Debunking the myth of the 'mean girl,' scientists have found that boys use relational aggression - malicious rumours, social exclusion and rejection - to harm or manipulate others more often than girls.
Researchers from the University of Georgia followed a cohort of students from middle to high school and found that, at every grade level, boys engaged in relationally aggressive behaviour more often than girls.
A team led by professor Pamela Orpinas analysed data collected from 620 students randomly selected from six northeast Georgia school districts.
Students who participated in the study completed yearly surveys, which allowed the UGA researchers to identify and group them in distinct trajectories for relational aggression and victimisation as they progressed from grade six to 12.
"Overall, we found relational aggression to be a very common behaviour. Almost all of the students surveyed, 96 per cent, had passed a rumour or made a nasty comment about someone over the course of the seven-year study," said Orpinas, a professor of health promotion and behaviour in the College of Public Health.
Experiences of victimisation were found to be universal as well. Over 90 per cent of the students reported that they had been victims of relational aggression at least once.
The analysis found that students followed three developmental trajectories of perpetration and three similar trajectories of victimisation - low, moderate and high declining (that is, very high in middle school and declining in high school).
When examining how these trajectories differed by gender, the data showed some unexpected results.
Significantly more boys than girls fell into the two higher trajectories for relational aggression perpetration, while more girls than boys fell into the two higher trajectories for victimisation.
"We have books, websites and conferences aimed at stopping girls from being aggressive, as well as a lot of qualitative research on why girls are relationally aggressive," Orpinas said.
"But oddly enough, we don't have enough research on why boys would be relationally aggressive because people have assumed it's a girl behaviour," Orpinas said.
While the study may call for more scholarship on "mean boys" and why they behave the way they do, Orpinas said, the findings ultimately emphasise a need to include boys and girls equally in programmes aimed at reducing relational aggression.
The study was published in the journal Aggressive Behavior.