Introduction
Aggression, aggression
Aggression is omnipresent in both the animal kingdom and human society. Aggression is defined as any behavior directed toward another individual that is carried out with the intent to cause harm (Like animals, humans can also communicate aggression-related information, such as dominance and competition, through chemosignals. For instance, people are able to judge the personality traits of others based on their body odor such that there is a positive association between self-assessed dominance of odor donors and judgments based on their body odor by others (Although the search for human pheromone has not identified undisputed molecular components, previous research suggests that androstadienone (androsta-4,16,-dien-3-one) can be considered as one of the putative human sex pheromones. Androstadienone is present in male semen, axillary hair and the axillary skin surface (In the present study, we investigated the role of androstadienone in human aggression. Aggression is a heterogeneous concept, and here we distinguish two types of aggression, i.e. reactive aggression and proactive aggression (