Braess's paradox in tandem-running ants: When shortest path is not the quickest
Biological Physics
2026-04-01 v1 Adaptation and Self-Organizing Systems
Populations and Evolution
Abstract
Braess's paradox -- where adding network capacity increases travel time -- is typically attributed to selfish agents. Although eusocial colonies maximize collective fitness, we find experimentally that \emph{Diacamma indicum} ants exhibit this paradox: Leaders favour the shortest path even when it slows the colony. We present a quantitative model of the exploration-exploitation trade-off, demonstrating that evolutionary forces selecting for shortest-path identification can force suboptimal global states. This proves the paradox can emerge in highly cooperative systems without individual selfishness.
Keywords
Cite
@article{arxiv.2603.26226,
title = {Braess's paradox in tandem-running ants: When shortest path is not the quickest},
author = {Joy Das Bairagya and Udipta Chakraborti and Sumana Annagiri and Sagar Chakraborty},
journal= {arXiv preprint arXiv:2603.26226},
year = {2026}
}