Hereditary differences in social behaviour of male mice (Mus musculus L.)

Abstract

Pairs of sibling male mice, laboratory reared offspring of feral parents, were studied in one enclosure consisting of two boxes connected by a long runway. Two different patterns of social structure and spatial dispersion were observed: some males were highly intolerant of each other and established individual territories; other pairs peacefully shared the territory and its defence from intruders. From the analysis of their progeny, the behavioural differences proved to have a hereditary basis.