Question

Which type of selection tends to increase genetic variation? A. Disruptive selection B. Directional selection C. Stabilizing selection

Answer 1

Answer:

Which type of selection tends to increase genetic variation? A. Disruptive selection B. Directional selection C. Stabilizing selection

The Answer is option A (Disruptive selection)

Explanation:

Selection can either shift the mean value of a trait, reduce the trait's variation, or increase its variation.

Genetic variation which allows natural selection to increase or decrease frequency of alleles already in the population is a source of phenotypic variation as it refers to differences in all the hereditary information of members of the same species.

Disruptive Selection is important in maintaining variation and initiating speciation as it Increases Variation by favoring alleles corresponding to more extreme phenotypes. But for it to occur, the mean phenotype has to experience the lowest fitness. Disruptive selection affects the frequency distributions of alleles and genotypes within a population.

Disruptive selection is based on the variance of a trait in a population as it increases genetic variance by equalizing the frequencies of existing alleles at polymorphic loci (a genetic loci with two or more alleles). Disruptive selection maintains and may even increase variation in natural populations by favoring extreme phenotypes, individuals with extreme values for a trait have greater reproductive success than individuals with intermediate values.