If a mutation results in an organism with new characteristics then eventually a new species will be formed if more such mutations will continue to accumulate in the individual. Mutations result into the accumulation of variations in an individual and when such variations keep on accumulating in a particular organism consistently it leads to formation of a new species or we can say that evolution has occured.
A mutation is a random change in DNA which therefore affects a gene and/or chromosome. Most mutations have no effect on the phenotype. Some influence phenotype to some extent. Very few create a new phenotype. Mutations can be inherited and therefore passed on from one individual to another. If a mutation causes a new phenotype that makes an organisms better suited to a particular environment, it can lead to rapid change in the characteristics of the individuals in that species.
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