How does polygenic inheritance contribute to evolution?

Polygenic inheritance plays a significant role in evolution by creating continuous variation in traits, which is crucial for the process of natural selection. In polygenic inheritance, multiple genes contribute to a single trait, resulting in a smooth distribution of phenotypes rather than distinct categories. This continuous variation allows populations to exhibit a range of traits, such as height or skin color, which can be advantageous for survival and reproduction in changing environments.

Natural selection acts more effectively on traits that show a range of variation. When individuals in a population possess different phenotypes, selection can favor certain variations over others, ultimately leading to changes in allele frequencies over time. This dynamic process can enhance a population's ability to adapt to environmental pressures, drive speciation, and shape the evolutionary trajectory of a species. Therefore, polygenic inheritance facilitates the raw material that natural selection can work with, asserting its vital contribution to the evolutionary process.