Which process leads to changes in allele frequency through non-random mating?

The process that leads to changes in allele frequency through non-random mating is sexual selection. Sexual selection is a form of natural selection where individuals with certain inherited characteristics are more likely than others to obtain mates. This selective mating can result in an increased frequency of alleles associated with preferred traits.

For example, in many species, females may choose mates based on certain desirable traits such as bold coloration, elaborate courtship displays, or strength. This preference can significantly influence the allele frequencies within the population, as those traits become more common when they are favored during mate selection. Over time, this can lead to pronounced differences between males and females (sexual dimorphism) and can even drive speciation in some cases.

In contrast, natural selection refers to the differential survival and reproduction of organisms due to variations in phenotype, which is not restricted to mating choices. Genetic drift involves random changes in allele frequencies, especially in small populations, that occur by chance rather than by selection. Gene flow is the transfer of alleles or genes from one population to another, which can alter allele frequencies but does not inherently involve mating choices. By focusing on mate selection criteria, sexual selection directly impacts genetic variation and allele frequency through non-random mating preferences.