How ants move: individual and collective scaling properties

TL;DR

This study analyzes ant movement to understand individual and collective dynamics, revealing that activity duration is unrelated to speed, a Markov process explains speed profiles, and collective movement increases with ant numbers.

Contribution

Revisits ant movement laws, demonstrating that a Markov process explains speed profiles and that collective movement speed increases with group size.

Findings

No link between activity duration and speed.

A Markov process explains speed shape profile.

Movement speed increases with the number of ants.

Abstract

The motion of social insects is often used a paradigmatic example of complex adaptive dynamics arising from decentralized individual behavior. In this paper we revisit the topic of the ruling laws behind burst of activity in ants. The analysis, done over previously reported data, reconsider the causation arrows, proposed at individual level, not finding any link between the duration of the ants' activity and its moving speed. Secondly, synthetic trajectories created from steps of different ants, demonstrate that a Markov process can explain the previously reported speed shape profile. Finally we show that as more ants enter the nest, the faster they move, which implies a collective property. Overall these results provides a mechanistic explanation for the reported behavioral laws, and suggest a formal way to further study the collective properties in these scenarios.