Figure 2.
Relative rates of point substitution in Drosophila conserved noncoding blocks. Frequencies of observations are in parentheses below total observed counts. Reciprocal substitutions were pooled (i.e.,mel A:vir T+mel T:vir A = A↔T) because our divergence data is pairwise, and therefore the polarity of the change is ambiguous. Bold arrows indicate transition substitutions.
