Children adjust behavior in novel social environments to reflect local cooperative norms inferred from brief exposure

Stark intergroup variation in prosocial behavior, as elicited with economic experiments, is evident even though humans are highly mobile. Conformity to local norms has been posited to play an integral role in the maintenance of this variation. Experiments suggest that adults indeed rapidly infer pro- and antisocial norms in a new or changed social environment and adjust their behavior to reflect the inferred norms. Studies of the ontogeny of prosocial behavior show that by middle childhood, children’s prosocial behavior conforms to that of local adults. Furthermore, by this stage, children are susceptible to the manipulation of explicit normative information. However, as yet unknown is whether children concomitantly have the propensity to 1) rapidly infer local cooperative norms in a novel, realistic social environment, 2) extend these inferences to norms for unobserved behaviors, and 3) apply the inferred norms in the same environment. Here, we used a slideshow to introduce children (age nine to eleven) to a novel social environment, Neighborhood X, which differed by condition (Prosocial or Antisocial). We measured perceived cooperative norms in children’s Own Neighborhood and in Neighborhood X via questionnaires; norms for Neighborhood X diverged drastically dependent upon condition, a result robust to the exclusion of questions about norms for unobserved behaviors. Children’s perceived cooperative norms in Own Neighborhood predicted their prosocial behavior (Dictator Game) in Own Neighborhood. Moreover, even though information about giving behavior was not presented in the slideshow, inferred norms for Neighborhood X predicted children’s prosocial behavior in the same milieu. Changes from baseline prosocial behavior, as measured with a separate helping task, did not extend beyond Neighborhood X. Our results are consistent with the hypothesis that humans have a propensity to rapidly infer and conform to local cooperative norms, thus maintaining group differences in prosocial behavior, and further indicate that this propensity is in operation by middle childhood.