Score scatter plot from PCA (PC axes 4 and 5) of m/z values (binned to 0.2 Da) obtained by metabolic fingerprinting of A. lyrata spp. petraea populations from Iceland, Sweden, Norway, Ireland, Scotland and Wales. Fingerprints were obtained from direct injection mass spectrometry of the aqueous phase (methanol : water) in negative ionization. All data were Pareto scaled prior to PCA (turquoise, Iceland (circles, Ice_1; squares, Ice_2; uptriangles, Ice_3; diamonds, Ice_4; asterisks, Ice_5; pluses, Ice_6; downtriangles, Ice_7; crosses, Ice_8); light green, Ireland (circles, Ire_2); red, Norway (circles, Nor_1; squares, Nor_2; uptriangles, Nor_3; diamonds, Nor_4; asterisks, Nor_5; pluses, Nor_6; downtriangles, Nor_7; crosses, Nor_8); dark blue, Scotland (circles, Sco_5; squares, Sco_7); orange, Sweden (circles, Swe_1; squares, Swe_2; uptriangles, Swe_3; diamonds, Swe_4; asterisks, Swe_5; pluses, Swe_6; downtriangles, Swe_7; crosses, Swe_8) dark green, Wales (circles, Wal_1)).