Stochasticity may generate coherent motion in bird flocks.

Area of Science:

• Collective animal behavior
• Theoretical ecology
• Statistical physics

Background:

• Flocking and swarming are key examples of collective animal movement.
• Previous research focused on simple rules and correlations for coherent motion.
• Recent findings suggest flocking and swarming animals behave as if in elastic potential wells.

Purpose of the Study:

• To explain coherent motion in flocks using variations in noise intensity.
• To demonstrate how noise-induced potential well changes generate collective behavior.
• To link potential wells to flock characteristics like high-density borders and escape patterns.

Main Methods:

• Theoretical modeling of multiplicative noise effects on potential wells.
• Analysis of how noise variations alter attraction centers and correlations.
• Examination of emergent properties from noisy, confining potentials.

Main Results:

• Coherent motion arises from changing potential well shapes due to noise intensity variations.
• Scale-free correlations and high-density flock borders are explained by these potential wells.
• Collective escape patterns in starling flocks under predation are accounted for.
• Birds may inhabit unstable potential wells, while insects reside in stable ones.

Conclusions:

• Collective behavior in flocks and swarms can emerge from noisy potential wells.
• Noise-driven dynamics offer a unified explanation for flocking and swarming.
• Bird flocks may exist at criticality, influenced by individual perception.