The social consequences of honey bee polyandry: the effects of kinship on worker interactions within colonies

Abstract

Honey bees, Apis mellifera L., are polyandrous and several males simultaneously father offspring within a single colony. The relatedness of female colony members therefore varies with their paternity: workers encounter both patrilineal full sister ( r¯=0·75) and non-patrilineal half-sister ( r¯=0·25) nestmates. The impact of this intra-colony genetic variation on social grooming and trophallaxis (liquid food exchange) among workers in colonies consisting of two phenotypically-distinct worker patrilines was examined. Workers in these colonies groomed and fed a disproportionately large number of full sisters despite a tendency to encounter a disproportionately large number of half-sisters. Thus, workers actively discriminated between full and half-sisters. This patrilineal discrimination occurred both in colonies with laying queens and in a queenless colony rearing replacement queens. These results suggest that intracolony genetic variation may have a major effect on colony social organization.