There is evolutionary significance to the petty acts of aggression that were famously portrayed by Lindsay Lohan and other young women in the 2004 film Mean Girls. Women resort to this behavior in order to reduce competition for sexual rivals, and they form alliances in order to reduce the risk of retaliation.

Writing in the journal Philosophical Transactions of the Royal Society B, author Paula Stockley points out that "although female aggression takes diverse forms, under most circumstances relatively low-risk competitive strategies are favoured.”

Women, however, do not exactly have a monopoly on meanness.

According to the evolutionary psychologist and co-author Anne Campbell, "there is virtually no sex difference in indirect aggression." Professor Campbell told Live Science, "By the time you get to adulthood, particularly in work situations, men use this too.”

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