Researchers at University of Tsukuba have demonstrated, through multi-agent simulations in a two-dimensional space, that the combination of environmental variability and human migration may foster the evolution of human cooperative behavior because their joint effect disrupts non-cooperative groups while facilitating the emergence of cooperative groups.

Tsukuba, Japan—Cooperation is fundamental to human societies. Building on the hypothesis that heightened environmental variability in Africa during the Middle Stone Age influenced behavioral evolution, this study investigates the joint influence of environmental variability and human migration on the evolution of cooperation.

In their simulation model, the variability is represented as the random movement of resource-rich zones across a two-dimensional space, and the migration is represented by the resource-seeking migration of agents (e.g., humans). The agents interact cooperatively or competitively for resources and adopt their behavioral strategies by imitating neighbors with more resources.

The simulation results reveal that cooperation is more likely to evolve when environmental variability and mobility are sufficiently high. Moreover, the interactions between these factors hinders non-cooperative groups and encourages the formation of cooperative groups.

Unlike previous studies that examined environmental variability and migration separately, this study systematically analyzes their combined effects on the evolution of cooperation. Thus, it offers a novel perspective on how environmental dynamics and mobility may have shaped the evolution of human cooperation and, by extension, sociality.

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This work was supported by JSPS KAKENHI Grant Number JP23K20588 and by the Fujikura Foundation.

Original Paper

Title of original paper:

Evolution of cooperation among migrating resource-oriented agents under environmental variability

Journal:

Chaos, Solitons & Fractals

DOI:

10.1016/j.chaos.2025.117592

Correspondence

INABA Masaaki
Doctoral Program in Policy and Planning Sciences, Degree Programs in Systems and Information Engineering, Graduate School of Science and Technology, University of Tsukuba

Professor AKIYAMA Eizo
Institute of Systems and Information Engineering, University of Tsukuba

Related Link

Institute of Systems and Information Engineering