Clade asymmetries in families with duplications. Clade asymmetry (A) in relative substitution rate (top), absolute change in polarity (middle) and exchangeability (bottom) by molecular function. Molecular function category means were calculated by unweighted averaging over families. One-way ANOVA, respectively: F = 3.91, P < 0.00001; F = 7.63, P < 0.00001; F = 2.99, P < 0.001. Different letters signify categories different by Tukey-Kramer test, P = 0.05.