Humans (some) have the ability to take things with humor; That is, they have a certain facility for making jokes and laughing at themselves and their peers in an openly positive way. But, in this aspect, humans are not unique either. Various studies and simple observation have shown that other species have a sense of humor or, at least, that's how they appear.
A team of experts in cognitive biology and primatology from the University of California, Los Angeles (United States), the Max Planck Institute for Animal Behavior (Germany), Indiana University (USA), and the University of California, San Diego (USA) has now carried out a unique study in which they show that even young individuals of four species of primates close to ours have a sense of humor to the point of making jokes and making fun of their companions in a friendly way.
Among the conclusions of this research, the authors propose that humor would have appeared in the evolution of the direct ancestors of humans and all primates at least 13 million years ago, as indicated in the article presenting their results that is published this February 14 in the magazine
Teasing is an important part of human interaction that relies on social intelligence, the ability to anticipate future actions, and the ability to recognize and appreciate violating the expectations of others. Teasing has a lot in common with pranks, and playful teasing can be seen as a cognitive precursor to pranks, the authors of the new study recall as a preamble to the presentation of their findings.
Psychology and pedagogy studies have shown on several occasions that the first forms of playful teasing in humans emerge even before babies say their first words, already at eight months of age. The earliest forms of teasing are repetitive provocations that often involve surprise. Babies tease their parents by playfully offering and removing objects, testing social rules (so-called provocative noncompliance), and interrupting the activities of others.
The new observational study led by Isabelle Laumer, Sasha Winkler, Federico Rossano and Erica Cartmill presents evidence of playful teasing in four species of great apes: orangutans, chimpanzees, bonobos and gorillas.
"Great apes are excellent candidates for playful teasing, as they are closely related to us, engage in social games, laugh, and show a relatively sophisticated understanding of the expectations of others," says Isabelle Laumer, a postdoctoral researcher at the University from California and first author of the study.
The team analyzed spontaneous social interactions that appeared to be fun, slightly harassing, or provocative. During these interactions, the researchers observed the prankster's actions, body movements, facial expressions, and how the targets of the teasing responded in turn. They also assessed the intentionality of the provocateur by looking for evidence that the behavior was directed at a specific target, that it persisted or escalated, and that the provokers expected a response from the target.
The researchers found that orangutans, chimpanzees, bonobos and gorillas engaged in intentionally provocative behaviors, often accompanied by characteristics of play. They identified 18 different teasing behaviors. Many of these behaviors seemed to be used to provoke a response, or at least to attract the target's attention.
“It was common for provocateurs to repeatedly wave or swing a body part or object in the middle of the target's field of vision, hit or poke him, stare him in the face, interrupt his movements, pull his hair, or engage in other behaviors. "They were extremely difficult for the target to ignore," explains Erica Cartmill, professor at the universities of California and Illinois, co-author of the study.
Although playful teasing took many forms, the authors note that it differed from play in several ways. “Playful teasing in great apes is one-sided, largely coming from the teaser throughout the entire interaction, and rarely reciprocated,” explains Cartmill. "Animals also rarely use play signals such as the primate 'play face', which is similar to what we would call a smile, or 'hold' gestures that indicate their intention to play."
In the new study, it was observed that playful teasing occurred mainly when the apes were relaxed and shared behaviors similar to those of humans. "Like teasing in children, playful teasing in apes involves unilateral provocation, a response wait in which the provocateur looks toward the target's face directly after a teasing action, repetition, and elements of surprise." , explains co-author Isabelle Laumer.
The researchers reviewed studies by experts such as Jane Goodall and other field primatologists in which apparently humorous behaviors have been mentioned, for example, in chimpanzees, but "this new study was the first to systematically study playful teasing," they note. favor. “From an evolutionary perspective, the presence of playful teasing in the four great apes and its similarities to playful teasing and teasing in human infants suggests that playful teasing and its cognitive prerequisites may have been present in our last common ancestor, at least.” 13 million years ago,” explains Isabelle Laumer in a note released by the Max Planck Institute for Animal Behavior.
“We hope our study inspires other researchers to study playful teasing in more species to better understand the evolution of this multifaceted behavior. “We also hope this study raises awareness about the similarities we share with our closest relatives and the importance of protecting these endangered animals.”
