Zooplankton have developed propulsion mechanisms and swimming modes that minimise the fluid disturbance that they generate. New study from Centre for Ocean Life has discovered these propulsion modes that help zooplanton to hide from their predators.
Plankton compromise their survival when they swim and feed because the fluid disturbances that they generate may be perceived by predators. To what extent can zooplankton minimize the fluid signal, and what is the adaptive significance of the large diversity in propulsion modes found among zooplankton? This study examines propulsion in a large range of zooplankton, from micron sized flagellates to large copepods, and demonstrates that when swimming and feeding are integrated processes, the generated fluid disturbance extends much further in the water than is the case for zooplankton that swim only to relocate. Quiet swimming is achieved through ‘breast stroke swimming’ or by swimming-by-jumping, while other propulsion modes are much noisier. This pattern applies across species, suggesting that the quiet propulsion modes have evolved multiple times.
The paper can be found here
Reference
Kiørboe, Jiang, Gonçalves, Nielsen & Wadhwa (2014) Flow disturbances generated by feeding and swimming zooplankton. PNAS. www.pnas.org/cgi/doi/10.1073/pnas.1405260111