With increased media use, the research interest in media violence and its effect on behavior is also increasing. It is often reported that people watch aggressive acts on television and acquire...Show moreWith increased media use, the research interest in media violence and its effect on behavior is also increasing. It is often reported that people watch aggressive acts on television and acquire this behavior through for example observational learning. Multiple theories suggest that an interplay between person, situation, environment, and biology is accountable for the effect of media violence on behavior. However, investigating this topic in humans is often neither convenient nor ethical. Due to existing genetic and cognitive similarities between humans and chimpanzees, it is possible to do this research in captive chimpanzees. This study investigates the effect of media representations of conspecific aggression on chimpanzee behavior and how this relationship changes over time. Three observers focused on one individual and observed him for four months. Data was categorized into three conditions: test (aggressive stimuli), control (non-aggressive stimuli), and control-control (no stimuli). It was expected that the chimpanzee would show more aggressive behavior on test days compared to non-test days and that this display would increase over time due to desensitization. However, Kruskal-Wallis F-tests revealed no such significant differences for aggressive behavior, and no effect of time was found for this relationship. Therefore, the hypotheses were not supported by the data. It appeared there was no effect of viewing videos of conspecific aggression on chimpanzee behavior. The lack of significant findings might be due to a lack of power, the complexity of interactions described by multiple theories, and methodological issues. This research contributes to the theoretical framework, poses new challenges for future research, and provides implications for policy on media use.Show less