Evolution Blog 5-- Ch 16 Write a summary of how natural selection works on polygenic traits Use 16-6 thru 16-8 to help you

Natural selection can affect the distribution of phenotypes in three ways which are directional selection,stabilizing selection or disruptive selection. Directional selection occurs when individuals at one end of the curve have a higher fitness than individuals in the middle or at the other end and it allows the range of phenotypes to shifts to fail and succeed. Creating new traits and needs as a result. Stabilizing selection allows situations to become stable as individuals have a higher fitness then others. This results in the idea of balance in traits that are spread out with polygenic traits. Disruptive selection takes place when individuals at the higher and lower end have higher fitness than the ones in the middle allowing population splits to create polygenic traits.