Self-organized collective animal behavior — in swarms, flocks, schools, herds, or crowds — is ubiquitous throughout the animal kingdom. In part because it is so generic, it has engaged scientists from many disciplines, from biology to applied mathematics to engineering. But despite this broad interest, little empirical data exists for real animals; modelers have, therefore, been forced to settle for only qualitative large-scale information or to make ad hoc assumptions about the low-level inter-individual interactions, and the resulting models may not possess the robust qualities of natural animal groups. To address this dearth of data, we have conducted a laboratory study of swarms of the non-biting midge Chironomus riparius. Using multicamera stereoimaging and three-dimensional particle tracking, we measure the trajectories and kinematics of each individual insect in the swarm, and study their statistics and interactions. I will give an overview of our measurements, including the statistics of the swarm as a whole and the behavior of individual insects, and will discuss some of the implications of our results for modeling this complex system.
Nicholas Ouellette is an Associate Professor in the Department of Mechanical Engineering & Materials Science at Yale University. His research focuses on understanding the dynamics of nonlinear systems far from equilibrium, and has included projects on turbulent fluid flows, collective animal behavior, the erosion of granular materials, and active matter. He graduated from Swarthmore College in 2002 with majors in Physics and Computer Science, and earned his Ph.D. in Physics from Cornell University in 2006. Before coming to Yale, he did postdoctoral research at the Max Planck Institute for Dynamics and Self-Organization in 2006, and in the Physics Department at Haverford College from 2007-2008.