Investigating Schooling Behavior with Statistical Mechanics*

Collective behavior is ubiquitous in living systems. While there are several current models that successfully describe qualitative features of collective structures in animal behavior, the dynamical behavior of these systems in response to perturbation is not well understood. We examine the response of laboratory schools of negatively phototaxic freshwater fish to a variety of projected light fields. We observed laboratory schooling events of rummy nose tetra (Hemigrammus bleheri) in a shallow tank using a high-speed camera and particle-tracking setup. We employed both static light fields and dynamic light fields which were used to apply a normal stress on the school increasing the density of the system with time. Our results highlight how a materials and thermodynamic approach can give insights to current models.