Hamiltonís Rule Applied to Reciprocal Altruism

Jeff Fletcher and Martin Zwick.

Proceedings of the IEEE Congress on Evolutionary Computation, Portland, Oregon 2004.


Reciprocal altruism and inclusive fitness are generally considered alternative mechanisms by which cooperative, altruistic traits may evolve. Here we demonstrate that very general versions of Hamiltonís inclusive fitness rule (developed by Queller) can be applied to traditional reciprocal altruism models such as the iterated Prisonerís Dilemma. In this way we show that both mechanisms rely fundamentally on the same principleóthe positive assortment of helping behaviors. We discuss barriers to this unified view, including phenotype/genotype differences and non-additive fitness (or utility) functions that are typical of reciprocal altruism models. We then demonstrate how Quellerís versions of Hamiltonís rule remove these obstacles.