Figure 2.

A. The significance of background selection in a logistic regression model (which includes gene-specific mutation and selection variables) is plotted as a function of the index of panmixis and strength of selection against deleterious mutations. Background selection is significant at p < 0.01 across all but a small slice of parameter space corresponding to very low rates of outcrossing (black). The red lines bracket the region of parameter space over which background selection explains more of the local linkage probability than any other variable in the model. See Figure S4. B. Effects of background selection on levels of variation along the chromosomes under the best fitting background selection model.