The Mystery of Why We Kiss

A recent visitor to my website, GreatSexAfter40.com, complained that her husband’s aversion to kissing was stressing their marriage. This is not the first time I’ve heard people complain about their lover’s poor kissing or unwillingness to kiss. But kissing is a frequently overlooked element of sexuality. Also known as smooching, necking, snogging, making out, lip locking, bussing (archaic), and osculation, kissing is rarely mentioned in sexology resources, which is odd because for many lovers, kissing is one of the most important, most erotic elements of sex.

One reason why the sex literature largely ignores kissing is that it often occurs in nonsexual contexts with non-erotic meanings, among them: kissing another’s cheek (or air kissing) to signal greeting or farewell, kissing children’s minor injuries to heal them, kissing the Pope’s ring or a king’s hand or garments to signal reverence and fealty, kissing dice for good luck, and kissing that signals betrayal, condemnation, or contempt as in Judas’ kiss, the Mafia’s kiss of death.

The poet Percy Bysshe Shelley defined kissing as “soul meeting soul on lovers’ lips.” It’s certainly possible for lips-only kissing to express deep love, but for soul to meet soul, most lovers engage in open-mouth kissing with tongue contact, known in the English-speaking world as French kissing.

Most — but not al l— people consider kissing with tongue contact to be extremely intimate. Some consider it as intimate as intercourse. Kissing’s intimacy is also reflected in a term used to describe fellatio and cunnilingus —“genital kissing.” Meanwhile, many sex workers who routinely provide fellatio and vaginal and anal intercourse, refuse to kiss customers because, they say, it’s “too intimate.”

Ancient Sanskrit texts (c. 1000 B.C.) provide the earliest documented evidence of human kissing. Ancient Europeans kissed, but the paucity of references in ancient Greek literature suggests that the practice was less frequent 2,000 years ago than it is among Europeans today.

Most cultures around the world kiss, but not all. Europeans introduced the practice to the indigenous peoples of Australia, Tahiti and several locales in Africa. In some Asian cultures, lovers kiss only in private. Doing so in public is considered indecent.

Kissing is a mystery. Only two other species are known to kiss as humans do, chimpanzees and bonobos. They kiss to communicate attachment and to reduce group social tensions. But only humans and bonobos kiss deeply during sex.

Nor is it clear why kissing evolved. Some scientists speculate that it originated with mammalian infant suckling. Human lips contain a wealth of touch-sensitive nerves, and lip stimulation activates a surprisingly large area of the brain. But all mammals suckle their young while only a tiny minority of mammals kiss.

Other researchers suggest that kissing originated in mammalian pre-chewing of food before feeding it to young mouth to mouth. Again, many more mammalian species pre-chew food than kiss. Some scientists theorize that kissing evolved to bring noses close enough to sense others’ pheromones, chemicals that play a subtle but well-documented role in attraction and attachment. Again, many species respond to pheromones, but only a few kiss.

Read more: Michael Castleman MA, PsychologyToday

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