Laughter and humor are highly valued in the sexual marketplace. In a study of 3,745 personal ads published by heterosexual men and women in eight U.S. national newspapers on Sunday, April 28, 1996, men offered “sense of humor” or its equivalent (“humorous”), and women requested it (Provine Reference Provine2000). Women, however, couldn't care less whether their ideal male partner laughs or not – they want a man who makes them laugh. Women sought laughter over twice as often as they offered it. The behavioral economics of such bids and offers is consistent with the finding that men are attracted to women who laugh in their presence (Grammer & Eibl-Eibesfeldt Reference Grammer, Eibl-Eibesfeldt and Koch1990). Without such a balance between the value of bids and offers, there would be no market for laughter and humor, and the currency of these behaviors would decline. It is significant that this orderly laughter scenario occurs at a low level of conscious awareness – laughter is not a matter of deciding to speak “ha-ha.” Most people have difficulty laughing convincingly on command; it happens spontaneously in the appropriate social context. Laughter, like crying, is an honest signal that is hard to fake.
Although laughter is under low voluntary control, its stimuli are not, and show strong sexual dimorphism. Men are the most effective laugh getters (Provine Reference Provine1993; Reference Provine2000). Both men and women laugh more at male than female speakers, a likely reason why there are more male than female comedians. This trend starts early in life; most class clowns are boys. The essential stimulus of laughter is another person, male or female, not humor. Laughter is 30 times more frequent in social than solitary situations, and, when laughter occurs, only 10 to 15 percent follows comments that are jokes or other formal attempts at humor. Contagious laughter – laughing in response to perceived laughter – may be the ultimate example of the reciprocity of emotional expression. Contagious yawning may be another.
Tickle, the primordial laugh stimulus, joins humor as another laugh stimulus under voluntary control. The sexual component of tickle is suggested by its strongly heterosexual character (Provine Reference Provine2000; Reference Provine2004). Aside from physical play with children, adult males tend to tickle females, and vice versa. The ticklee of choice is not random. We tickle and are tickled by friends, family, and lovers. When was the last time you were tickled by a stranger? The reasons given most often for tickling are to “show affection” and to “get attention,” not to antagonize. Even confirmed tickle haters may reconsider their position when they realize that the give-and-take of tickle battles is central to sexual foreplay and intercourse.
If you still doubt the sociality of tickle, consider that you can't tickle yourself (Provine Reference Provine2000; Reference Provine2004). It takes two to tickle. In contrast, you can tap your own patellar tendon and evoke a perfectly normal knee jerk. The sociality and reciprocity of tickle are neurologically programmed. Ticklees struggle, fend-off the tickling hand, laugh, and retaliate. Retaliation is the basis of the give-and-take of tickle battles, and what binds us together during the rough-and-tumble play of childhood and the sex play of adulthood. Bad tickle experiences are associated with the absence of reciprocity, such as when a person is held down and tickled. Nonconsensual tickle, like nonconsensual sex, is unwelcome and unpleasant. Vigil's emphasis on the reciprocity of emotional relationships is well placed.
Vocal crying and tearing are emotional signals that provide informative contrasts with laughing, humor, and tickling. The first study of tearing as a visual signal of sadness found that faces with tears appeared sadder than identical faces with tears removed by digital image processing (Provine et al. Reference Provine, Krosnowski and Brocato2009). Tear removal produced faces that were not only less sad but of ambiguous emotional state. Thus, emotional tearing provides a significant visual cue of sadness, complementing the neuromuscular instrument of facial behavior that may not quite be up to the task. Emotional tearing, unique to humans, is a significant advance in Homo sapiens as a social species. The study detected no difference in the perceived sadness of teary and tear-free faces as judged by male and female subjects. However, as noted by Vigil, females cry much more than males, which provides females with more potential vocal and visual stimuli of the emotional state.
Tearing and vocal crying, solicitations of caregiving and expressions of neediness, may be exceptions to emotional reciprocity of the sort considered for laughing, humor, and tickling. Caregiving, although adaptive within the framework of reciprocal altruism, is unattractive and costly for the provider, a fact revealed in the psychosexual marketplace of personal ads. You are unlikely to find people advertising their neediness or seeking it in others.
