Probability of rejecting the null hypothesis that HMGN3a sequences have evolved with the same pattern of substitution, as judged from the extent of differences in base composition biases between sequences (Disparity Index test). A Monte Carlo test (1000 replicates) was used to estimate the P-values, which are shown below the diagonal. P-values smaller than 0.05 are considered significant. The estimates of the disparity index per site are shown for each sequence pair above the diagonal. There were a total of 95 positions in the final dataset. None of the P-values were smaller than 0.05. All positions containing gaps and missing data were eliminated from the dataset. Black colored numbers: Probability computed (must be < 0.05 for hypothesis rejection at 5% level), Blue colored numbers: Disparity Index.