Superhydrophobic diving flies (

Superhydrophobic surfaces have been of key academic and commercial interest since the discovery of the so-called lotus effect in 1977. The effect of different ions on complex superhydrophobic biological systems, however, has received little attention. By bringing together ecology, biomechanics, physics, and chemistry our study provides insight into the ion-specific effects of wetting in the presence of sodium carbonate and its large-scale consequences. By comparing the surface structure and chemistry of the alkali fly—an important food source for migrating birds—to other species we show that their uniquely hydrophobic properties arise from very small physical and chemical changes, thereby connecting picoscale physics with globally important ecological impacts.