1 research outputs found
The Baldwin effect under multi-peaked fitness landscapes: Phenotypic fluctuation accelerates evolutionary rate
Phenotypic fluctuations and plasticity can generally affect the course of
evolution, a process known as the Baldwin effect. Several studies have recast
this effect and claimed that phenotypic plasticity acceler- ates evolutionary
rate (the Baldwin expediting effect); however, the validity of this claim is
still controversial. In this study, we investi- gate the evolutionary
population dynamics of a quantitative genetic model under a multi-peaked
fitness landscape, in order to evaluate the validity of the effect. We provide
analytical expressions for the evolutionary rate and average population
fitness. Our results indicate that under a multi-peaked fitness landscape,
phenotypic fluctuation always accelerates evolutionary rate, but it decreases
the average fit- ness. As an extreme case of the trade-off between the rate of
evolution and average fitness, phenotypic fluctuation is shown to accelerate
the error catastrophe, in which a population fails to sustain a high-fitness
peak. In the context of our findings, we discuss the role of phenotypic
plasticity in adaptive evolution.Comment: 12 pages, 10 figure