Bistability and Switching Behavior in Moving Animal Groups

Moving animal groups such as schools of fish and flocks birds frequently switch between different group structures. Standard models collective motion have been used successfully to explain how stable form via local interactions individuals, but they are typically unable produce that exhibit spontaneous switching. We only aware one model, constructed for barred flagtail known rely on alignment attraction organize their motion, has shown generate this type behavior in 2D (or 3D). Interestingly, another species fish, golden shiners, do switching use repulsion, not alignment, coordinate themselves schools. Suggesting may be explained by repulsion alone, without an interaction. Here we introduce a model based show exhibiting similar observed experiments with shiners emerges. also establish occur two boundary-free extensions the model. Our work suggests bistability other moving attractive repulsive alone.