiss is more sexual, and serves as a tool for selecting and seducing suitable sexual partners; in long-term relationships, the kiss is an expression of psychological closeness, and a means of preserving and enhancing feelings of intimacy in the relationship.

In addition, the research suggests a possible gender difference in how kissing is perceived and used. Men, in general, may regard the kiss and the information it provides less than do women. Men tend to use kissing as a potential gateway to intercourse. They are more willing to forego kissing for intercourse, and their interest in kissing their spouses decreases over time.

Women, in general, may regard the kiss as more important and attribute to it more meaning in the process of choosing a partner and maintaining a relationship. Women tend to see kissing less as a sexual act and more as an intimate act. Women rely more on the kiss to identify and assess a potential partner. They tend to be more attuned to the taste and smell of the man, and are much less willing to have sex without kissing beforehand. They are also somewhat more likely to use a bad kiss as reason to break off contact with a potential lover.

Despite the differences in attitudes towards it, kissing, it seems, benefits both genders. Generally, couples that kiss more frequently report improved and more satisfying relationships.

“Kisses are a better fate than wisdom,” wrote the poet e. e. Cummings. So perhaps you’d be wise to turn off your computer right about now and go find someone to kiss.

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