Answer:
Skin pigmentation in humans
Step-by-step explanation:
Skin pigmentation is a very common example in polygenic inheritance. This inheritance is represented by two gene pairs: Aa and Bb.
Thus, A and B determine the production of the same amount of melanin pigment and have additive effect. Therefore, there are several shades of color in human skin, according to the amount of genes A and B.
Offspring of parents with one very dark skinned and one very light skinned may give an intermediate skin color. Heterozygous parents for skin color can lead to offspring with darker or lighter skin than their own.