Superhydrophobic properties are what allow plastrons to create an air bubble and thus allow respiration in such adapted insects and spiders. However, many species of insect or spider that live in close association with water evolve other types of hydrophobic surfaces beyond just plastrons or physical gills. Other spider surfaces of species that live in close association with the water have also been found to demonstrate increases in hydrophobicity and hair density. For example, Dolomedes is a semiaquatic spider, and has evolved to have the ability to move on water surfaces (Stratton et al 2004).

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Female Dolomedes orion from Okinawa (credit: Akio Tanikawa)

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Another example of an insect that uses a superhydrophobic surface for a purpose other than respiration is the Namib Desert beetle, which uses a superhydrophobic surface in order to harbor water, due to the fact that it lives in one of the driest places on earth. Its surface has patches of superhydrophibic and non-hydrophobic areas, giving it a bumpy texture and allowing it to collect water from fog for drinking (Parker and Lawrence 2001).

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Namib Desert beetle (Onymacris rugatipennis) in Dead Vlei, Namibia (credit: Thomas Schoch)

Many plant species have also evolved the use of superhydrophobic surfaces. For plants, such surfaces have the ability to keep the surface dry and protect from dust and pathogens because they are self-cleaning when rained on (Shirtcliffe et al 2006). Probably the most popular example of this is the Lotus flower, which has inspired numerous biomimetic attempts. Any water that collects on the lotus leaf collects and rolls off, taking any harmful materials with it (Marmur 2004).

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Indian Lotus Nelumbo nucifera in Kolkata, West Bengal, India. (Credit: J.M. Garg)