Is humor inherited? Twin study suggests the ability to be funny may not run in the family

Some people seem naturally funny, always ready with a clever joke or a witty comment. Others struggle to land a punchline. But is a sharp sense of humor something we’re born with, or does it come from our surroundings and experiences? In a new twin study published in Twin Research and Human Genetics, researchers found that while people’s beliefs about their own sense of humor may reflect inherited traits, their actual ability to produce jokes that make others laugh appears to come almost entirely from environmental factors.

The study was led by Gil Greengross of Aberystwyth University and marks the first scientific attempt to measure the heritability of what researchers call “humor production ability.” While previous research has found that other cognitive abilities, such as intelligence and creativity, have moderate to strong genetic components, humor production ability had never been specifically examined in this way. The researchers wanted to fill this gap and better understand what contributes to individual differences in how funny people are.

“There is an ongoing debate about sources of individual differences for many psychological traits. How much of it is due to genes and how much is due to the environment. It’s well established the cognitive traits such as intelligence and creativity has a genetic basis but we were the first to test whether humor ability is also rooted in our genes,” explained Greengross, a lecturer in psychology.

To investigate how humor ability develops, the researchers turned to a long-standing method in behavioral genetics: twin studies. By comparing identical twins, who share nearly all their genes, with fraternal twins, who share only about half, researchers can estimate how much of a trait is influenced by genetics versus the environment.

The research team recruited over 1,300 adult twins from the TwinsUK registry in Britain, including 448 identical twin pairs and 196 fraternal pairs. The participants ranged in age from 21 to 89, with a median age of 66. Most were women, reflecting the demographics of the registry.

The researchers measured humor in several ways. Participants were asked to rate how funny they thought they were, as well as how often they made other people laugh. They were also asked to rate their twin’s sense of humor using the same questions. This provided a measure of subjective humor—how funny someone sees themselves or their sibling to be.

But to get a more objective measure of humor ability, the researchers used a widely accepted test from psychological studies: cartoon captioning. Each participant was shown two captionless cartoons and asked to write a funny caption for each. The cartoons, drawn from The New Yorker’s famous caption contests, featured quirky scenarios, like a wet bear taking restaurant orders or a couple viewing a house in outer space.

To rate how funny the captions were, the researchers enlisted 40 judges from the local community. Each judge rated a subset of the captions on a five-point scale from “not funny” to “very funny.” Captions were grouped into blocks and rated by different judges to avoid fatigue and bias. Three anchor judges rated samples from each block to ensure consistency across all ratings. The researchers then used a statistical method called the Many-Facet Rasch Model to generate a humor ability score for each participant, adjusting for variation in cartoon difficulty and rater leniency or severity.

What did the researchers find? People’s beliefs about their own sense of humor were moderately influenced by genetics. Identical twins tended to rate themselves and each other more similarly than fraternal twins did, suggesting some inherited component. In contrast, the judges’ ratings of the cartoon captions—the actual humor performance—showed no meaningful genetic influence. Both identical and fraternal twins performed similarly when it came to crafting funny captions, suggesting that the environment, not shared genes, played the biggest role.

This finding stands in contrast to much of the existing research on the heritability of cognitive traits. Studies consistently find that abilities like intelligence and creativity have significant genetic components, with heritability estimates often ranging between 40% and 80%. Humor ability, which overlaps with these traits in some ways, was expected to follow the same pattern.

“We found no heritability component for humor production ability, which counter all existing literature showing that cognitive abilities such as intelligence and creativity have substantial heritability,” Greengross told PsyPost.

Why might that be? One possibility is that creating humor is more socially and contextually shaped than other cognitive skills. Humor depends on timing, cultural knowledge, language, and social dynamics—all factors that can vary widely between individuals and environments. Unlike intelligence tests or math problems, humor tasks rely on subjective interpretation and audience feedback. This makes them harder to standardize and more sensitive to a person’s upbringing, peer group, education, or life experiences.

Another possibility is that the task itself—a cartoon caption contest—doesn’t fully capture what it means to be funny. Everyday humor is often spontaneous, conversational, and situational. Writing a caption in isolation is a cognitively demanding and somewhat artificial task, especially for older adults. Since most of the participants were over 60, some may not have been as comfortable with the exercise or as practiced at performing humor on demand. The judges, on the other hand, were younger, and their comedic preferences might not have aligned with the older participants’ styles.

The study also found a gap between people’s perception of their humor and their actual humor ability. Self-rated humor was only weakly correlated with caption performance. People who thought they were funny didn’t always write the funniest captions, and vice versa. This mismatch is consistent with past research showing that many people overestimate their sense of humor—especially men. In one previous study, over 90% of participants believed they had an average or above-average sense of humor.

The researchers also looked at how humor ability related to other traits, including general cognitive ability, as measured by a short test called the Cognitive Reflection Test. This test includes brainteasers that require people to override an intuitive, wrong answer in favor of a more thoughtful one. While the test scores showed high heritability, they were only weakly correlated with humor ability, again defying expectations.

“Science is complicated and unexpected,” Greengross said. “Our study reveals surprising results that are not in line with previous research. It might be a fluke, sometimes studies fail to find what they expect even though the effect is there, or perhaps we discovered something new, which is very exciting. We need to be careful as this is the first study on the topic and we will know more one a replication is conducted.”

Like any study, this one had limitations. Most of the participants were older women, so the findings might not generalize to younger populations or to men. The method of testing humor through captioning is widely used but doesn’t reflect real-world humor in conversation or performance.

“It’s not easy to assess humor ability,” Greengross noted. “We used a somewhat artificial task that ask participants to generate funny captions to captionless cartoons, later to be rated by independent judges. This is not the same as spontaneous everyday humor.”

And although the sample was large for a twin study, it may not have been big enough to detect small genetic effects. According to the researchers’ power calculations, a much larger sample—about six times the current size—would be needed to rule out the possibility of a small inherited component.

Still, the findings raise interesting questions about the origins of humor. If the ability to make people laugh doesn’t come from our genes, what parts of our environment shape it? Is it the media we consume, the people we grow up with, our level of education, or our personality traits? And why do some families seem to produce multiple funny people—like the Marx Brothers—while others don’t?

“We are working on a replication study to test how robust our results are on a different sample of twins,” Greengross said.

The study, “Heritability of Humor Production Ability – A Twin Study,” was authored by Gil Greengross, Nancy Segal, Stephanie Zellers, Paul Silvia, Claire Steves, and Jaakko Kaprio.