Why Laugh, what purpose does it have in the evolutionary scheme of things, surely a smile is good enough?

I wonder what the train of events was that lead to the first laugh and why it is so important to give happiness a sound, maybe because there were a lot of blind cavemen about?


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'I'd rather have a bottle in front of me, than a frontal labotomy'
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y asks:
"Why Laugh ....?"

Bonobos laugh ... chimpanzees laugh. Laughter likely preceded cavemen by tens of millions of years.

Is laughter associated with happiness?

We seem to laugh under all sorts of stimuli - nervousness, the misfortunes of others...

Ok!

What function does laughter perform (that is useful in the evolutionary scheme of things)that a smile cannot?

get attention

La tendere mercies,,, unaggressive bottled tensions/energy release~

Would laughter (in its purest form) be classed as a reflexive reaction to stimulli, or as a more controlled thought based reaction.

IMHO, I think it's a reflexive reaction; I don't have to think about laughing, I just do it. If I think about laughing, I can't laugh; I can't make myself laugh deliberately. Sometimes I laugh when I think about funny things, but I have to feel the humor of the situation. Sometimes I laugh when I'm nervous, or I try to make other people laugh when I'm nervous. It takes the edge off the tension in the situation for me.