Weegy: Geographic isolation occurs when members of a population are physically seperated due to a change in habitat (as in a new river enters a habitat and seperates the population in two). [ Once the populations is seperated the population on one side has absolutely no contact with the other side. Therefore mating between the two halves of the population ceases, and speciation occurs when the two populations have lived apart long enough that they can no longer produce viable offspring because of gene mutation
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