Menopause: Can We Blame Men?
What is Menopause?
Menopause is a natural process that occurs in women typically between the ages of 45 and 55. It marks the end of a woman’s reproductive years and is characterized by a decline in the production of the hormones estrogen and progesterone. This decline leads to a number of physical and emotional changes, including:
- Hot flashes
- Difficulty sleeping
- Reduced interest in sex
- Increased vaginal infections
- Mood swings
- Fatigue
Why Do We Have Menopause?
Scientists have long debated the reasons why humans have menopause. One common hypothesis is the grandmother hypothesis, which suggests that menopause evolved to allow older women to help raise their grandchildren, thus increasing the survival chances of their genes.
However, a recent study published in the journal PLOS Computational Biology challenges this hypothesis. The study’s lead author, Rama Singh, argues that the grandmother hypothesis does not explain how the genetic mutation causing sterility in older women became so common in the first place.
Male Mate Choice and Menopause
Singh’s study proposes a different hypothesis: that male mate choice may have played a role in the evolution of menopause. Men tend to prefer younger females as mates, and this preference may have led to the accumulation of mutations that harmed the fertility of older women over time.
The study’s computer simulations showed that when male mate choice was added to the model, there was an increase in mutations that reduced fertility in older women. These mutations eventually became fixed in the population, leading to the evolution of menopause.
Evidence for the Male Mate Choice Hypothesis
While the male mate choice hypothesis is still a theory, there is some evidence to support it. For example, studies have shown that men are more likely to rate younger women as more attractive and desirable. Additionally, men are more likely to have children with younger women than with older women.
Menopause in Other Species
Humans are not the only species that experience menopause. Some primates, such as rhesus monkeys and chimpanzees, also go through menopause. However, menopause is almost uniquely human in that it occurs so late in life. The reasons for this difference are not fully understood.
Conclusion
The exact reasons why humans have menopause are still a matter of debate. However, the male mate choice hypothesis is a promising new theory that could help to explain this evolutionary puzzle.
