Differentiation and Selection
We used Popoolation2 (Kofler et al., 2011) to evaluate nucleotide diversity (π), differentiation (FST ) and Tajima’sD between northern and southern pool-seq datasets.FST values were calculated using a non-overlapping sliding window approach (min-count -2, min-coverage 4, max-coverage 70, min-covered-fraction 0.2, pool-size 30, window-size 10 000, step-size 10 000). Tajima’s D values were calculated with Npstat v1 (Ferretti et al., 2013) using a sliding window approach (window_length 10 000).