Figure 7.

Water condensation on epoxy replicas of structured surfaces. The epoxy replicas were cut into disks with a diameter of 15 mm. These disks were thermally equilibrated to 20.5 °C and then held for 15 s in water-saturated air at a temperature of 80 °C. The amount of water was determined by the mass difference of each replica. Clearly structured surfaces allow for more condensation when compared with unstructured ones. Even an unspecific roughness introduced by polishing paper (roughness, R_a ≈ 3 µm) increased the amount of water, although not significantly (p = 0.070). The replica of a non-moisture harvesting lizard Scincus scincus exhibits no significant increase of the condensation (p = 0.093). The replicas of the moisture harvesting lizards Moloch horridus (p = 0.032), Phrynocephalus arabicus (p = 0.034) and especially Phrynosoma cornutum (p = 0.007) show a significantly increased water condensation. Significance was tested by use of a two sided t-test assuming different standard deviations for the samples.