* Rare Events: Mutations are random changes in DNA sequence. They occur relatively infrequently.
* Single Copy: A new mutation initially appears in only one copy of the gene in a single individual.
* Large Population: In a large population, the chance of this single mutated copy being passed on to many offspring is statistically small.
Therefore, the frequency of a new allele is extremely low. It may take many generations for the allele to spread and increase its frequency in a population, if it does at all. Factors like natural selection, genetic drift, and migration can influence the fate of the new allele.
