Figure 2.

Adaptation profiles for sexual and clonal host populations at two host-mutation rates. (a) Population size, N = 100; μh = 10-6 bits/allele/generation; μp = 10-8-10-3 bits/allele/ generation; number of loci, L = 10. Black curve = sexual population; red curve = clonal population, both under the same steady-state conditions. The value of μp/μh is progressively increased in each curve by increasing μp at constant μh. The figure shows that the rate advantage accruing to sex in the adoption of advantageous mutations persists in temporally complex environments when numerous allelic species are in play and there is potentially more than one mutation occurring in each generation. (b)N = 100; μh = 10-3 bits/allele/generation; μp = 10-6-10-2 bits/allele/ generation; number of loci, L = 10. Black and red curves as in (a) above. The green curve represents the adaptation score for the sexual population adjusted by a factor of 0.5 to reflect its lower fitness relative to the clonal population due to the 2-fold cost of males. (c)N = 3000; μ = 10-6 bits/allele/generation; μp = 10-8-10-3 bits/allele/ generation; number of loci, L = 10. Black and red curves as in (a) above. The data are similar to those in (a) above but the larger population has produced a slightly larger difference in steady-state adaptation scores for sexual and clonal populations. (d)N = 3000; μ = 10-3 bits/allele/generation; μp = 10-6-10-1 bits/allele/ generation; number of loci, L = 10. Black and red curves as in (a); the green curve as in (b) above. The clonal population is also subject to interference with selection, due to increased polymorphism at the high mutation rate. This interference serves further to reduce the adaptation score. Standard Errors of the Mean are approximately the width of the line connecting the data points.

Green and Mason BMC Evolutionary Biology 2013 13:174   doi:10.1186/1471-2148-13-174
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