Figure 4.
(A) Retrotransposon insertions that generate piRNAs (piRT insertions) have a higher probability of fixation or of attaining high frequency in the population because of their relatively advantageous effects. (B) Retrotransposon insertions that are repressed by piRNAs (targetRT insertions) also have a higher probability to be fixed or attain high frequency, because their deleterious effects are (partially) alleviated by piRNAs. (Ne = 500, a = 0.001, b = 0.0005, r = 2.5 × 10−8, u1 = 0.01, v = 0, after scaling for all four scenarios; u2 = 0.01, 0.001, 0.0001, and 0.00001, after scaling for scenarios I–IV, respectively, for both A and B.)