Selection is the functional relationship between phenotypes and fitness. Natural selection is the production of organisms based on their physical attributes whereby the descendants of younger generations take on the strong, desired, and heritable aspects of their parents. They adapt better to the environment, although some perform better than others based on the individual traits attributed to their phenotypes (Sinervo, 1997). According to Charles Darwin, fitness can be described in three different forms of selection that interfere with the average of the phenotypic traits of a population. They include: directional selection; stabilizing selection; and destructive selection. Long-term directional selection can lead to the formation of new organisms from the existing one because traits are linearly related to fitness. Stabilizing selection instead leads to the refinement of the existing type by eliminating the extremes in a distribution of phenotypes. The third selection trait, destructive selection, can lead to the formation of two new types of species...