Natural selection is evolutionary change occurs through variation between individuals along with mutation, migration, and genetic drift. Natural selection is famous theory of Darwin which states that evolutionary change comes through the production of variation in each and every generation of species and differential survival of individuals with different combinations of these variable characters. Individuals with characteristics which increase their chance of survival will have more opportunities to reproduce and their offspring will also get benefit from the heritable, character. So over time these variants will spread through the population.
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