Overview and Meaning
Mediated aggression is an agonistic interaction in which fighting is avoided. Mediated aggression is more commonly seen in laboratory settings than escalated aggression due to the already established social hierarchies within the home cage.
In this interaction one animal will back down in response to a threat before a full aggressive interaction results.
Mediated aggression normally represents the vast majority of mouse agonistic interactions, and is widely misinterpreted in the literature. In contrast, escalated aggression occurs when a subordinate responds to a threat behavior with an aggressive behavior, most typically an aggressive bite. Escalated aggression, as the name implies, escalates until one animal shows flight and submissive behavior, or, in a worst-case scenario, is killed or castrated. (Male mice attempt to castrate each other when they fight, and consequently withdraw their testicles into the body cavity during aggression).