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A metapopulation is a group of populations that are separated by space but consist of the same species. These spatially separated populations interact as individual members move from one population to another.etapopulation Theory. Metapopulation theory states that a large population consisting of a single species is most stable over a large area when it is divided up into smaller subpopulations. These subpopulations take advantage of small, local environments, like your backyard or the park down the street.
Overpopulation occurs when a population of a species exceeds the carrying capacity of its ecological niche. Overpopulation is a function of the number of individuals compared to the relevant resources, such as the water and essential nutrients they need to survive.It can result from an increase in births, a decline in mortality rates, an increase in immigration, or an unsustainable biome and depletion of resources.n 2013 the human population was 7 billion. By 2025 the world population is expected to grow by an additional 1 billion. Depending on which estimate of overpopulation is used, human overpopulation may or may not have already occurred.