Meeting Abstract
Splash cup plants disperse their seeds by exploiting the kinetic energy of raindrops. The splash cup of the plant is a 3-5 mm vessel that holds seeds. When raindrops impact the splash cup, seeds are projected up to 1 m away from the parent plant. This study focused on the conical splash cups of the genera Chrysosplenium (golden-saxifrage) and Mazus. A systematic experimental study conducted by Amador et al. (2013) found a 40° cone angle maximized dispersal distance when seeds were not present. Our study used a 40° cone angle with the addition of seeds of varying characteristics. We 3D-printed the conical fruit bodies of the splash cups using UV curable resin and then used high-speed video to find splash characteristics such as angle and velocity of seeds and splashing drops as they exited the seed cup. Dispersal distance was calculated by measuring the distance from the model to the final resting position of the seeds and droplets. Splash characteristics and dispersal distances of seeds with differing characteristics such as size, shape, texture, density, and hydrophobicity were compared to one another, as well as to the case of having no seeds present. Our data showed that the presence of seeds dramatically decreased dispersal distance and altered splash characteristics. In addition, our data showed that seeds with different characteristics yielded splashes with differing dispersal distance and splash characteristics.
