title: Ant groups optimally amplify the effect of transiently informed individuals.
abstract: To cooperatively transport a large load, it is important that carriers conform in their efforts and align their forces. A downside of behavioural conformism is that it may decrease the group's responsiveness to external information. Combining experiment and theory, we show how ants optimize collective transport. On the single-ant scale, optimization stems from decision rules that balance individuality and compliance. Macroscopically, these rules poise the system at the transition between random walk and ballistic motion where the collective response to the steering of a single informed ant is maximized. We relate this peak in response to the divergence of susceptibility at a phase transition. Our theoretical models predict that the ant-load system can be transitioned through the critical point of this mesoscopic system by varying its size; we present experiments supporting these predictions. Our findings show that efficient group-level processes can arise from transient amplification of individual-based knowledge.
authors.affiliation: Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot 7610001, Israel.
authors.forename: Aviram
authors.initials: A
authors.lastname: Gelblum
authors.affiliation: Department of Chemical Physics, Weizmann Institute of Science, Rehovot 7610001, Israel.
authors.forename: Itai
authors.initials: I
authors.lastname: Pinkoviezky
authors.affiliation: Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot 7610001, Israel.
authors.forename: Ehud
authors.initials: E
authors.lastname: Fonio
authors.affiliation: Department of Chemical Physics, Weizmann Institute of Science, Rehovot 7610001, Israel.
authors.forename: Abhijit
authors.initials: A
authors.lastname: Ghosh
authors.affiliation: Department of Chemical Physics, Weizmann Institute of Science, Rehovot 7610001, Israel.
authors.forename: Nir
authors.initials: N
authors.lastname: Gov
authors.affiliation: Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot 7610001, Israel.
authors.forename: Ofer
authors.initials: O
authors.lastname: Feinerman
mesh_terms: D000818:Animals; D001000:Ants; D001522:Behavior, Animal; D003299:Cooperative Behavior; D006126:Group Processes; D012919:Social Behavior