Because natural selection can only increase or decrease frequency of alleles that already exist in the population
<span>The 1960 Chile earthquake was a magnitude 9.5 the largest earthquake ever recorded!</span>
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<span>The Renal organs filtrate the blood and maintain homeostasis in the body by regulating the PH of the blood. If the body has an excess of na+(Sodium), then the renal clearance of na+ will be of a higher rate. Conversely, if the na+ values in the blood are low, than the kidneys will reabsorbed more na+.</span>