Figure 5.

Pruned subtree of CesA clade and codeml branch-site tests. Branch lengths are proportional to substitutions per site. Postduplication branches with sites that codeml has identified as under significant positive selection are colored blue. Green branches indicate a sustained shift in selection pressure across all branches after a major gene duplication. Predicted gene duplication events are annotated as red dots. ω denotes dN:dS values. Sites with no differences in nonsynonymous substitutions yielded the PAML dN:dS ceiling ratio of 999. The overall dN:dS for the CesA clade is 0.08 (Fig. 3).