Negative selection (natural selection)
（重定向自Purifying selection）
In natural selection, negative selection or purifying selection is the selective removal of alleles that are deleterious. This can result in stabilizing selection through the purging of deleterious variations that arise.
Purging of deleterious alleles can be achieved on the population genetics level, with as little as a single point mutation being the unit of selection. In such a case, carriers of the harmful point mutation have fewer offspring each generation, reducing the frequency of the mutation in the gene pool.