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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.
A pseudocoelomate or blastocoelomate is any invertebrate animal with a three-layered body and a pseudocoel. The coelom was apparently lost or reduced as a result of mutations in certain types of genes that affected early development. Thus, pseudocoelomates evolved from coelomates. Pseudocoelomate is no longer considered a valid taxonomic group, since it is not monophyletic.