Answer :
Geographical isolation (vicariance) is the main reason for the evolution of either side mouse into new species.
What is geographical isolation?
Two populations of the same species are geographically separated by a barrier, they will eventually become genetically distinct from one another. Even when they are exposed to the same kinds of environmental selection forces and are living in the same region, two populations of the same species can yet become genetically distinct from one another.
A new river cuts through a land mass, separating populations of mice on either side. these mice then evolve into new species on the two sides of the land mass, the separation of a group of organisms by a geographic barrier, resulting in the differentiation of the original group into new varieties or species.
Hence, vicariance is a kind of evolution caused by geographical isolation.
To learn more about the geographical isolation and vicariance the link is given below:
https://brainly.com/question/9601840?
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