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Did humor evolve as a sign of mental fitness?

Potential friends and mates flock to funny people. Many a grim, solitary soul can vouch for that. But the possibility that humor evolved in humans as a sign of mental fitness—and a way to increase reproductive success—finds support from a University of Colorado researcher.

Daniel Howrigan, a doctoral candidate in psychology and a researcher in the CU Institute for Behavioral Genetics, has tested the theory that people who are intelligent (or, more generally, “mentally fit”) are typically funnier than less-intelligent people.

He found that people who scored higher on intelligence tests also tended to be seen as more amusing. Though the link between intelligence and humor might seem self-evident, Howrigan’s experiment is one of the first to connect those dots scientifically.

Pictures and stories intended to be humorous that were created by people who scored higher in “general intelligence” were rated as being funnier, Howrigan found. His findings stem from an experiment on 185 California college students, including 115 women and 70 men. It was published last year in Evolutionary Psychology, a scientific journal.

Howrigan is quick to note that his work does not demonstrate a universal correlation between intellect and hilarity: “By no means is this saying humor is intelligence.”

Indeed. Try amusing yourself with Wittgenstein’s “Tractatus Logico-Philosophicus.”

Howrigan became interested in the evolutionary basis of humor partly because of the work of Geoffrey Miller, a University of New Mexico assistant professor of psychology. Miller’s book “The Mating Mind: How Sexual Choice Shaped the Evolution of Human Nature” rebutted theories that humor evolved as a way to promote group bonding, to discharge nervous tension, or to keep people healthy.

“Such theories predict that we should laugh at any joke, however stupid, however many times we have heard it before, yet we do not,” Miller wrote. “A good sense of humor means a discriminating sense of humor, not a hyena-like shriek at every repetitive pratfall.”

Such discrimination, Miller argued, makes more sense if “humor evolved in the service of sexual choice, to assess the joke-telling ability of others.”

In this view, people “produce” humor to demonstrate genetic fitness, to flaunt their desirability.

Howrigan observes that humor is a relatively human-specific behavior. “The evolutionary question is why?”

“At the end of the day, a lot of this serves our reproductive ends,” Howrigan says. “If this is aiding in reproduction … it’s deemed as a fitness characteristic.”

The volunteers in Howrigan’s experiment took IQ and personality tests, the latter of which assessed five key traits: openness, conscientiousness, extraversion, agreeableness and neuroticism.

The volunteers also did three tasks designed to show their wit. They completed a personal profile (attempting comical snippets on such themes as “my outlook on life”). Then, they responded to a mock-e-mail from a friend, answering questions like, “How would you make a marriage exciting after the first couple of years.”

Finally, the research subjects were asked to draw four pages of funny pictures of animals and humans (including a giraffe and a politician).

The attempts at humor were then judged by 28 graduate-student and student volunteers. Judges rated each profile, e-mail response and drawings on a 1-7 scale, with 1 being “not funny at all” and 7 being “hilarious.”

General intelligence correlated with “humor production,” as did, to a lesser extent, openness and extraversion. These results buttress Miller’s theories, Howrigan notes. He also points out that another lab has since replicated his results.

At the same time, he notes, there are limitations inherent in this study and in research on humor generally.

First, this study focused on written or drawn material rated by anonymous judges who did not know the identity or the gender of the would-be humorists. Therefore, “social setting, interpersonal relations, shared knowledge and spontaneity had to be sacrificed.”

Given the wall of anonymity between those striving to be funny and those trying to find some humor in it all, Howrigan’s experiment may give only a “partial glimpse” into the phenomenon of humor and how it relates to other patterns of individual differences.

Then there is the fact that “humor” is a broad term that encompasses everything from the Three Stooges’ silly slapstick to Sacha Baron Cohen’s scathing satire.

Though subjective, a good sense of humor seems as universally coveted as quiet walks on the beach. “It’s something that people not only enjoy but look for in other people,” Howrigan says.

The question is whether humor evolved as a way to display “mental fitness” and thus attract mates, or whether humor was an evolutionary byproduct of humans’ increasingly complex communication. That’s hard to know, partly because humor is not confined to mating rituals.

Meanwhile, Howrigan has turned his attention to other evolutionary questions. At CU, he is working on molecular genetics with Matthew McQueen and Matthew Keller, assistant professors of psychology and fellows in CU’s Institute for Behavioral Genetics. As Howrigan notes, it is difficult to support evolutionary models with behavioral research; researching on genes could be much more definitive.

But Howrigan remains intrigued by humor. “It does play an integral part of almost everybody’s life,” he observes. “It’s an amazing thing that we have the ability to laugh at all sorts of different things for all sorts of different reasons.” Even at our wit’s end.