Complex traits do not follow the restrictions of dominant and recessive like monogenes do, instead they have variations. With these traits each organism can show a different version of the same gene. A simple example would be eye color, if we follow the logic that genes cannot be complex then each person on earth would have brown, or blue eyes. Now this is just not true and the mixed colors that are created such as hazel, green, or gray express the way complex genes work. Complex traits are a mixture of different alleles working together which allows variation in things such as eye color. So a mixture of brown and blue alleles could make a color that seems to hazel or gray depending on which genes shine through. This can also cause a child to have blue eyes even if both parents have brown. Another example would be schizophrenia, this mental disorder can run in families yet all of its members are not destined to develop the disease. It is even possible for one identical twin to get schizophrenia while the other does not. This is because complex traits are determined by many factors from what alleles are available to what food a person tends to eat. Schizophrenia can also show up in a person with no family history of the disease which is another important characteristic of complex traits. The understanding of complex traits will help to expand the study of genes and genetic diseases.