What's beef?

" I wanna make luv in this club" ... Usher sings out of what seems to be a million speakers scattered around the dance floor, people start going wild busting out their baddest moves , then the music seems to fade, guys n girls stop throwing the random punch that is dance, and there she is... This chic in the micro-est mini I ever did see, with a top so tight I could swear I saw her heart beating.. And a single sentence from some tiny voice(fair to assume is female) "who invited the slut?! "

To borrow a phrase from the late, great Notorious B.I.G "What's Beef?"

Wait, what's that i hear like blatant denial?Ladies, act like you know! We're always hating on each other, even though we might have never met... IT'S CRAZY!!! Woman on Woman crime is at an all time high, women divers are less courteous and patient to thier counter-parts, walk into a shop and a female attendant will be less helpful if you are of the same gender. Again, i reiterate, IT'S CRAZY!!!!

Here's what some people had to say when i threw it out there:
I believe you have an acceptable answer to your question tucked away in your brain somewhere. However, the strongest contributor to this behavior is feelings of competition. Zeb(Male 27)

They don't, overall. Please don't over generalise. Women are not more likely to be petty to one another than men are.
Why "people" act petty can change depending on the situation, i.e. they might be petty only towards certain people they don't care about, because they dislike that person, because they are insecure, because it makes them feel more powerful to treat people this way, because they have benefited from this behavoir in the past, etc.
J(Female, 34)

Girls, we're all on the same team so to borrow yet another phrase, from one of the greatest men of all time "why can't we all just get along?"

(poll culled from yahoo! answers)