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Key points
- Laughter can be traced back roughly 16 million years to the common ancestor of both great apes and humans.
- Tickling, an unsophisticated form of humor observed in modern great apes, likely dates to the same period.
- More than simply a component of rough and tumble play, tickling can also served to distract and mollify.
In recent posts, I’ve argued that laughter, an expression I would suggest affirms a sense of mutual vulnerability, almost certainly originated in the common ancestor of the Great Apes some 14 to 18 million years ago. If the modern apes—chimpanzees, gorillas, and orangutans—echo the way in which laughter was first employed, primarily during play chases and play wrestling, there has obviously been a huge increase in both the scope and frequency of its use within our human lineage. But just how much has laughter’s role as a communicative behavior actually changed? Do Great Apes laugh in contexts other than physical play? Do they engage in humor? Do they purposefully solicit laughter, and if so, to what end?
This post represents the first of several in which I’ll speculate on the most likely course of evolution for laughter and humor since our split from the other Great Apes roughly 6 million years ago.
Tickling as humor
It’s been well-established that modern Great Apes purposefully tickle other members of their social group. Tickling, while seemingly a rather innocuous component of physical play, does, in fact, constitute a rudimentary form of humor. It’s a means of intentionally creating a sense of physical vulnerability in another, thereby soliciting self-lifting laughter. It’s no different than telling a riddle to impart a sense of cognitive vulnerability or relaying a bit of embarrassing gossip to highlight someone’s social vulnerability. Tickling another implies a sense of dominance over them and, simultaneously, one’s reluctance to take full advantage of it. These halfhearted attacks actually serve (in the long run, at least) to promote greater trust between the participants.
Outside traditional play bouts, however, there are, as most human parents and caregivers will attest, other motivations for tickling. It can, for example, be used as a way of distracting others. Is such a strategy employed by other Great Apes? It would seem so, as this exact behavior has been observed in wild chimpanzees. Jane Goodall (van Lawick-Goodall, 1971) describes two instances of mothers (Olly and Flo) distracting their young daughters (Gilka and Fifi).
...Gilka stopped and began to utter a series of low whimpers. For a brief time Olly ignored the child, then she reached out, drew Gilka close, and began tickling her. Soon Gilka was uttering the panting chuckles of chimpanzee laughter. The game had lasted for less than a minute when Olly pushed her daughter away and resumed her endless termite-fishing. Nevertheless, just as Fifi had been temporarily distracted from her attempts to touch or pull away Flint [Flo’s infant son] by a similar playful behavior on Flo’s part, so it was with Gilka. She looked around, picked up one of Olly’s discarded tools, and idly pushed it into an opened-up termite passage.
Goodall recorded another, even more striking example of tickling to distract, this time between two adult males after a successful hunt. The desired result was achieved without Mike resorting to aggression.
Another time, when David was watching Mike eating [monkey] brain and was begging very persistently, Mike started to tickle him, as a mother would do to her child to distract it from some desired objective. After a few moments the two adult males were both uttering loud chuckles of chimp laughter as they tickled each other. And it worked; when David could endure the tickling no more he moved away and Mike continued to eat brain undisturbed.
A second use of humor is to mollify. In an earlier post, I relayed a story about the tickle session Mike initiated following his truly aggressive attack on Flo after she took some food out of turn. Goodall interprets Mike’s gentle tickling as a means of reconciliation and then offers other insights on the subject.
How was it possible for her to enjoy such a relaxed interaction [referring to the tickling bout] with Mike so soon? The secret perhaps lies in the fact that although a male chimpanzee is quick to threaten or attack a subordinate, he is usually equally quick to calm his victim with a touch, a pat on the back, and an embrace of reassurance.
Chimps and bonobos express feelings of reassurance or empathy in many ways. Mutual grooming serves as the primary means of forming and maintaining social bonds in chimps and gorillas. Embracing, kissing, and genital rubbing seem to do the trick for bonobos. So, we must wonder if they at least have the capacity for humor beyond that of tickling.
To gain insight into this realm, we’re forced to look at those who are observed much more closely and given greater opportunity to express themselves. We need to consider apes in captivity, especially those that participate in language studies. This will be the subject of my next article.
This post was drawn from Chapter Eight of Why We Laugh: A New Understanding.
© John Charles Simon.
References
Simon, J. C. (2008). Why We Laugh: A New Understanding. Starbrook Publishing.
van Lawick-Goodall, J. (1971). In the Shadow of Man. Boston: Houghton Mifflin Company.
