Viability of populations in a landscape

It has long been known that extinctions or wild oscillations in populations can occur when population density is too low, or when a population is confined to too small an area at high population density. This study discovers another cause of extinction. Cellular automata models of a single population in a landscape indicate that, if a population occupies an unconfined region smaller than a critical size, it can also become extinct in spite of healthy population density, the availability of suitable areas to migrate to, and the absence of competitors and predators.