Dynamical network formation of C. elegans

Ordered collective motions are ubiquitous among locally interacting living beings. Experimental systems have been developed for non-living self-propelled particles, bacteria, and mammalian cells on a substrate, but there have been no experimental systems of multicellular organisms, which have much more complex behaviours, with various controllable parameters over a wide range.
Here, we have constructed an experimental system in which C. elegans collectively forms dynamical networks. We investigated the dependence of our designed experimental system on the substrate, ambient humidity and density of worms. Taking advantage of C. elegans genetics, we also controlled genetically determined motility by mutations. Furthermore, we developed an agent-based model with simple rules that reproduced the dynamical network formation and its dependences on the parameters, suggesting that the key behaviours for the network formation were alignment of worms after collision and smooth turning. This result revealed that the collective motion of the living things with advanced information processing systems can be described by a simple minimal model in a broad area of parameter space.