How does natural variation affect evolution?
Put simply, the variations that survive best in a population are the parents of the next generation, passing along their genetic characteristics and no other. . And it is not just affecting evolution, it is part of the basic definition, which is essential: 1) Mutations occur in a population for a variety of reasons, and can be passed down to future generations. 2) Those mutations that improve the survival rate of the individual will form a larger part in the breeding population and become more common, while those that reduce the survival rate of the individual form a smaller part of the breeding population, and tend to die out.
Natural variation is the raw material from which evolution takes shape. Whether due to mutations or (at a higher rate) sexual recombination, natural variation — the diversity among individuals within an interbreeding population — produces ‘outliers’ of phenotype (mutant is such a harsh word 🙂 Then environmental factors direct natural selection, and eventually speciation, to move in that direction.
