Don'T fall off the adaptation cliff: when asymmetrical fitness selects for suboptimal traits.

ABSTRACT: The cliff-edge hypothesis introduces the counterintuitive idea that the trait value associated with the maximum of an asymmetrical fitness function is not necessarily the value that is selected for if the trait shows variability in its phenotypic expression. We develop a model of population dynamics to show that, in such a system, the evolutionary stable strategy depends on both the shape of the fitness function around its maximum and the amount of phenotypic variance. The model provides quantitative predictions of the expected trait value distribution and provides an alternative quantity that should be maximized ("genotype fitness") instead of the classical fitness function ("phenotype fitness"). We test the model's predictions on three examples: (1) litter size in guinea pigs, (2) sexual

SUBMITTER: Vercken E 

PROVIDER: S-EPMC3324540 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature