| Abstract: | Six male mice placed in a large, moderately complex enclosure formed a stable dominance hierarchy in which two mice defended adjacent floor areas and the remaining four mice were subordinate and did not form territories. Intruder mice with winning or losing experience in prior paired encounters, or those with no fighting experience, were introduced individually into the colony for 30 minute periods. These intruders were attacked by the dominant members of the colony, and the fighting outcomes were strongly dependent upon the fighting experience of the intruder. Intruders with losing or no fighting experience engaged in little mutual fighting with residents, were easily defeated, and terminated attacks by engaging in subordinate behaviors. Intruders with winning experience fought vigorously with residents, attacked and, in many cases, defeated residents. These results suggest that relatively little winning experience gained in earlier paired encounters may be sufficient to overcome the various fighting advantages enjoyed by a dominant territorial holding member of a colony. |
