CARBONDALE -- On the dance floor at Gatsby's II, a popular bar at Southern Illinois University in Carbondale, a tall brunette drinks beer from a plastic pitcher while she grinds her backside into a man's body. A silver disco ball hangs overhead while a blond woman in a pink, pleated miniskirt writhes on her partner's leg. A girl notices that her boyfriend's attention is wandering. With a manicured hand, she grabs his face and plants a Hollywood-worthy kiss on his mouth. On this sticky dance floor, littered with plastic cups and packed with gyrating bodies, women are the hunters as...