Fig. 3: Estimated effective migration and geographic barriers.

A Estimated effective migration surfaces based on ddRAD-seq data. Sampling localities represented by black dots, sample sizes per locality proportional to size of dots. Note that black dots of deme locations in EEMS outputs are plotted on the map based on the number of demes assigned in the analysis, so several localities are collapsed into a single central dot and thus do not exactly match the real geographic locations. Blue areas represent genetic connectivity, orange areas represent genetic barriers. B Elevational profile of the study region showing main mountain ranges. The approximate courses of the major rivers in the region are overlaid as blue lines in both panels (Weser and Rhine). Population numbers follow Table 1.