Perhaps they were not trying to be one of the guys, perhaps they were just as bloodthirsty and cold hearted as the men? It may well be that both sexes, being human is a condition they both have, and that those are human traits. Its just that they have historically prevented from showing it, and when the restraints come off, the behavior comes out. Violent crime as a whole has gone down in the US since the early 1990s, but woman on women violence, particularly in juvie courts, is off the charts in the same period. Are women today more violent then in the past, or do they just have more opportunities to express themselves in a violent manner?
PhD level research question to be sure.
Not that anyone would ever let me, but .... if I repeated the Stanford Prison Experiment with only women, does the outcome change?