Menopause Evolved to Prevent Competition between In-Laws
She constantly criticizes me, she complains about my housekeeping skills, I'm a bad cook, horrible mother and her son is too good for me. Many daughter-in-laws have experieinced one or more of these barbs by her husband's first love--his mom.
The mother/daughter-in-law relationship can be a complex one, often involving many a ruined Thanksgiving gathering, but a new study may shed some light on this tension and may help explain a biological imperative present in human females that does not exist in any other species, including the human male.
The biological process known as menopause may have evolved, in part, to prevent competition between a mother and her new daughter-in-law, according to research published today (23 August 2012) in the journal Ecology Letters.
The study - by researchers from the University of Turku (Finland), University of Exeter (UK), University of Sheffield (UK) and Stanford University (US) - offers an explanation for why women experience this life-changing event.
The research showed that when grandmothers and their daughter's-in-law were both pregnant at the same time, each newborn's survival rate dropped by 50%. Interestingly, when the women were biologically related, such as a mother and daughter, this was not the case. This may be due to increased competition for resources for one's own child, which does not exist when the women are related and are much more cooperative.
A child born to families with a mother-in-law and daughter-in-law reproducing simultaneously was twice as likely to die before reaching the age of 15.
However, this was not the case in the instances when a mother and daughter had babies at the same time. This suggests that related women breed cooperatively and unrelated women do not.
Co-author Dr. Andy Russell from the University of Exeter's Centre for Ecology and Conservation said: "We are so used to the fact that all women will experience menopause, that we forget it is seriously bizarre. Evolutionary theory expects animals to reproduce throughout their lifespan, and this is exactly what happens in almost every animal known, including human men. So why are women so different? Our study shows for the first time that the answer could lie in the relationship between a mother-in-law and daughter-in-law."
the study provides scientific proof that your cub-making days are numbered and will eventually make way for your cougar years.