Meeting Abstract
Water striders are abundant in areas with high humidity and rainfall. Raindrops can weigh 20 times the insect and some pelagic species spend their entire lives at sea. In this combined experimental and theoretical study, we use high-speed videography to film raindrop collisions on water striders and dynamically scaled mimics. Raindrops force the insect subsurface upon direct impact. As the ensuing cavity collapses, the strider is shot into the air alongside a Worthington jet. We show the insect’s rigid exoskeleton, low density, resistance to wetting when briefly submerged and its ability to regain an equilibrium rest state, render it impervious to impacting droplets. In the event of cuticle wetting, raindrops become dangerous and submersion makes the water strider incapable of penetrating the air-water interface from below, which appears impossible without the aid of a plastron. Indirect impacts elicit jumps as the strider maneuvers surface perturbations. Our findings show water striders are robust to adverse environmental conditions and augurs well for the development of biomimetic robots.
