A journal called Aggressive Behavior has published research disputing the widely-held theory that boys will beat you up, whereas girls will talk behind your back. Actually, the study suggests, boys do both: In scientific terms, they are both "physically" and "relationally" more aggressive than girls.

The study followed 620 students of both sexes through middle school and high school in six Georgia districts, Time reports. Results came from regular surveys asking students about their behavior over the past 30 days.

Unfortunately, "almost all of the students surveyed, 96%, had passed a rumor or made a nasty comment about someone over the course of the seven-year study," a researcher says.

But physical and relational aggression were both more common in boys. Middle school, the study says, is the worst for meanness both physical and relational: It's most common between sixth and eighth grade.

But middle schoolers can look forward to high school, when it begins dropping toward a senior-year low. The researchers aren't the first to point to boys' emotional cruelty, the New York Times reports: The author of the book on which the movie Mean Girls is based wrote a sequel focusing on boys.

"The reality is that most boys’ days are filled with many of the same social challenges that girls face, and what they learn from those experiences matters now and for their futures, as it does for girls," writes Rosalind Wiseman.

(That advice could be handy for this family, whose first 12 kids were boys.)

This article originally appeared on Newser: Mean Girls? Boys Are Even Worse: Study

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