Coevolution and Symbiosis in Metapopulation Models

Abstract

Symbiosis in the natural world is of great evolutionary significance. The concept of symbiosis has been applied for designing evolutionary algorithms. In this paper, symbiosis is considered an operator instead of a state, and symbiotic association is regarded as a result of the emergent cost-benefit properties during an evolutionary process. A coevolutionary individual-based metapopulation model of an endosymbiont-host system is introduced in which two species, the potential host and parasite, are assumed. All the subpopulations in the model are represented by NKC models. A random-parasitism model is applied for representing symbiotic associations between a parasite and a host with no predefined intrinsic cost-benefit property. The symbiostic associations between hosts and parasites are considered genetic relationship through which genome of the parasite is transferred to the host. We investigated the coevolutionary dynamics through computer simulations and found the qualitative conditions where symbiosis stably emerges in the model.