Results of linear models testing the effect of tree branch length to the root extracted from a <i>F</i>_ST-based population phylogeny on different metrics of selection efficacy.

A: relationship between ωNA and tree branch length; B: relationship between ωA and tree branch length; C: relationship between α and tree branch length. See text for a definition of each metrics. Sample sites are coloured by region. The blue line represents the value of the regression line. In all panels each point represents a sampling site and is coloured according to the region in which it was sampled. Displayed is the adjusted R2 along with its p-value. (TIF)