Perhaps PMS in women has developed as a useful adaptation in the course of evolution: a nervous and aggressive state helps a woman get rid of a bad partner, finding a more worthy one in his place, and thereby improve the genetics of children.
This phenomenon is inevitable, like death and taxes, and not that much more pleasant. Every month, hundreds of millions of women feel that everything is wrong – the husband is not the same, and the children are not the same, and the work is not the same, and the taste in the mouth is not the same, and the whole life is not the same. Why did nature need to regularly torture women? This is all the less understandable if we remember that the females of most other mammalian species do not suffer from anything like this.
Australian biologist Michael Gillings Michael R. Gillings has put forward a hypothesis that explains PMS by linking it to a trait that is missing in most animals – stable alliances between partners.
According to his research, published in the journal Evolutionary Applications*, premenstrual syndrome (PMS) is an evolutionary adaptation that allowed a woman to increase her chances of having children.
Since a woman’s breakup with a partner she no longer loves often occurs precisely during the PMS period, the scientist suggested that this period serves as a tool of natural selection, with which a woman gets rid of a man who cannot give her offspring.
It is difficult for us modern people to understand how PMS and childbearing are related. It is clear that PMS is absent during pregnancy – after all, there are no periods either. But after the child is born, the cursed state regains its former regularity. Where is the connection?
Meanwhile, for any ethnologist who studies the life of primitive hunters and gatherers, it is obvious. Women of reproductive age in such tribes practically do not have periods, since they are constantly either pregnant or breastfeeding (during lactation, the level of hormones in the blood inhibits the formation of an egg and menstruation may not occur for several months).
That is, in ancient times, PMS was mainly the property of girls who do not yet have a partner, and women living with an infertile partner. The regularly recurring bad period served to encourage them to get mad at their partner more often and one day leave him.
Among the first of our species’ foremothers, the hormonal mechanism that causes premenstrual syndrome may have occurred in literally a few, but these units nevertheless had an important evolutionary advantage. This means that the genes that predispose to this evolutionary mechanism must, over time, spread more and more widely in the population. Eventually, PMS became as normal for women as, say, breastfeeding.
Perhaps the hypothesis put forward by Michael Gillings will allow women to come to terms with the condition, which the Chinese have given the apt name – “old girlfriend”. To paraphrase a phrase from the novel by HG Wells, we can say: “For a woman does not tear and rush in vain.”
See also: “For two months I stopped being myself”
True, the author notes that the aggressive behavior of a woman during PMS can be beneficial for her genes only if we are talking about a couple who does not have children. In a couple where there are children, a woman’s monthly aggression towards her partner can lead to his departure and, as a result, a decrease or complete cessation of his care for children.
Then the effect will be just the opposite. If we imagine that modern society exists on the same grounds (in particular, a woman is not obliged to give birth every year) for at least several hundred thousand years, PMS will play the role of a non-adaptive factor, which means that an ever smaller number of women will carry genes that predisposing to him. And sooner or later the human race can get rid of it completely.
* M. Gillings «Were there evolutionary advantages to premenstrual syndrome? Evolutionary Applications», Аugust 2014.