Affiliation and aggression in rats

The relationship between affiliation and aggression was examined in two experiments. In the first study, each of 12 male albino rats was allowed to choose in a T-maze between two alternatives. One alternative housed a more aggressive target male and the other housed a less aggressive target male. The subjects preferred the less aggressive target animal. A second investigation allowed each of 36 male albino rats to choose between a target animal and an empty compartment. The results were that all the subjects preferred to affiliate with the target animal. However, as the level of aggressiveness by the target animal increased, the level of gregariousness decreased. The data suggest that an important determinant of affiliation is the behavior, and specifically the aggressiveness, of the target animal.