Chapter 1: The Birth of Laughter

There comes a pivotal moment in the lives of human infants when they first laugh. Beyond simply experiencing basic sensations such as hunger, discomfort, heat, and cold, babies begin to recognize unusual or amusing occurrences, leading to their first giggle. This initial response indicates a sophisticated cognitive process at work, suggesting that the roots of humor are deeply embedded within our genetic makeup. The divergence of our hominoid lineage from other great ape species took place around 13 million years ago, yet we still observe the capacity for humor across these varied lineages, implying that the cognitive foundations for humor must have existed long ago.

Humor, particularly through joking and playful teasing, serves as a vital instrument for social development. It is often more foundational than verbal communication, as infants and toddlers frequently engage in humor before mastering language. Through joking and teasing, young children learn and reinforce social norms, demonstrating that adults also partake in this behavior, albeit with varying degrees of skill.

Theory of mind, which refers to the ability to comprehend the thoughts, beliefs, and desires of others, plays a crucial role in how humor operates. A preverbal child who provokes a parent and anticipates their reaction exemplifies this concept in its early, playful form. This is similarly observed in games like peek-a-boo. As the late psychologist Daniel Stern noted, “Teasing others requires an understanding of their thoughts and an ability to elicit reactions, whether through amusement or discomfort.”

While humor may appear basic, it is a complex cognitive skill observed across many species, making its presence in other animals particularly fascinating. Recent research has taken a systematic approach to document playful teasing behavior in various great ape species.

Photo source: BOS Foundation BPI

Chapter 2: The Playful Teasing of Great Apes

“Great apes are prime candidates for playful teasing due to their close evolutionary relationship with humans, their engagement in social play, and their ability to express laughter,” states Isabelle Laumer, PhD, a primatologist at the Max Planck Institute of Animal Behaviour. Laumer dedicated 75 hours to observing interactions among gorillas, bonobos, chimpanzees, and orangutans. She created a coding system to classify instances of playful teasing, which proved to be a frequent interaction that was intentional and varied in both aggressiveness and playfulness.

The teasing individual often awaited a reaction from their companion, engaging in behaviors such as running away, pausing, and looking back, all of which elicited a response. Depending on the reaction's intensity, the teaser would adjust their approach, indicating a nuanced understanding of social dynamics.

There are notable differences between playful interactions across species. For instance, while playfulness tends to be reciprocal among young animals like puppies and kittens, playful teasing among great apes is often asymmetrical, where one participant is aware of the joke while the other is the target of annoyance. This mirrors human social interactions in many ways.

Despite these similarities, a significant difference was noted in the study regarding play behavior. Typically, human infants play with peers of similar size and social standing, aligning with the motor training hypothesis. However, in great apes, some juveniles were observed to tease larger, higher-ranking adults, suggesting a unique social dynamic. In bonobos, juvenile males often teased lower-ranking females, likely as a strategy to enhance their own social standing, a behavior referred to as the “rank improvement hypothesis,” though this was not consistently observed across all species studied.

Laumer's research posits that playful teasing in great apes is likely a homologous trait inherited from our last common ancestor, which possessed cognitive elements conducive to humor.

Shared moments of joy and amusement among great apes, including humans, serve to strengthen social connections. It is a profound realization that humor predates language, with teasing and basic forms of humor acting as precursors to the intricate social interactions we observe in humans today. The expressions of joy — grins, smirks, chuckles, and smiles — have been present for millions of years, with humans being the current bearers of these age-old behaviors.

The first video, "Ancient Greek Comedy: My Favorite Joke," explores humor's historical context and its evolution through time.

The second video, "Queen's ASO: Ancient Humour," delves into the comedic traditions of ancient civilizations and their relevance to modern humor.