How sharpshooter insects exploit biological superpropulsion to catapult their droplet pee

Sharpshooter insects feed on plants' xylem fluid using their pierce-sucking mouthparts. Due to the low-nutrient content of this ingested fluid, these insects suck up to 300 times their natural body weight per day in order to obtain adequate nutrients. Interestingly, these insects resort to an exquisite mechanism to discharge their fluidic waste: they catapult their droplet pee one at a time using a resilin-actuated anal stylus at high speeds and accelerations. In this talk, we show that by tuning the kinematics of their stylus to the physical properties of the droplet, these insects fling the droplets at higher speeds than their stylus in a phenomenon dubbed as superpropulsion. Using a mathematical framework, we showcase the limits of superpropulsion in biological settings and we seek to disrupt this finely tuned mechanism by snipping their hydrophobic hairs. We also demonstrate how this mode of propulsion is energetically favorable compared to other mechanisms of waste disposal such as jetting at the length scale of these insects.