Coevolution of competing systems: local cooperation and global inhibition

TL;DR

This paper models the coevolution of competing systems with intra-system cooperation and inter-system aggression, revealing how resource supply influences stability, aggression benefits, and system robustness through mean field and discrete models.

Contribution

It introduces a combined mean field and discrete modeling approach to analyze how cooperation and aggression coevolve in heterogeneous systems under resource constraints.

Findings

Stable inhomogeneous solutions exist even for identical systems.

Large perturbations are needed for aggressive systems to change regimes.

Less-organized systems benefit more from aggression, while mixed systems are more robust.

Abstract

Using a set of heterogeneous competing systems with intra-system cooperation and inter-system aggression, we show how the coevolution of the system parameters (degree of organization and conditions for aggression) depends on the rate of supply of resources. The model consists of a number of units grouped into systems that compete for the resource; within each system several units can be aggregated into cooperative arrangements whose size is a measure of the degree of organization in the system. Aggression takes place when the systems release inhibitors that impair the performance of other systems. Using a mean field approximation we show that i) even in the case of identical systems there are stable inhomogeneous solutions, ii) a system steadily producing inhibitors needs large perturbations to leave this regime, and iii) aggression may give comparative advantages. A discrete model is used in order to examine how the particular configuration of the units within a system determines its performance in the presence of aggression. We find that full-scale, one sided aggression is only profitable for less-organized systems, and that systems with a mixture of degrees of organization exhibit robustness against aggression. By using a genetic algorithm we find that, in terms of the full-occupation resource supply rate, the coevolution of the set of systems displays a variety of regimes. This kind of model can be useful to analyse the interplay of the cooperation/competition processes that can be found in some social, economic, ecological and biochemical systems; as an illustration we refer to the competition between drug-selling gangs.