mutation accumulation may only be a minor force in shaping life-history traits, even when reproduction is sexual突变积累可能只是一个小小的力量在塑造生活史特性,即使复制性.pdfVIP

Mutation Accumulation May Only Be a Minor Force in Shaping Life-History Traits, Even when Reproduction Is Sexual ´ 1 2 Maciej Jan Danko *, Jan Kozłowski ´ 1 Max Planck Institute for Demographic Research, Rostock, Germany, 2 Institute of Environmental Sciences, Jagiellonian University, Krakow, Poland Abstract In a previous theoretical study we investigated whether adaptive or non-adaptive processes are more important in the evolution of senescence. We built a model that combined both processes and found that mutation accumulation is important only at those ages where mortality has a negligible impact on fitness. This model, however, was limited to haploid organisms. Here we extend our model by introducing diploidy and sexual reproduction. We assume that only recessive (mutated) homozygotes experience detrimental effects. Our results corroborate our previous conclusions, confirming that life histories are largely determined by adaptive processes. We also found that the equilibrium frequencies of mutated alleles are at higher values than in haploid model, because mutations in heterozygotes are hidden for directional selection. Nevertheless, the equilibrium frequencies of recessive homozygotes that make mutations visible to selection are very similar to the equilibrium frequencies of these alleles in our haploid model. Diploidy and sexual reproduction with recombination slows down approaching selection-mutation balance. ´ Citation: Danko MJ, Kozłow