Question

Explain how speciation, directional, disruptive, and stabilizing selection affect biodiversity.

Answer 1

Speciation and the three selections (directional, disruptive, and stabilizing) all affect biodiversity. Speciation is the evolutionary process through which new species emerge. This affects biodiversity by resulting in the change of the existing species and the splitting of existing species into two or more different species. Directional selection is the process by which one of the extreme variations of a trait is favored. The results of directional selection are the evolution of a species and no increase in biodiversity. Disruptive selection is the process by which individuals with either extreme of a trait are favored. The affects of this are the evolution of a new species, genetic variation, and an increase in biodiversity. Stabilizing selection is a process by which average individuals in a population are favored. This results in no adaptive changes or evolution, the decrease in diversity, and the population looking more similar over time. As listed above, natural selection has several affects on biodiversity.

Answer 2

Speciation forms new species.Directional selection favors one extreme of a phenotype, which leads to evolution and adaptive change of a species.Disruptive selection selects against the average and leads to evolution and genetic variation of a species.Stabilizing selection favors the average individual in a population, which does not lead to adaptive change or evolution, and reduces variation.