Why do Humans Smile?

[GrinningManiac]

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?

 

[Rylot]

Monkeys and other apes smile as well and since smiling is pretty universal regardless of language and culture it's probably rooted in our evolution from apes. As for why, I've no idea.

 

[eggy32]

I assume we don't use it to strike fear into others because humans wouldn't find that scary. Most people would notice large muscles and sharp weapons before they'd notice your teeth.

Anyway, we need some way of easily showing happiness and since we lost the use of teeth for fear, it got picked to be sued for happiness instead.

 

[grimsprice]

because we're stupid. I don't know.

What a silly question. You might as well ask why we laugh when something is funny.

 

[TheTaco007]

Why do we cry when we're sad/hurt?

Why do we yawn when someone else yawns?

Why does the fact that I even thought of yawning make me yawn?

Why do we say "first" on youtube videos?

 

[GrinningManiac]

Monkeys and other apes smile as well

Actually, when they do that, they're showing you their teeth to warn you that you're pissing them off. It's a dominance/threatening thing. Never smile at a gorilla.

What a silly question. You might as well ask why we laugh when something is funny.

I'm asking because we're the only (that I'm aware of) creature on earth that does this differently for seemingly no reason.

 

[Rarhnor]

I see where the OP is getting at.

What if smiling was replaced by farting?

And everycar had a chassis shaped as a duck...

OT: You smile to make me happy, and I smile to make you guys happy.

 

[Virus0015]

Why do we yawn when someone else yawns?
Why do we say "first" on youtube videos?

1: Not sure about that one but I know why when someone vomits you have an urge to vomit, really, it's believed to have stemmed back to hunting in groups.

2: Because some people are special.

 

[Necrofudge]

I dunno about you guys but I smile to show others that I am a threat. It doesn't work as well on people as it does on monkeys though...

 

[Luftwaffles]

Why do we cry when we're sad/hurt?

Why do we yawn when someone else yawns?

Why does the fact that I even thought of yawning make me yawn?

Why do we say "first" on youtube videos?

OOH i can answer the yawning.
When someone yawns, their eardrums pop combined with rapid intake of air, creating a partial difference in pressure(very tiny mind you), this difference effects our eardrums and thus, we yawn to equalise the pressure

 

[DefunctTheory]

Because teeth are not humans weapons, as they are with most animals. Our fist are, which is why something like clenching a fist is viewed as hostile.

In addition, humans are very visual animals. We've evolved to take notice of others facial expressions. Which is where all arguments fall to pieces anyway, as the snarl (Baring ones canines) is still known as an aggressive posture.

So really, the questions answer is: Humans still threaten each other with teeth, silly.

 

[Tharwen]

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].

 

[Sewora]

Fairly easy question to answer actually.

We smile because it's a remnant of pre-speech humanity. Why do children cry? Because they have no language, so they express themselves in the only way possible due to their inability to communicate. Smiling and crying are both means to convey emotions without words.

Displaying the teeth though is a tricky one. It might be a way to disarm eachother.

As for the Yawning thing. Humans are a flock animal, similar to lions. When one yawns it means things are calm and there's nothing to worry about, and the message continues down the line so everyone partakes in that particular piece of information.

The vomiting part is (Not something I've actually researched, but assume based on my currently possessed information): Most likely you feel the urge to vomit when someone else vomits due to the fact that we are flock animals, and therefore most likely retrieved our food from the same source. If one vomits, it might indicate that there's something wrong with the food and others expell the food to make sure none falls ill. Possibly as a means to defend a flock against diseases.

 

[grimsprice]

Monkeys and other apes smile as well

Actually, when they do that, they're showing you their teeth to warn you that you're pissing them off. It's a dominance/threatening thing. Never smile at a gorilla.

What a silly question. You might as well ask why we laugh when something is funny.

I'm asking because we're the only (that I'm aware of) creature on earth that does this differently for seemingly no reason.

why are we the only animals that go bananas over our own feces. True, cats bury theirs, but they aren't terrified of it, most creatures don't care, and some will even eat it if they so choose.

 

[Shampoo Ninja]

I go by my motto; If it doesn't help me in life by knowing, fuck it, I've got better stuff to think about it.

 

[HellsingerAngel]

We smile because we're omnivores.

Have you ever noticed the onyl reason most animals look creepy when they bare their teeth is because they're sharp? Also note that those naimals eat an abundance of meat. Smiling for them means "I'm going to eat you now!" or "I can tear your throat out!" because they have a menacing row of teeth.

Humans and smaller apes have flatter teeth, so the baring of teeth needed to be replaced (that's really just speculation). Our minds our set to see the facial curvature of those muscles as far more pleasent, most likely because of our teeth not having much in the way of intimidating stature. You'll also notice that people with far more pronounced cannine teeth are much more frightening when they smile, even if it is genuine.

 

[Angel_0A]

It could be evolved from snarling somehow... maybe.

Lots of animals show friendly recognition. Dogs wag their tails, cats squint their eyes.

 

[Cody211282]

Because we do.

 

[DefunctTheory]

Monkeys and other apes smile as well

Actually, when they do that, they're showing you their teeth to warn you that you're pissing them off. It's a dominance/threatening thing. Never smile at a gorilla.

What a silly question. You might as well ask why we laugh when something is funny.

I'm asking because we're the only (that I'm aware of) creature on earth that does this differently for seemingly no reason.

why are we the only animals that go bananas over our own feces. True, cats bury theirs, but they aren't terrified of it, most creatures don't care, and some will even eat it if they so choose.

Because we're the only ones who know whats in it.