Population genetic theory of kin selection. II. The multiplicative model.

Abstract

Analyzes multiplicative kin selection models incorporating fitness functions which involve products of the costs and benefits that are associated with altruistic actions. Multiplicative models exhibit a number of qualitative differences compared to additive models including the dependence of gene frequency change on a more complex covariance and the existence of strongly noninvasible fixation states associated with intermediate levels of performance of altruism. By regarding the multiplicative model as an additive model with genotype-dependent benefit parameters, the multiplicative model can be reconciled with Hamilton's theory. -Authors