After numerous studies, its has been concluded that humor has nothing to do with nature, and much to do with nurture. There is no "humor" gene that defines our sense of humor or our appreciation for different kinds of humors. These studies were conducted with identical twins, who most of the time don't share a common sense of humor (which they should if were going by the genetic theory).
But, I also read an article - you guys will get a kick out of this one, I promise
- that Brit
humor in particular does actually have some genetic linkage. Brit humor is a result of genetic and environmental influences. I'm not exactly sure on how this genetic linkage works, but we all know that Brits are more appreciative of "negative" humor - such as teasing, racism, and sexist humiliation, all of which are considered, by some Americans, to be aggressively sarcastic and degrading. Anyways, regardless of what side you're on, its obvious that American humor and Brit humor are worlds apart. Steve Carell's character in The Office is supposedly much less insensitive in the UK version of the show. Anyways, The Office - regardless of which version - is not my cup of tea at all!
Humor appreciation is actually a cognitive thing. There is a region in our brain - the anterior frontal lobe- that defines our sense of humor. If this part of the brain is damaged, humor appreciation is impaired. What's really interesting is that people who's anterior frontal lobes are damaged only respond well to slapstick humor, and have less to no appreciation for any other kind of humor.
Coming down to the differences between men and women- there is a difference between the style of humor men and women appreciate and initiate. There's a theory out there that suggests that men are generally funnier than women because of higher levels of testosterone in the male body. (Weird, right?) Initially, as a young boy who just hit puberty, guys get aggressive. Later, that aggressiveness "matures", if you will, and turns into wit. Anyways, just a theory, but definitely plausible.
There are also claims that men are generally funnier because of their role in society - because they have to woo women, make friends, etc (although I don't understand that at all since its also true for women) and because "patriarchal society" prevents women from opening up and being herself in society. Which again I find a load of bull - sounds like some feminist agenda hidden behind this theory that makes me roll my eyes!
I don't think its true that women, in general everyday places, can't be funny or extroverted or outgoing, but I honestly cannot stand female stand-up comedians. They don't make me laugh at all!
I think its the whole yin-yang situation at work here. If its true men are funnier, it is also true that women are the one who laugh a lot more than men do, so perhaps the have a greater appreciation of humor? Who knows.