Competition among Fugitive Species in a Harlequin Environment

We examine the qualitative behavior of differential equations for the proportion of insular patches of each of two kinds of habitat occupied by each of two species with characteristics rates of migration between patches and of local extinction within a habitat. Certain migration and extinction rates result in stable coexistence, even of closely similar species; others lead to competitive exclusion, even when each species is competitively superior in one kind of habitat. For a community of many species in many habitats, we surmise qualitative limits to the subdivision of resources, and alternative stable communities. Our results extend to species that live in successional or ephemeral habitats. We therefore conjecture equilibrial theories for the number of patches of habitat occupied by insular species, fugitive plants and invertebrates, or infesting parasites.