Figure 1

Power of the 41 microsatellites loci. a) Discrimination score (abscissa) for each of the 41 loci (ordinate). The discrimination score considered here is the area under the ROC curve which plots the sensitivity (ie probability to detect true positif) in function of the inverse of the specificity (probability to detect true negatif), after performing a logistic model explaining species status by allele composition. Scores of 0.5 indicate a monomorphic locus (a single, same allele in both species) or a polymorphic locus (the same several alleles in both species); scores of 1 indicate to a locus at which the two species studied do not share any allele. b) For the three Ardèche stations separately and together: q score (from Structure analysis) as a function of the h-index (from Introgress analysis) with 0 corresponding to C. nasus and 1 to P. toxostoma. In green, specimens with C. nasus mitochondrial DNA, in red specimens with a P. toxostoma mitochondrial DNA, in black mitochondrial DNA typing not available.