From population structure to individual behaviour: genetic analysis of social structure in the European wild rabbit (Oryctolagus cuniculus)

The European wild rabbit (Oryctolagus cuniculus) lives in stable, territorial breeding groups, with male-biased natal dispersal, female philopatry, and a polygynous mating system. It was introduced into Britain in the 11 th century and kept in captive warrens as a food and fur resource. Populations expanded in the wild in the 18th century. Microsatellite markers were employed to examine the genetic structure of wild rabbit populations on three spatial scales: macrogeographic structure of 17 populations in East Anglia, microgeographic structure of a tagged population in the grounds of the University of East Anglia over four consecutive years, and pairwise kinships and individual movement within this tagged population. Populations across East Anglia were found to be genetically distinct, and heterozygote deficits were observed at all loci indicating sub-division within sampled populations. Analysis of the tagged population confirmed that rabbit populations are genetically sub-divided among social groups. Studying this population over four consecutive years revealed that as the population size increased, the number of social groups increased. Analysis of individual pairwise relatedness of females indicated that individuals did not necessarily group with kin, and behavioural data indicate that an optimum group size may exist which maximizes reproductive success.