08:56 15 June 2013
For years, scientists have no definite explanation as to why menopause affects the entire female population. However, a recent study with the use of computer modeling may shed some light.
The study aimed to assess how men’s preference to breed with younger women have resulted to menopause among older women.
Professor Rama Singh, from Canada’s McMaster University, said that when men prefer younger mates, fertility becomes pointless for older women.
He said: “Menopause is believed to be unique to humans, but no one has yet been able to offer a satisfactory explanation for why it occurs.
“How do you evolve infertility? It is contrary to the whole notion of natural selection. Natural selection selects for fertility, for reproduction.”
Previous theories focused on “grandmother effect” which suggests that when women reach certain age when they might not live to see a child grow, they become part of social groups where they help rear their grandchildren.
Meanwhile, Dr Maxwell Burton-Chellew, evolutionary biologist at the University of Oxford, is skeptical about the findings.
He said: “The authors argue that the menopause exists in humans because males have a strong preference for younger females.
“However, this is probably the wrong way round - the human male preference for younger females is likely to be because older females are less fertile.
“Even if this study is correct, it fails to explain why the menopause is so rare in the animal kingdom.”