Figure 4.

Patterns of regional connectivity and migration directionality in RAD data. Historical signatures of expansion between the major clades recovered in our iqtree analysis using RAD loci. We follow the nested structure of the phylogeographic tree, first testing directionality between the northern and southern groups, and then between major divisions within the groups. Our analysis shows expansion from south to north (thick arrows). Within the two major groups, expansion from the Mojave populations to the South Transverse populations, and from Pinnacles toward Panoche.