Why does a guy think it is funny to fart on his girlfriend, and make a joke out of it?

It does seem like guys are more into farts and fart jokes than women are, doesn't it?
Who knows why? I am one of those people who thinks that a lot of human behavior is primeval, so maybe it goes back to (sorry) butt sniffing. Many animals, and we are animals, sniff various body areas to get an idea of where they have been, what they ate, who they were with, and what else they did. We supposedly have replaced all that with language. But no one ever accused a lot of men of being great communicators. They'd rather have beer drinking contests and argue over football, and that's how they find out all they need to know - who's stronger, bigger, and smarter.

Wow... I had to snicker at that... but I guess my real question is... does he LIKE ME A LOT... or is he trying to make me think he is a cave man? LOL!

Who knows... maybe they go hand in hand.

Because culture tells them it's masculine or manly to be/do disgusting things. -- It's the opposite of how women are taught to be.

I don't know. I think it's rather crude and I'd tell him to stop. Ask him why he does it.