Figure 4From: Mutation accumulation in TetrahymenaPopulation mean fitness and variance for both empirical (solid marks) and simulated data (white marks) with bottleneck. Our model simulates the experimental conditions of bottleneck size of one individual, and a mean copy number of 45 for each MAC locus. At each generation copy number varies with probability 1-e-U, and fitness of an individual with z copies was assumed to be W(z) = exp(-s|z-zm|), where s is the selection strength against changes in copy number (z-zm). Simulated data in this figure shows results for s = 0.16, U = 1.5. B shows the log transformation of the mean fitness with the number of bottlenecks. Fit for the rate of decrease was y = -0.0752x + 0.0676; r2 = 0.976 for empirical data and y = -0.0761x + 0.0435, r2 = 0.9763 for the simulated data. Standard errors of the rate of decline were 0.005 and 0.003 respectively, which leads these two regressions not significantly different.Back to article page