The Development of Collective Structure and its Response to Environmental Change

Norman L. Johnson

Theoretical Division

Los Alamos National Laboratory

MB B216, Los Alamos, New Mexico USA


How do collective processes in decentralized, self-organizing systems respond to environmental change? What are the contrasting roles of collective structures and innovative components (variation, diversity, entropy), and how do these roles change with different rates of environmental change? To answer these questions, a simple self-organizing system is examined a simulation of foraging for food by ants in the presence of environmental change. This model system has been argued to be similar in dynamics to decentralized components of many collective systems - ecologies, economies, knowledge systems, societies, political systems, etc. The simulations are first shown to illustrate a developmental view of evolving systems, captured by the developmental stages of Formative, Co-Operational and Condensed. The effects of different rates of environmental change are then presented. For small rates of change, the system productivity is largely unchanged. As the rate increases, innovative information becomes more important to sustaining the productivity. As the rate further increases, episodic failure is observed as stabilizing collective structures fail, and the system regresses to earlier developmental stages. The collective structures are shown to inhibit the performance of the system as a whole in rapidly changing environments. A quantitative measure is developed that captures the efficacy of the collective structure. A variation of the system with a mechanism for sustaining collective structures is found to be more sensitive to environmental change, duplicating the decline in productivity observed in aging systems.

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