Figure 3. Functional degradation of 2^m.

(A) Using two different outgroups (diamond = golden-crowned sparrow, circle = Harris’ sparrow), the direction of selection statistic is strongly negative on 2^m, indicating an increased level of non-sysnonymous polymorphism. (B) For genes within the inversion, gene expression in higher for tan birds than heterozygous (2/2^m) white-morph birds and (C) in white birds, the white (2^m) allele tends to be under-expressed relative to the tan (2) allele (**: p < 0.01; ***: p < 0.001). Error bars represent 95% confidence intervals (standard error). See also Figure S2, S4, and Table S1.