Initiation and spread of escape waves within animal groups

DOI Web Site Web Site 1 Citations
  • James E. Herbert-Read
    Department of Mathematics, Uppsala University, Uppsala 75106, Sweden
  • Camille Buhl
    School of Biological Sciences, The University of Sydney, Sydney, New South Wales 2006, Australia
  • Feng Hu
    College of Physics and Electronic Engineering, Chongqing Normal University, Chongqing City 400047, China
  • Ashley J. W. Ward
    School of Biological Sciences, The University of Sydney, Sydney, New South Wales 2006, Australia
  • David J. T. Sumpter
    Department of Mathematics, Uppsala University, Uppsala 75106, Sweden

Description

<jats:p>The exceptional reactivity of animal collectives to predatory attacks is thought to be owing to rapid, but local, transfer of information between group members. These groups turn together in unison and produce escape waves. However, it is not clear how escape waves are created from local interactions, nor is it understood how these patterns are shaped by natural selection. By startling schools of fish with a simulated attack in an experimental arena, we demonstrate that changes in the direction and speed by a small percentage of individuals that detect the danger initiate an escape wave. This escape wave consists of a densely packed band of individuals that causes other school members to change direction. In the majority of cases, this wave passes through the entire group. We use a simulation model to demonstrate that this mechanism can, through local interactions alone, produce arbitrarily large escape waves. In the model, when we set the group density to that seen in real fish schools, we find that the risk to the members at the edge of the group is roughly equal to the risk of those within the group. Our experiments and modelling results provide a plausible explanation for how escape waves propagate in nature without centralized control.</jats:p>

Journal

Citations (1)*help

See more

Report a problem

Back to top