Why do humans laugh, even when something isn’t funny?
Laughter might not be the best medicine, but it’s certainly a fundamental part of the human experience.
It’s a mostly involuntary act; in fact, studies have shown that people can always distinguish between fake laughter and the real thing. It’s contagious, which may indicate that it’s an even older form of communication than the spoken word.
But why do we laugh? What purpose does it serve, if any?
To find out, Robert Provine, a neuroscientist and psychology professor, used tape recorders to document more than a thousand “laugh episodes” in real-world situations. The results, published in Provine’s book Laughter: A Scientific Investigation, were shocking.
Provine found that less than 20 percent of his “laugh episodes” were in response to something actually funny. Most people laughed after innocuous, everyday statements: “I’ll see you later,” “Have a good day,” and other small talk.
One theory holds that humans use this form of laughter as punctuation.
“Mutual playfulness, in-group feeling, and positive emotional tone—not comedy—mark the social settings of most naturally occurring laughter,” Provine wrote. “Research that focuses only on the response of an audience to jokes (a common laboratory scenario) targets only a small subset of laughter.”
Laughter is a cue to other people, not a simple form of self-expression. Humans don’t laugh much when they’re alone—they’re more likely to talk to themselves than to laugh to themselves.
In 2005, an evolutionary biologist, David Sloan Wilson, and an undergraduate, Matthew Gervais, put forth a theory that laughter evolved at two separate points. About 2–4 million years ago, humans began laughing in response to humor.
This type of laughter, Wilson and Gervais said, was likely related to the panting seen in primates during play fighting. Primates loudly pant to show other members of their group that they’re not injured; eventually, this became a louder vocalization.
“What the humor is indexing and the laughter is signaling is, ‘this is an opportunity for learning,'” Gervais said, according to Slate. “It signals this is a non-serious novelty, and recruits others to play and explore cognitively, emotionally and socially with the implications of this novelty.”
Eventually, humans evolved to laugh at things that weren’t necessarily funny.
We use this mimicked laughter in an attempt to manipulate others.
“[Mimicked] laughter came to occur in aggressive, nervous, or hierarchical contexts, functioning to signal, to appease, to manipulate, to deride, or to subvert,” Gervais and Wilson wrote in their 2005 paper.
The researchers characterized this as the “dark side” of laughter, noting that it’s inherently manipulative. However, all forms of communication could be characterized in the same way; laughter’s simply a tool that we use to change the context of social situations.
The record’s success was solely due to the contagious nature of the laughter itself. People, it seems, want to laugh—regardless of the circumstances.