Fig. 6.

—Genetic structure and relationships among lakes and species. (A) Discriminant analysis of principal components (dAPC) of the different lakes (Cliff, Indian, Webster, East, Témiscouata) for either Dwarf or Normal whitefish (D or N), representing 3D relationships among populations. The first axis (LD1, 39.5%) captures the geographical signal of differentiation among lakes. The third dAPC axis (LD3, 16%) separates species pairs according to their residual genetic promixity to ancient glacial lineages represented by the least introgressed populations from Cliff Lake. Positive coordinates represent populations with high proportions of Atlantic ancestry whereas negative coordinates reflect increased proportions of Acadian ancestry. The fourth axis (LD4, 11%) tends to separate species pairs within each lake. The second dAPC axis LD2 is not shown here to avoid partial redundancy with LD1, but is provided as a Supplementary Material online. (B) Boxplot of individual coordinates along the fourth dAPC axis (LD4), highlighting the divergence parallelism between species among lakes.