Diffusion plays an unusual role in ecological quasi-neutral competition in metapopulations

We investigate the phenomenology emerging from a two-species dynamics under the scenario of a quasi-neutral competition within a metapopulation framework. We employ stochastic and deterministic approaches, namely spatially constrained individual-based Monte Carlo simulations and coupled mean-field ODEs. Our results show that the multifold interplay between competition, birth–death dynamics and spatial constraints induces a nonmonotonic relation between the ecological majority–minority switching and the diffusion between patches. This means that diffusion can set off birth–death ratios and enhance the preservation of a species.