Why do Humans Smile?

[Redlin5_v1legacy]

To show our emotion without using words. A physical response, like a dog wagging its tail.

That is what I think anyway.

 

[Sewora]

To show our emotion without using words. A physical response, like a dog wagging its tail.

That is what I think anyway.

Correct. Although a dog wagging it's tail doesn't necessarily mean it's happy. That's just a common interpretation by humans trying to apply human emotions unto animals.

 

[Keava]

We still retained the ability snarl like the animals that show their teeth as a warning. Also, the closest to us, chimpanzees, smile more in form of showing fear rather than as a warning.
I suppose we smiled to avoid danger, showing our fear allowed us to survive, because the other human knew that sign and knew that he already won. Over years it just naturally evolved into expression of happiness.

 

[Redlin5_v1legacy]

To show our emotion without using words. A physical response, like a dog wagging its tail.

That is what I think anyway.

Correct. Although a dog wagging it's tail doesn't necessarily mean it's happy. That's just a common interpretation by humans trying to apply human emotions unto animals.

I know that, I've seen a dog attacking a child while wagging its tail. I was just using it as an example as a physical movement triggered by an emotional/behavioural stimulus.

 

[chromewarriorXIII]

I expect there wasn't a suitable bit of body vocabulary for expressing contentment, so we evolved to replace the aggressive 'smile' with a friendly one. Also, I'd say we still find smiles [a href="http://www.youtube.com/watch?v=9tD4dTIT4Ac"]at least slightly threatening[/a].

Haha, there are at least 3 comments in that video complaining about clicking links on here. I thought it was really cool though and it was more of a subtle horror rather than a "Boo!" jump out and scare you.

As for the whole smiling thing, I think it's sort of ingrained into our DNA, even babies will smile when they are happy and that's at an age where they can't really do much. As for how we developed that, I'm not really sure.

 

[fletch_talon]

I know that, I've seen a dog attacking a child while wagging its tail. I was just using it as an example as a physical movement triggered by an emotional/behavioural stimulus.

The child probably deserved it.
I'd be wagging my tail too if I had the chance to maul the little bastard that was yanking on my ears.

 

[unoleian]

What's even more interesting, is to consider the range of what might be considered "smiling," and the different connotations carried by subtle shifts in expression.

Spoiler: This image submitted for your consideration

Each could be called a smile, but each one certainly expresses a different feeling altogether. What's interesting is that the one with the mouth most open is possibly the most disarming. It's strange indeed that this is counter to what we seem to understand about most of the rest of the natural world.

We close ourselves off the more we close our face. The more open it becomes, the more receptive we are.

 

[jamesworkshop]

Not as in "Why are we happy" but "why do we show our teeth to show positive emotions"?

Every other animal on the earth bares their teeth to show strength, to threaten and to warn others not to bug them, because they swear to god if you touch them they will rip your arms off.

But humans bare their teeth when they hear a funny joke or are generally happy. Why is this?

What are your theories, and do you show your teeth/have you seen someone show their teeth like this for a reason other than happy emotions? have they actually used it to threaten someone?

Actually large displays of teeth are generally considered to be non genuine smiles most smiles do not normaly display both rows of teeth fully

genuine smiles involve the muscles around the eyes, producing crows' feet around the corners, whereas a fake grin only involves the mouth.

left genuine, right fake


The aggressive display is much more about eyebrow shape than teeth visability