Menopause, with its dreaded hot flashes, sleep problems and more, now comes with at least one conciliation for women: It’s all men’s fault, according to new research.
Human male preference for younger women has actually stacked the Darwinian deck against continued fertility in older women, concludes the study, published in the latest issue of PLoS Computational Biology.
“I think male-driven sexual selection, the male sex drive, has been a major factor driving sexual selection in humans,” co-author Rama Singh told Discovery News, adding that if “there were no preference against older women, women would be reproducing like men are for their whole lives.”
Singh, an evolutionary geneticist at McMaster University, conducted the research with colleagues Richard Morton and Jonathan Stone. They used computer simulation to mathematically model how genes change over time among mating pairs and others in a given population.
“Mating preference in males for younger females relaxed selection on older females,” co-author J.R. Stone, associate director of McMaster’s Origins Institute, told Discovery News.
In short, these older gals tend to be dumped or ignored in favor of younger women, who in theory have better genes and can, because of their age and energy, possibly reproduce more, keeping the male’s lineage going.
Women, of course, don’t just drop dead after menopause. The forces of natural selection seek only the survival of the species through individual fitness. They protect fertility in women while they are most likely to reproduce, but after that period, they cease to quell the genetic mutations that ultimately bring on menopause and a possible host of other potential health problems, such as increased risk for heart attack and stroke.
Human, and killer whale, females, who also go through menopause, often live long lives after their baby-producing days are done. They even continue to increase the propagation of their genes during later life.