Numerical simulation of light-driven collective motion inspired by experimental observations

Area of Science:

• Collective behavior dynamics
• Biophysics
• Swarm intelligence

Background:

• External stimuli significantly influence collective motion in biological systems.
• Understanding fish school responses to dynamic cues is key for ecological and robotic applications.
• Previous experimental work at Université Paris Cité observed fish reacting to moving light.

Purpose of the Study:

• To develop a numerical model simulating fish school collective motion in response to a moving luminous stimulus.
• To replicate and analyze the dynamics observed in experimental studies.
• To investigate the mechanisms behind light-induced collective behavior transitions.

Main Methods:

• Agent-based modeling with particles exhibiting attraction to a light source and mutual repulsion.
• Incorporation of stochastic fluctuations influenced by light intensity.
• Simulation of dynamic illuminance changes over time.
• Analysis of particle polarization and average speed.

Main Results:

• The model successfully reproduced key experimental findings, including transitions from disordered to ordered motion.
• Simulations showed the formation of cohesive groups and high polarization under strong light.
• Analysis confirmed a light-induced phase transition in collective behavior.
• Results demonstrated strong agreement with experimental data.

Conclusions:

• The developed numerical model accurately captures collective fish behavior in response to dynamic luminous stimuli.
• Light intensity acts as a critical factor driving phase transitions in collective motion.
• The study provides valuable insights into the mechanisms governing how biological swarms respond to environmental cues.