Testing the Kinship Theory of Intragenomic Conflict in Honey Bees (Apis mellifera)

Strong support for the theory of kin selection can come from predicting outcomes under circumstances of within-family conflict. Genes inherited from mothers (matrigenes) and fathers (patrigenes) usually work harmoniously in the offspring. However, kin selection theory predicts these genes may be in conflict over interactions among relatives where they are unequally represented (half-siblings). In honey bees, patrigenes are predicted to favor daughters that lay eggs themselves rather than remaining sterile and rearing their half-sisters'' offspring. We tested this prediction using hybrid workers from 18 male-female crosses. Workers displayed the reproductive characteristics of their paternal genomes, patrigene expression was higher in reproductive tissues, and this patrigene bias increased in reproductive workers. These results provide strong empirical support for kin selection theory.