Figure 7. Visual representation of the most likely model in the demographic history analysis conducted using ∂a∂i. According to the model, eastern and western monarchs diverged 112 thousand years ago with a migration rate of 7.33*10-7. The populations went through a pre-divergence bottleneck about 412 thousand years ago. The effective population size during the bottleneck was estimated to be nuB 13,284,249 and the joint effective population size of eastern and western monarchs was estimated to be 47,616,680.