Given a scientific passage and an answer, generate a question for the given answer.
Q: Passage: Traits that are affected by more than one gene are called polygenic traits . The genes that affect a polygenic trait may be closely linked on a chromosome, unlinked on a chromosome, or on different chromosomes. Polygenic traits are often difficult for geneticists to track because the polygenic trait may have many alleles. Also, independent assortment ensures the genes combine differently in gametes. Therefore, many different intermediate phenotypes exist in offspring. Eye color ( Figure below ), and skin color are examples of polygenic traits in humans. Answer: polygenic traits
A:
Traits that are affected by more than one gene are what type of traits?