The effect of bacterial recombination on adaptation on fitness landscapes with limited peak accessibility
byDanesh Moradigaravand, Jan Engelstädter
Research ArticleYear:2012
Extra Information
PLoS computational biology, 8(10) e1002735
Abstract
There is ample empirical evidence revealing that fitness landscapes are
often complex: the fitness effect of a newly arisen mutation can depend
strongly on the allelic state at other loci. However, little is known
about the effects of recombination on adaptation on such fitness
landscapes. Here, we investigate how recombination influences the rate
of adaptation on a special type of complex fitness landscapes. On these
landscapes, the mutational trajectories from the least to the most fit
genotype are interrupted by genotypes with low relative fitness. We
study the dynamics of adapting populations on landscapes with different
compositions and numbers of low fitness genotypes, with and without
recombination. Our results of the deterministic model (assuming an
infinite population size) show that recombination generally decelerates
adaptation on these landscapes. However, in finite populations, this
deceleration is outweighed by the accelerating Fisher-Muller effect
under certain conditions. We conclude that recombination has complex
effects on adaptation that are highly dependent on the particular
fitness landscape, population size and recombination rate.