Genome-wide relationships between log(ω) and log( ρ ) for eight pairwise comparisons. Each column reports the details of the genome-wide comparison between human and the indicated species. Below each species, the number of orthologous protein pairs obtained from Ensembl (N) and the number of pairs retained after exclusion (n) are shown. The squared correlation coefficient (R2) between log(ρ) and log(ω) is shown and plotted in red. The R2 between log(Ka
) and log(Ka) is plotted in blue. The R2 values between log(ρ) and log(ω) obtained for each of 100 genome-wide permutations are plotted in black. The observed values are uniformly larger than those obtained via permutation.