Natural selection could not occur without environment, and a act on animal.
The answer is parasitism. It is the relationship where the Mosquitoes feed on the blood of other animals and humans. which often leaves the host organism with a rash, or a disease may be transmitted to them. Parasitism<span> is a relationship between species, where one organism, the parasite, lives on or in another organism, the host, causing it some harm,</span>
Explanation:
Results in a decline in CD4+T cell numbers below the critical level, and loss of cell-mediated immunity. Therefore the body becomes progressively more susceptible to opportunistic infections and cancer.
