Question

which type of selection leads to increased phenotypic and genetic variation?
directional
selection
stabilizing
selection
disruptive
selection
species selection

Explanation:

To determine which selection increases phenotypic and genetic variation, we analyze each option:

• Directional selection: Shifts the population toward one extreme phenotype, reducing variation for that trait.
• Stabilizing selection: Favors intermediate phenotypes, reducing variation by eliminating extremes.
• Disruptive selection: Favors extreme phenotypes over intermediates. This splits the population into groups with different traits, increasing both phenotypic (visible traits) and genetic (allele frequencies) variation as more extreme alleles are favored.
• Species selection: Acts on entire species (e.g., speciation rates), not directly on phenotypic/genetic variation within a population.

Thus, disruptive selection increases variation.

Answer:

disruptive selection