Figure 2:

Decomposing genetic variance in a two-population system. The plot illustrates the expected distribution of genetic values in two populations under different selective pressures and the terms on the right list the total $\left(V_g\right)$ and between-population genetic variance $\left(V_{gb}\right)$ expected over the evolutionary process. For neutrally evolving traits (top row), we expect there to be an absolute difference in the mean genetic values $(|\stackrel{-}{g_A}-\stackrel{-}{g_B}|)$ that is proportional to $F_{ST}$. For traits under divergent selection (middle), $|\stackrel{-}{g_A}-\stackrel{-}{g_B}|$ is expected to be greater than that expected under genetic drift. For traits under stabilizing selection, $|\stackrel{-}{g_A}-\stackrel{-}{g_B}|$ will be less than that expected under genetic drift, and zero in the extreme case.