The process of natural selection brings out the most helpful variation of traits in a population by–

the selective breeding of individuals with the most desirable traits to produce offspring with the best combination of traits.

changing the traits of individuals over time until each becomes better adapted to its native habitat.

mutating the DNA of offspring to produce more beneficial traits in each generation.

eliminating the less beneficial traits through the death of individuals with less fit traits before they pass on those traits to offspring.

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eliminating the less beneficial traits through the death of individuals with less fit traits before they pass on those traits to offspring.