Figure 4. Sequencing of cax7 revealed a small region of high differentiation between soil types: 200 bp sliding windows of FST are shown in black.

Serpentine populations have much less polymorphism in this region that granitic populations (200 bp sliding windows of heterozygosity are shown in blue for serpentine, red for granite). Vertical lines delineate a region of 70 bp where 8 of 23 amino acids are polymorphic in granitic populations and fixed in serpentine populations.