Figure 2.

Distributional ranges of Primula elatior (blue), Primula vulgaris (yellow), and their overlap (green) in Europe. Distributional maps were generated from data compiled from Global Biodiversity Information Facility (GBIF: http://data.gbif.org/), Info Flora (www.infoflora.ch), Flora Web Deutschland (http://www.floraweb.de), Flora Europaea (Valentine and Kress 1972), Flora of the USSR (Komarov 1963), and Richards (2003, personal communication). Highlighted in red is Switzerland, where occurrences records of both species were used to estimate ecogeographic barriers (RI_ecogeo) and the experimental part of our study was conducted (see text).