Making Young from Old: How is Sex Designed to Help?

Gametogenesis and syngamy are shown to incorporate, as key elements in their design, structures and processes that help to prevent age-related deterioration that accumulates in adult somas from being transferred directly to newly formed offspring. As such, in addition to producing new gene combinations, sex increases the separation of germ and soma. It follows as a central prediction that offspring of a species that has recently abandoned sex will manifest early in life some of the dysfunctions that formerly manifested only much later in life. These dysfunctions, which can include early onset of age-linked diseases such as cancer, should impede transitioning to non-sex, and therefore would help to account for sex's maintenance. Evidence is reviewed, and found generally to support the hypothesis.