Yes agree. There are plenty of cultures around the world where making direct eye contact with a 'superior', or someone older than you is disrespectful. Indigenious people from Arnhem Land Australia will signal their intention to speak with you by standing off to the side of your peripheral vision and then wait for you to approach/invite approach. Any first year anthropology student knows that human social behavior is never universal...

It's also 'disrespectful' (I'm anthropomorphising wildly) to a lot of animals. Try staring a dominant dog in the eye and see what it gets you.

It seems like a smile is pretty close to universal, though. Maybe you can tell me in which cultures it means something different?

Smiling might be universal across humanity but the emotional state and intent of the smile is not. For example, in some cultures, smiling/grinning is a response to embarrassment. When I was travelling in China I asked a old man for directions (in mandarin)...he was so shocked that a foreigner was speaking with him he couldn't speak back. He grinned from ear to ear though.

Also, in primates, smiling is very closely related to baring of teeth. Smiling = 'let's be friends'. Baring teeth = 'come any closer and I'll kill you'. I would not like to make that kind of miscalculation when meeting an alien for the first time....

> For example, in some cultures, smiling/grinning is a response to embarrassment.

I'd have to ask, then, where is that not true? I know that happens in the USA and a friend of mine from Japan also does that.

Everyone smiles, but for slightly different reasons. North Americans often smile to appear polite, which makes the rest of the world think we're weird (cause forced smiles never reach the eyes).

Spontaneous smiles activate the major cheek muscles (pulling the lips up), as well as the muscles just around the eye. Forced smiles only activate the cheek muscles (it's apparently nearly impossible to consciously activate those eye muscles).

There's also questions of degrees of smiling, as in amount of teeth.

It is not impossible, one just needs to actively learn to use the muscles around the eyes to make real-looking smiles. Takes a few years of sporadically applied effort though.

I had a Russian professor (teaching the language, and from the country) in college who mentioned one day in class (I forget how we got onto the subject) that Americans smile a lot more than Russian people, and that it generally seemed false and insincere to her. I've had other Russians confirm this, though they generally tend to be older.

…especially since they might not have eyes.

... or even bodies for that matter.

You have to have some form of body, no?

Yeah. Try expressing good manners to fish... It might be a mammalian thing, but I doubt it goes outside that.