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Every once in a while I get an email that asks a compelling question. The one I received this week from a high school student did just that. The question is, “What is the most useless behavior that humans perform?”
For the most part all behaviors serve a purpose: We turn ventrally away from those that annoy us (distancing); we hold still (freeze response) when a snarling dog draws near to attenuate the dog’s chase response; our hairs stand up when frightened to make us look larger (we share this with all primates); and we massage our necks when mentally stressed to soothe tension. These behaviors are all useful in their own way. Those we can understand. But what about a “useless” behavior?
This one I had to think hard about and the only behavior that came to mind, although I am sure it is not the only one, is a tongue jut. In What Every BODY Is Saying (HarperCollins) I described tongue juts as the subconscious sticking out of the tongue, usually lightly clutched between the teeth, sometimes performed when someone is (1) caught making a mistake or a faux pas or; (2) when they are getting away with something. It came to mind as useless because I really don’t see the obvious need for this behavior, especially from the standpoint of survival.
Let me first differentiate the tongue jut from similar behaviors. In many cultures we know people will stick their tongue out to insult or to demonstrate their dislike. These are usually quite dramatic and of course intended to be seen – they are performed consciously. There are tongue pacifiers (rubbing the tongue against the lips to moisten lips or to relieve stress) teachers see on students on test day – especially on those who didn’t prepare. And then there is the tongue jut that neither insults nor relieves stress. But why?
There has to be a reason why we have passed this behavior along from one generation to another – even children born blind will perform this behavior despite having never seen it. Upon reflection the reason may simply be that it communicates an honest sentiment to others as my local car dealer found out.
After more than an hour of haggling over the price of a new car for my daughter, I asked if this was the absolute best price. He said it was and as he did so he did a tongue jut. Upon seeing that, I said, “no it’s not and you know it’s not.” And so we started negotiations all over again and this time somehow the car cost $700 less. Perhaps I might have said the same thing if I had not seen the tongue jut, but I doubt it. When I saw it, I was confident in my assessment that he was getting away with something; I had seen this behavior too many times in my previous life as an FBI agent.
I would love to have a perfect answer for this high school student but I don’t. There may be an evolutionary reason for this behavior that benefitted the performer as well as the observer, but I am not confident what the reason is – though that didn’t stop me from capitalizing on this silly, but perhaps not so useless behavior.
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Joe Navarro, M.A. is 25 year veteran of the FBI and is the author of the international bestseller What Every BODY is Saying, as well as Louder Than Words and Dangerous Personalities. For additional information and a free bibliography please contact him through Psychology Today: http://www.psychologytoday.com/blog/spycatcher or at www.jnforensics.com – Joe can be found on twitter: @navarrotells or on Facebook. Copyright © 2015, Joe Navarro
