Following the last post (“Social boundary theory of humour – predictions for psychiatry“) in which I explored whether some predictions that the social theory of humour regarding humour suggest with regard to certain mental conditions (and drugs), TinyCO2 & my son have been making some very useful comments. This has led me to postulate a potential evolutionary pathway for humour.
The result of the previous article and the “loose” correlation with psychiatric conditions AND DRUGS LIKE ALCOHOL is that although I’m more and more confident there’s something in the social boundary theory. However, just saying humour is humorous because it’s “on the edge” of what is socially acceptable seems to be missing a lot. But taking many of the comments I think I can start to tie together some of the complexity by postulating an evolutionary theory of humour.
The presence of what appears to be “laughter squeaks” in rat when tickled (or mock fought) is interesting because any universal theory would need to fit something as simple as this situation with a rat which obviously doesn’t have our language ability.
It suggests that laughter may have started in some kind of mutual touching which could be sexual, but is much more likely to have been some kind of mechanism in mock fights. It’s meaning would be something like “I know you are pretending to kill me, but I’m OK with it”. But it might also have a sexual element as in “I know you are trying to touch me in a way that I could find unacceptable … but I don’t (yet) take it as a threat”. This requires no language.
The next step up, is when you empathise with others … so that you laugh not at a mock attack on yourself, but on other people. In other words, we laugh when someone is pretending to hit another (aka slapstick). This is a large part of what we’d normally call “play” something which is fairly common in many mammals. And play is often used as a way of practising fighting in animals. Again this requires no language and (I believe) is the type of humour appreciated by apes.
The next step would be when laughter was used for mock speech attacks … obviously only possible after the development of speech. But as the exchange of verbal insults is a common precursor to ancient battles, I’m led to consider that the speeches might have a similar purpose as the peacock’s feathers. In other words, two hominids would “speak” at each other to assess their fitness before engaging in battle. Intellect might sound an odd proxy for “fitness” to fight, but as a large brain is both needed for two legged movement and hand-eye co-ordination as well as for speaking, so being a capable speaker may be a very good way of telling those who had had the nourishment to create a big brain that is both good at speaking and good at co-ordinating body movements needed in fights. And it may not have been brute strength that won fights between hominids – but perhaps throwing accuracy.
In other words, just as males of many species as youngsters, practice physical sparring with their siblings, so a similar process could have been present with early humans. It may mean that these play “verbal sparring” started with something no more complex than a tuneful howl … but (because a large brain is not that expensive) might have rapidly led to the evolution of language – not because speaking was any use – but because complex vocalisation might have been a very good proxy signal of “fitness”.
However, alongside this, humour may have further developed, not as a mock fight, but as a means to convey social information … in other words, to educate others on the acceptable social boundaries of the society. This would have had a very strong bonding effect (reinforced by the endorphins? produced by laughter). Thus laughter from originally being important in proving a man’s fitness … may have quickly been adapted (often by women) to enforce social norms and allow much more complex social structures to develop … and perhaps be a way for women to instruct men in a non-confrontational way. And of course, speaking itself would have been a tool for social advancement within a group … and likewise using “mock verbal fights” as a way of gratifying others and a form of grooming of others.
To put it simply, a bit of slap stick comedy like pretend falling over … may have got the ladies (or gents) laughing and enabled the individual to increase their social standing and fitness for mating. And likewise, speech.
This would allow the same instinctual “that’s on the boundary of what I’d accept” laughter response, to have been adapted from the very simple “tickly/play-fight laughter response” of a rat through the “slap-stick” comedy appreciated by apes, to the more socially complex and diverse comedy we have today.