Figure 4

Effect of sequence divergence on posterior ω. Posterior ω values were computed for cases where at least one site had a high (>0.95) probability of belonging to the ω >1 category. Results are averages over 5 independent replicates. Open circles represent situations where no site was identified in any of the five replicates. Despite a slight underestimation of posterior ω values (parametric value = 1.754; horizontal dashed line), there is no evidence that saturation of divergence alone could have caused the lower ω found in A. halleri and A. lyrata than in Brassica.