Isolation-with-migration analysis of four species with significant structure across the 30°S biogeographic break.

<p>(a) Marginal posterior probability distribution of migration rate estimates in each direction for each species. (b) Estimated Θ (2 Ne) values for each biogeographic region (north and south) as well as the ancestral Θ against genetic differentiation (global Φ_ST). Asterisks denote estimated Θ 95% HPD that do not overlap with either ancestral Θ or the estimated Θ in the other biogeographic region. (c) Marginal posterior probability distributions of divergence time (<i>t</i>) estimates expressed in thousands of years (Kyr). Divergence time estimates were scaled using 2% and 10% per million year substitution rates. (d) Highest probability value of estimated migration rates (<i>m</i>) in each direction, and divergence times (<i>t</i>) expressed in thousands of years (Kyr) scaled using 2% per million year substitution rate, versus genetic differentiation (global Φ_ST). Asterisks indicate significant values based on the likelihood ratio test.