CBSE Class 10 Answered
Geographic isolation causes speciation because members of a population are unable to reproduce with one another. This reproductive isolation prevents mixing of the gene pool and allows each population to evolve along different paths according to the specific pressures present in the differing environments.
Members of a population may become geographically isolated due to changing climate or terrain. Once isolated from the main group, a population begins to adapt to the specific environment in which it is located. If the environments are diverse, a population that is geographically isolated from other members of the population may diverge into a separate species over time.
Basically, geographical isolation does not lead to the formation of new organisms within a species. In fact, it leads to the formation of a new species.