Supplementary Table E.1

Characterisation of loci by MCHEZA, BayeScan and Samβada. For each locus, estimates of F_ST and associated significance values obtained using MCHEZA and BayeScan are given. Outlier loci found by Samβada are documented together with the environmental variable(s) showing significant correlations with the presence of the dominant allele ordered according to descending Wald scores. Additionally, the allele frequency differentials (δ) along with estimates of the genomic clines analysis as calculated by Introgress are shown. ‘Genomic cline’ indicates whether a locus shows a significant excess (H+) or deficit (H-) of S. hercynicus genotypes in a S. ovatus background. Fisher’s exact test statistics (χ², P_adj) are given, indicating whether a locus was found as being taxon-specific (H - S. hercynicus; O - S. ovatus). P-values (P_adj) were adjusted according to Benjamini and Hochberg (1995) to account for multiple testing. The last column gives the Sperman's rank correlation coefficient and P-value for the correlations tested between environmental variables detected by Samβada and frequencies of the present allele (band presence). dark red - loci that were found as being under divergent selection, that showed a significant relationship with an environmental variable, that showed significant deviation from a model of neutral introgression and that were found as being taxon-specific; light red - loci with allele frequency differentials δ > 0.250