Anomalous fundamental diagrams in traffic on ant trails

TL;DR

This paper investigates traffic flow on ant trails using a stochastic cellular automaton model, revealing non-monotonic speed-density relationships and cluster formations, contrasting with human highway traffic.

Contribution

It introduces a novel model for ant trail traffic, demonstrating unique flow behaviors and effects of counterflow, expanding understanding of biological traffic systems.

Findings

Average ant speed varies non-monotonically with density.

Formation of loose clusters affects flow dynamics.

Counterflow influences trail traffic patterns.

Abstract

Many insects like ants communicate chemically via chemotaxis. This allows them to build large trail systems which in many respects are similar to human-build highway networks. Using a recently proposed stochastic cellular automaton model we discuss the basic properties of the traffic flow on existing trails. Surprisingly it is found that in certain regimes the average speed of the ants can vary non-monotonically with their density. This is in sharp contrast to highway traffic. The observations can be understood by the formation of loose clusters, i.e. space regions of enhanced, but not maximal, density. We also discuss the effect of counterflow on the trails.