Answer:
Stabilizing selection results in a decrease of a population 's genetic variance when natural selection favors an average phenotype and selects against extreme variations. In directional selection, a population's genetic variance shifts toward a new phenotype when exposed to environmental changes.
Explanation:
I don't bite, don't worry
<span>Commensalism is an interaction in which one of those species would benefit, and the other one would not be affected. Parasitism is an interaction in which one of those species would benefit at the expense of the host organism. Thus, in commensalism we have one positive and one neutral result while in parasitism we have one positive and one negative result.</span>