Answer:
A polygenic trait can be described as a physical trait which is influenced by more than one gene.
The three types of selection for a polygenic trait are:
1) Directional Selection: In a directional selection, one of the phenotype is favored in an ecosystem. As a result of this favoring, the allelic frequency changes and shifts in favor of this particular trait.
2) Stabilizing selection: It is a type of natural selection in which the intermediate trait is favored. The population carries a middle trait in abundance.
3) Disruptive Selection: Disruptive trait is a type of natural selection in which the traits on the extreme sides are favored. The intermediate traits are less favored.
What makes studying people difficult is that you are yourself. You will always be different from other humans, so studying them naturally takes you out of your comfort zone
