Figure 1.

Accumulation of new beneficial mutations by sexual (a) and asexual (b) populations in the case of extreme multidimensional epistasis. The number of loci L is 20, the population size N is 10⁶, the per locus mutation rate μ is 3 × 10⁻⁵, the advantage of an allele 1 a is 0.1, and the disadvantage of an allele 1 preceded by 0 d is 0.01. The average frequency of allele 1 at all of the loci (bold line, increasing), the variance in the number of alleles 1 per genotype (bold line, fluctuating), and the frequencies of allele 1 at individual loci (thin lines) are shown.