Dominance, territoriality and social organization in the white rhinoceros

The classical definition of territoriality in terms of defense of an area is misleading, at least for mammals. It obscures the subtle variability in spatial patterns observed and hampers consideration of evolutionary functions. This is illustrated by the results of a field study of the white rhinoceros carried out by the author in South Africa. In the white rhinoceros, dominant males maintain mutually exclusive ranges, but share these with individual subordinate males. Female home ranges overlap widely. Set interaction patterns between males preserve the spatial dominance relationship without driving another male from the territory. Dominance is revealed when other males do not contest rights to an estrus female. Food resources are readily shared, and the system does not regulate population increase. Rather, it serves to organise competition for reproductive opportunity among males, selecting out prime males without hampering their efficiency. These conclusions give insight into social patterns in oilier species.