Meeting Abstract
Pond skaters (Gerridae) are a group of insects which permanently live on the surface of lentic waters. Each of their tarsi is equipped with dense arrays of hydrophobic hairs, which enable them to use surface tension to walk on water. Although these mechanisms have been studied in detail, it is still unclear how pond skaters maintain and clean their hydrophobic hairs. By measuring the shadows of the dimples generated by the pond skaters’ legs after contamination with hydrophilic microparticles (sodium aluminum silicate), we showed that the contact size of the pond skaters’ legs with the water surface decreased. Moreover, the bodies of contaminated pond skaters touched the water surface, which is not normally observed for uncontaminated individuals. The contact of the body with the water surface reduced the distance covered per rowing stroke. By contaminating pond skater legs with fluorescent particles, we showed that they possess self-cleaning properties, which come into play during each rowing stride cycle on the water surface and resemble the contact self-cleaning of adhesive footpads in geckos and insects. Even after multiple leg strides, we observed that contaminated pond skaters performed active grooming movements with specialized cleaning structures on their front and middle legs in order to clean the hairs on their tarsi. Further understanding of the underlying principles of insect cleaning might inspire the development of artificial devices for surface cleaning on the micro- or nanoscale.
