Figure 6. Sexually-concordant effects of fibrosis on reproductive fitness result in alignment of multivariate selection across the sexes in Roselle lake, particularly selection on multivariate shape.

Histograms represent the empirically constructed sampling distributions of the vector correlation between male and female multivariate selection gradients estimated in separate linear models, when gradients are estimated using morphological traits alone (red) or including fibrosis (blue). Panel A shows this contrast in an analysis using the first three morphological principle components (i.e., size and two dimensions of shape that in total capture 85% of the phenotypic variation). Panel B shows the contrast in an analysis using PC2 and PC3, showing sexually-antagonistic selection on shape traits alone. Panel C shows the contrast when all raw morphological traits are modelled. Dashed lines represent the correlation estimated from the original REML estimates. Histograms are correlations calculated from gradient vectors obtained from resampling (100,000x) from a multivariate normal distribution centered on the original estimates and covariance from the estimated covariance matrices of the fixed effects.