Fig. 5. A phylogeny using only DNA data from the 1.2-kbp-long Alba candidate locus from Alba individuals in our species dataset, including additional samples from C. philodice (from Maryland, USA) and the previous GWAS study of C. crocea (from Cataluña, Spain).

Branch color corresponds to geographic region (blue = North America, orange = Holarctic, and green = Eurasia and Northern Africa), and branch length corresponds to substitution differences. Sample clustering suggests that alleles are shared between C. eurytheme from California and C. philodice originating from Maryland (philodice names ending in MD). Also, note the distinct variation among alleles in both these species (there is branching within this clade). This sharing of allelic variation between species from opposite sides of North America is consistent with both the long-term maintenance and introgression of Alba alleles. Similar evidence of allele sharing and diversity among Alba alleles is seen within C. crocea samples, which includes an allele from C. erate. Nodes with support > 90% indicated by white circle and the support value upon that branch.