^aClassification of topologies and branches following that in Figure 1. FSGD, fish-specific genome duplication.

^bNumber of cases where the model A with foreground ω₂ > 1 is significantly more likely than the model A with ω₂ = 1.

^cω₀, the purifying selection pressure, has the same value for foreground and background branches; only the proportion of sites under ω₀ varies.