Figure 1.

(a) Spatial location of the ponds (circles; size is proportional to area on a logarithmic scale) in Doñana National Park. (b–d) Schematic representation of a subset of ponds linked by different dispersal distances d of three hypothetical amphibian groups ((b) d=100 m; (c) d=500 m; and (d) d=1000 m). Black nodes and white nodes represent flooded and dry ponds, respectively. Solid lines indicate directed links between dry and flooded ponds. Broken lines represent undirected links between flooded ponds. Note that we can identify network components (i.e. groups of interlinked flooded ponds) at different scales.