Evolutionary divergences between mouse and human orthologous genes measured by (A) nonsynonymous distance (dN), (B) synonymous distance (dS), (C) dN/dS, (D) dN controlled for tissue specificity, (E) expression-profile distance from GeneAtlas data, (F) expression-profile distance from ExonArrays data, and (G) expression-profile distance from GeneAtlas data controlled for tissue specificity. Error bars show one standard error of the mean. P values are from a Mann–Whitney U test. Morpho, morphogenes; noness, nonessential; physio, physiogenes.