Robert Provine wants me to see his Tickle Me Elmo doll. Wants me to hold it, as a matter of fact. A professor of psychology and neuroscience at the University of Maryland, he has been engaged for more than a decade in a wide-ranging intellectual pursuit that has taken him from the play of young chimpanzees to the history of American sitcoms—all in search of a scientific understanding of that most unscientific of human customs: laughter.
The Elmo doll happens to incorporate two of his primary obsessions: tickling and contagious laughter. “You ever fiddled with one of these?” Provine asks, as he pulls the doll out of a small canvas tote bag. He holds it up, and after a second or two, the doll begins to shriek with laughter. There’s something undeniably comic in the scene: a burly, bearded man in his midfifties cradling a red Muppet. Provine hands Elmo to me. “It brings up two interesting things,” he explains. “You have a toy that’s a glorified laugh box. And when it shakes, you’re getting feedback as if you’re tickling it.” (Elmo has been so popular that in September 2006 Fisher-Price released a tenth anniversary version of the doll, called Elmo T.M.X. It not only laughs and vibrates but rolls on the ground pounding its fists, pleading for the supposed tickler to stop.)
Think about that Tickle Me Elmo doll. We take it for granted that tickling causes laughter and that one person’s laughter will easily “infect” other people within earshot. Even a child knows these things. (Tickling and contagious laughter are two of the distinguishing characteristics of childhood.) But when you think about them from a distance, they are strange conventions. We can understand readily enough why natural selection would have implanted the fight-or-flight response in us or endowed us with a sex drive. But the tendency to laugh when others laugh in our presence or to laugh when someone strokes our belly with a feather—what’s the evolutionary advantage of that?
