2013

Purpose. Low heart rate has been linked to antisocial behavior. However, the effect of low heart rate may be mediated by affiliation with bullies. We hypothesized that individuals with low heart rate are more likely to affiliate with bullies and in turn are influenced by these peers. Method. Data come from two waves of a subsample of the TRAILS study (N=809; 44.0% boys; mean age 11.0 at T1 and 13.5 at T2). Antisocial behavior was measured via the Antisocial Behavior Questionnaire at both waves. Heart rate was assessed during rest at T1. Affiliation with bullies was assessed via peer-nominations at T1. Possible gender differences were taken into account and all analyses were adjusted for family context (i.e., family break-up and SES). Results. Regression analyses showed that lower heart rate was only associated with antisocial behavior in (pre)adolescents who affiliated with bullies. Moreover, the effect of lower heart rate on boys’ antisocial behavior went partly via affiliation with bullies. Conclusions. Our findings show that (pre)adolescents, and in particular boys, seem to be in environments that match their biological disposition and in turn are shaped by this environment.

The moderating effects of three specific conditions (status hierarchy, attractiveness hierarchy, and sex ratio) on the link between status (popularity) and physical and relational aggression were examined in a large sample of adolescent boys (N = 1,665) and girls (N = 1,637) (M age = 13.60). In line with the hypotheses, derived from integrating a goal-framing perspective with an evolutionary perspective, it was found for boys that status was more strongly related to both physical and relational aggression in classrooms when differences in status (status hierarchy) and physical attractiveness between same-gender peers (attractiveness hierarchy) were smaller, and to relational aggression when cross-gender peers (potential mating partners) were relatively scarce. For girls, status hierarchy and attractiveness hierarchy only moderated the link between status and relational aggression. These results suggest that competition to a certain extent triggers aggression by high status adolescents. The findings are discussed from a broader evolutionary perspective, and the utility of this approach for understanding adolescents’ behavior in the peer context is considered.