Discriminant Analyses of Principal Components (x-axis: PC 1, y-axis PC 2) of sculpin (Cottus spp., a) and brown trout (Salmo trutta, b). Lines between individuals and “group centers” show the genetic clusters. Larger/outer circles indicate the catchment and smaller/inner dots the population where the individual fish were sampled. Individual membership probabilities per cluster are shown in Fig. S4-1 and S4-2. For sculpin populations Bab and Stb additional asterisks show the mtDNA control region haplotypes. Haplotype HTCot01 was designated to C. gobio and HTCot07 to C. rhenanus (cp. Tab. S3-1).