Fig. 1.

Plant material. a Location of the 163 A. thaliana populations across the Midi-Pyrénées region (southwest of France). The average distance among populations was 99.9 km (median = 92.6 km, SD = 55.4 km). Blue dots represent the 80 populations collected in both autumn and spring, red dots represent the 79 populations collected in spring only and orange dots represent the 4 populations collected in autumn only. The map clearly shows that the range of sampling across the Midi-Pyrénées region was homogeneous during the two sampling seasons. b Diversity of habitats encountered by A. thaliana in the Midi-Pyrénées region