Genetic Explanations

Why human societies dislike female sexual promiscuity – an evolutionary explanation

Throughout human history men have needed to control women’s sexuality.  When women have a baby they are 100% sure that it is theirs.  For nearly all of the 200,000 years of their existence, human males have never really known if their child is truly their biological heir.  This is despite the reassuring knee jerk exclamations we hear from midwives, mothers and female relatives as soon as they clap eyes on the newborn infant: “oh, he / she has his father’s eyes!”

For good evolutionary reasons no man will want to spend time and resources inadvertently bringing up another man’s child.  A child that contains another man’s genes.  This is particularly important when title, wealth and inheritance are involved.  Consequently, to make sure that they knew who was the father, human civilizations created intricate ways to ensure female sexuality was monitored and controlled – doubly so when title, wealth and inheritance was involved.  Promiscuity in women was brutally discouraged.

The senior female members of these societies would also connive and reinforce this controlling behaviour.  No mother or grandmother wants to be duped by the women of their male heirs.

Women also have a vested interest in ensuring that sex is relatively rare in their society, as it increases their bargaining power with men.  Promiscuous women lower the price.

The major religions quickly wove this female controlling behaviour into their doctrines.  They constantly remind women that God will know what they were thinking, let alone what they might do in secret, in order to terrify and deter them from behaviours that could create doubt regarding paternity.  God had a plan for creation and how we humans ought to behave.  Religion was positioned as the only route to understanding God’s mind as only religion knew what He intended.  Religion therefore expropriated “morality”, which was a code of behaviour that God had intended and endorsed for humankind.  Female sexual activity and morality became inextricably linked.  Virginity became a virtue and promiscuous female sexual behaviour would ensure social exclusion, death by stoning or a quick trip to the asylum.  God followed up these human punishments with eternal damnation.

The potential for disease and the risks of unwanted pregnancy would also add to the general distaste societies feel towards promiscuous women.

In the animal kingdom male mammals will aggressively police their harems from unwanted competitive male interest and ensure their females are not exposed to, or tempted by, other males.  Any male that successfully deters other males and controls his females will be reproductively more successful, passing on more of his own genes into future generations,  thereby perpetuating and amplifying this behaviour.  Evolution does not need a cognitive intent in order to evolve these types of protective male behaviours.  The mechanism of evolution by natural selection will do that all on its own.  These behaviours are genetically inherited and hardwired across the animal kingdom and have evolved over 3,500,000,000 years.  Mankind has not been immune to these evolutionary pressures.

So how effective have these strict social conventions been at preventing men being cuckolded?  We can now measure how faithful British women have been since the Norman invasion of 1066.  Since this date men have inherited two things unchanged from their father – their Y chromosome and their surname.  By looking at the sequences of Y chromosomes and matching them to surnames we may see one of two things:

1. A few distinct Y chromosomes associated with particular surnames indicating faithful women. i.e. the surnames of the son were correctly allocated to the right father for the last 1000 years.


2. Many different Y chromosome associated with a surname indicating women who cuckolded their husbands.

Consider now which you think women have been for the last 1000 years before scrolling down, faithful or unfaithful?………….………

Women have been ludicrously faithful to the point we wonder if the little variation in Y chromosomes associated with surnames could be caused by legitimate adoption.  Cuckolded fathers are rare now, and were equally rare in the past.  Studies show it is 1-3% per generation*.

This strong emotional distaste of promiscuous women and the consequent desire to control female sexuality, at almost any cost, has been ingrained in every human society and every major religion.  The very recent inventions of DNA testing, reliable contraception and antibiotics will not totally undo 3,500,000,000 years of evolution.


Further reading:

Women reject sexually promiscuous peers when making female friends

Female Bitchiness and Unsisterly Behaviour – An Evolutionary Explanation

Prostitution and Liberty

Women are either bisexual or lesbian, but rarely straight.


Infidelity – The Economist

Surnames and the Y Chromosome