Synchronized locomotion improves spatial accessibility in ant colonies and in oscillating active particles.

Synchronization is a common and important collective phenomenon in many biological, physical, and even social systems. Ant colonies from the genus Leptothorax exhibit a form of synchronized behavior where workers inside colonies’ nests become active together in rhythmic cycles that have a period of approximately 20 minutes. However, it is not currently known if these synchronized rhythms of locomotion confer any functional benefit to the collective behavior of colonies. By using a combination of multiple image analysis techniques, we show that inactive ants act as immobile obstacles to moving ants and that, compared with asynchronous movement, synchronized activity reduces the likelihood that active ants will encounter clusters of inactive ants that impede access to regions of the nest. We model this system as a set of confined, oscillating active particles where the level of particle phase synchrony, average activity level, and particle density can be directly manipulated. Our model simulations reveal that synchronous activity provides the greatest improvements to spatial accessibility when particle density is high and when the duration particles spend inactive is long.