A game theoretical model of the evolution of food hoarding: applications to the Paridae.

A game against the field is proposed that models the evolution of food-hoarding behavior in a group-living species, like many members of the family Paridae (Aves, Passeriformes). The model predicts that no special retrieval mechanisms (e.g., memory) are necessary for food-hoarding individuals to invade a population of nonhoarders, as long as the winters are very severe. Once food hoarding is established in a population, having smaller groups and separating foraging niches between group members prevent cheaters from benefiting from other individuals' caches. A scenario is proposed for the evolution of hoarding in the Paridae.