Microsatellite-based clustering analyses. Top panel: UPGMA tree inferred from multilocus microsatellite-derived pairwise F_STvalues. Brackets indicate possible genetic clustering of 3 groups based on cutoff of F_ST= 0.05. Genetic distance between Cluster 1 and Cluster 2, F_ST= 0.060; between Cluster 2 and Cluster 3, F_ST= 0.098; between Cluster 1 and Cluster 3, F_ST= 0.092. Bottom panel: Plot from microsatellite-based structure analysis at K= 3. Each individual is represented by a vertical bar displaying membership coefficients to each of 3 clusters, depicted as white, gray, and black. Individuals are grouped by collection site.