Mechanisms of sibling recognition in meadow voles

Abstract

The purpose of this study was to determine whether sibling recognition in meadow voles (Microtus pennsylvanicus) resulted from familiarity through common rearing or from identification of kin via phenotype matching. The first experiment clearly demonstrated that sibling recognition occurs among meadow voles. Individuals preferred the odor of familiar siblings to the odor of unfamiliar nonsiblings, and agonistic acts were less frequent between sibling than between nonsibling dyads. The second experiment examined whether sibling recognition resulted from familiarity and genetic relatedness. Meadow voles preferred the odor of littermates to the odor of nonlittermates. Full siblings do not share olfactory cues or signatures unique to that litter. Meadow voles behaved agonistically toward unfamiliar full siblings, but not toward familiar nonsiblings. Reduced agonistic behavior between and preferences for littermates versus nonlittermates, independently of genetic relatedness, suggest that among meadow voles sibling recognition is based on prior association through common rearing.