The question of whether gorillas possess a sense of humor addresses the inner mental lives of non-human animals. Scientists find that complex emotional states and high-level cognition, like appreciating a joke, are difficult to prove without language. While gorillas exhibit playful behavior, determining if they experience the human-like cognitive state of finding something funny remains a challenge. Research suggests that while gorillas may not tell complex narrative jokes, they engage in behaviors that represent the evolutionary origins of humor.
Distinguishing Play Behavior from True Humor
The scientific definition of humor requires a threshold exceeding simple rough-and-tumble play. Basic play, seen across many mammalian species, is characterized by reciprocity, specific signals like the “play face,” and its function in developing motor skills and social bonds. True humor, by contrast, is rooted in the cognitive ability to recognize and appreciate an incongruity, often involving an intentional violation of a social or physical expectation. It requires a sophisticated understanding of what another individual expects.
This distinction separates a playful wrestling match from an intentional prank. The playful teasing observed in great apes is considered a cognitive precursor to human joking. This behavior is typically one-sided and provocative, involving a teaser disrupting another’s activity or attention and then waiting for a reaction. Such interactions require the teaser to anticipate the recipient’s mental state, moving beyond simple social play.
Observable Evidence of Intentional Play in Gorillas
Gorillas, particularly juveniles, exhibit a wide repertoire of highly social and intentional play behaviors. These interactions often involve mock aggression, such as wrestling, chasing, and spinning, which practice motor skills and establish social dynamics. During these bouts, gorillas produce a distinct vocalization known as the “gorilla giggle.” This loud, long panting sound is functionally similar to human laughter and is often heard during tickling or intense physical play.
Gorillas also possess a clear “play face,” a relaxed, open-mouth display with no teeth showing, which signals non-aggression and invites play. More complex, intentional actions are categorized as playful teasing, a behavior observed across all four great ape species. These actions include repeatedly waving a stick in front of a peer’s face or disrupting a resting gorilla by poking or pulling hair. Such behaviors are designed to provoke a reaction and demonstrate an understanding of social boundaries.
The intent is confirmed by the teaser waiting for a response, suggesting the gorilla monitors the effect of its actions. Researchers have identified eighteen distinct playful teasing behaviors. Many of these involve using objects or disrupting movement to elicit attention or a reaction. This intentional provocation, while not a joke in the human sense, indicates a capacity for social manipulation and is a precursor to appreciating incongruity.
The Advanced Cognition Required for Humor
The most complex forms of humor, such as sarcasm, irony, or narrative jokes, depend on Theory of Mind (ToM). ToM is the ability to attribute mental states—beliefs, intents, desires, and knowledge—to oneself and others. For a gorilla to genuinely appreciate a joke, it would need to understand that the “punchline” relies on a false belief or an unexpected outcome in the recipient’s mind.
Recent studies suggest that great apes, including gorillas, possess some sophisticated components of ToM. Research shows that apes can anticipate how an individual will behave based on what that individual has seen or believes, even if the ape knows that belief is incorrect. This ability to track another’s false belief is a significant cognitive step, demonstrating an understanding that different minds hold different information.
While this capacity for understanding expectations and beliefs is present, gorilla cognition is best described as having the prerequisites for humor, rather than humor itself. The observed behaviors are classified as complex social play or playful teasing, representing the evolutionary roots of the human sense of humor. The presence of these behaviors in gorillas, which diverged from the human lineage millions of years ago, suggests that the foundation for finding amusement in social incongruity has a deep evolutionary history.