The role of submissiveness in isolation induced intermale fighting in mice.

Male mice isolated for either short or long time periods were paired in 10 min standard opponent tests with group-housed opponents with either 10 previous defect experiences or no previous defeats. The results show the defeat experience increases the animal's readiness to assume and maintain submissive postures and that these postures in turn effect both the number of attacks and tail-rattles of the aggressor. Submission, once learned, was shown to be a more or less permanent change in behavior, resistant to the aggression-producing effects of isolation.