Study of physical, biological, and chemical aspects of vortex forming animal swarms in theory and experiment, especially in Daphnia

• Applicant: Dr. Anke Ordemann
• Subject Area: Statistical Physics, Nonlinear Dynamics, Complex Systems, Soft and Fluid Matter, Biological Physics
• Term: Funded in 2005
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5452057

The proposed interdisciplinary project deals with the physical, biological, and chemical aspects of vortex forming swarms of self-propelled agents in theory and experiment.The biological agent employed for the experimental part of the study is the common fresh-water zooplankton Daphnia. The project consists of two research directions to be followed in parallel:(1) The investigation of the transition from gathering to collective vortex motion in self-propelled agent swarms and the preconditions necessary for this transition to occur. This is proposed to be studied by means of (a) computer modeling, especially with respect to the analysis of the interactions between the agents and the surrounding medium, as well as inter-agent interactions, and (b) experiments which allow tracking of the path of individual Daphnia and the water movement in high density swarms.(2) The detailed experimental investigation of the behavior of individual animals to changes in their environment, i.e. changes in kairomone (chemical cues from predators) and food concentration, changes in light conditions, or changes in animal density.This is proposed to be analyzed mainly by electrorecording neural responses of Daphnia and characterizing their swimming behavior. Besides its own right, results of this study are important for the development of follow-up experiments dealing with the transition from swarming to collective vortex motion and the optimization of existing computer models, as outlined above in (1).

• DFG Programme: Research Grants