The Social and Genetic Structure of a Natural Colony of House Mice, Mus musculus, at Healesville WildlifeSanctuary

Abstract

A 2-year program monitored the spatial organization, genetic structure and turnover rate of an unconfined commensal colony of mice. Four demes (social breeding units) were identified; each usually consisted of one or two males and two or three females. Demes were detected simultaneously in adjoining cages of an aviary (one deme per cage). Movement between demes was rare and the life span of a deme ranged from 2 to 7 months. The adult members of each deme had genotypes compatible to the majority of the young captured in the respective cage of the aviary at the time of residence of the deme. Taken in isolation, these results suggest that social behaviour would have a major impact on the genetic structure of the aviary population. When viewed over the main breeding season, the short life span of a deme and the genetic differences between demes indicate that social organization probably had only a temporary effect on the genetic composition of the aviary population.