Tiny Features Keep Termite Wings Dry

Proving yet again that nature is a skilled nanotechnologist, scientists in Australia have discovered that termites keep their wings free of water using micro- and nanostructures on the wings’ surface (ACS Nano, DOI: 10.1021/nn900869b). Compared with other insects, termites have a large wing surface area in relation to their body mass. They’re also weak flyers and often take flight in the rain. All these things make them susceptible to becoming waterlogged. Gregory S. Watson and Jolanta A. Watson of James Cook University along with Bronwen W. Cribb of the University of Queensland therefore reasoned termite wings must have a water-repelling mechanism. Taking an extreme close-up of both Nasutitermes and Microcerotermes wings, the researchers noted star-shaped microstructures and tiny hairs with nanoscale ridges along the shaft. These ridges, they discovered, are critical. When the team coated a hair with enough hydrophobic polydimethylsiloxane to make the hair smooth, it lost its water-repelling power. “Understanding the interaction of water with surfaces through development of the scientific basis for these processes will ultimately lead to the next generation of advanced materials with attributes such as contamination resistance, self-cleaning, and for water collection and conservation,” the researchers write.