A study from Stanford University and the University of California Santa Barbara shows that relationships of older men partnered with younger women (so-called May-December relationships) tend to produce children that are likely to live longer.
The study helps explain away previous research that predicts a “Wall of Death” — that female menopause at about age 50 years should be followed by a sharp increase in mortality. Human lives do not experience that wall of death. This new study focuses on the biology of both sexes, not just the biology of women and menopause.
Women who can no longer reproduce cannot produce a child with longevity genes. Men partnered with menopausal women also cannot produce a child with longevity genes, since the woman cannot bear a child. However, an older man is likely to have longevity genes that may be passed on to future generations, and partnering with a younger woman makes this possible.
Male fertility can only result from matings with fertile females, and the study present a range of data showing that males much older than 50 yrs have substantial realized fertility through matings with younger females.
Tuljapurkar SD, Puleston CO, Gurven MD (2007) Why Men Matter: Mating Patterns Drive Evolution of Human Lifespan. PLoS ONE 2(8): e785. doi:10.1371/journal.pone.0000785
Funding for this study is supported by U.S. National Institute on Aging grant 1 PO1 AG22500-01 and NIA grant R01 AG024119-01.