Fig. 2

Principal component analysis (PCA) for each resistance mutation. For each resistance mutation a vgsc “kdr” L1014F, b ace-1 F290V, c ace-1 G119S and d) Ester²), the variables’ projections on the two first axes of the PCA are indicated by the arrows (for each axis, the explained variance percentage is indicated in brackets). The variables are the resistance allele frequency (fR) and the percentages of natural (Nat), urban (Urb) and agricultural (Agri) areas in a 2.5-km radius area around each sampling site