In this model, based on an inkjet printer and enlarged models of spores, a high-speed camera shows how spores use the physics of merging droplets to uniformly launch themselves out into the world
(Image by Chuan-Hua Chen, Duke University)
Fungal spores spread by hitching a ride on other animals or travelling on their own. In one of the methods, the spore is picked up by a water droplet, which is then propelled upwards. Exactly how this is done has been a mystery to scientists – until now. A new paper describes how two different-sized water droplets work in tandem to launch the spore into the air and away from its tether. The ephemeral nature of the event proved to be an obstacle in the past: while it takes minutes for the droplet to accumulate enough water the necessary size for takeoff, the actual launch takes place in milliseconds. Researchers used an inkjet printer and high-speed cameras to solve this mystery. The actual mechanism behind the mysterious takeoff is fascinating: When the fatal drop joins the drop that’s spread on top of the spore, the drops lose surface area and release surface energy, providing the momentum for the launch.
Authors:
Fangjie Liu, Roger L. Chavez, S. N. Patek, Anne Pringle, James J. Feng, Chuan-Hua Chen
Corresponding author:
Chuan-Hua Chen, Mechanical Engineering and Materials Science, Duke University, Durham, NC, US, Email: chuanhua.chen@duke.edu
Canadian author:
James J. Feng, Chemical and Biological Engineering, Mathematics, University of British Columbia, BC, Email: james.feng@ubc.ca
Original paper published in the Journal of the Royal Society Interface on July 25, 2017.
