Fig. 5.

Accumulation of deleterious substitutions in the absence of beneficial mutations. Parameters (unless otherwise stated): N = 1000, n = 50, $\mu d={10}^{-7}$, a concave down fitness function, and b = 25 (relaxed transmission bottleneck) or b = 5 (tight transmission bottleneck). UPI: uniparental inheritance with a relaxed bottleneck, UPI (bot): uniparental inheritance with a tight bottleneck, BPI: biparental inheritance with a relaxed bottleneck, and BPI (bot): biparental inheritance with a tight bottleneck. (A) Comparison with free-living genomes (linear fitness function for both free-living and cytoplasmic genomes, $s_d=0.1$, and s_FL = 1). (B) Mean deleterious substitutions per cytoplasmic genome for $s_d=0.1$. (C) Mean deleterious substitutions per cytoplasmic genome for $s_d=0.01$. Error bars are ± standard error of the mean.