Are We Humans Truly Naturally Monogamous? Or Are We Just Lying to Ourselves?

Every time an infidelity scandal breaks, everyone around (often with a hint of schadenfreude) turns it into a massive spectacle. It doesn’t matter if it’s a Hollywood star or the neighbors from the third floor. Everyone recites the same script: “How could they? They were such a beautiful couple. They promised to be faithful…” But let’s put our hands on our hearts, throw naivety in the bin, and put pragmatism on the table. Does it really surprise anyone anymore?

If we take a closer look at our biology, evolutionary history, genetics, and the latest social trends, you might just be shocked.

Monogamy as a Modern Cultural Invention

If you thought humans lived in monogamous marriages since the dawn of time, history will quickly prove you wrong. Anthropologists estimate that more than 80 percent of known human cultures in history permitted polygamy. In fact, strict monogamy as we know it today is only about 1,000 years old. And why did it become the norm in the first place? Well, the answer is surprisingly pragmatic. Monogamy is a fantastic tool for stabilizing society.

What Does Mother Nature Have to Say?

If we were to take nature as our ultimate teacher, we would get a very quick lesson in polygamy. In the mammalian kingdom, monogamy is extremely rare. Only about 3 to 5 percent of mammalian species commit to a single partner for life. Our closest relatives, primates, fare slightly better — about 15 to 29 percent of them live in pairs. But it is still the overwhelming minority.

From an evolutionary standpoint, our species is somewhere in the middle. Taking into account sexual dimorphism — the differences in size between males and females — we can deduce a lot. In species where males fight aggressively for females, males are twice the size of females. In strictly monogamous species, males and females are the same size. And us humans? Men are, on average, 15-20% larger than women. This suggests that our ancestors were neither angelically monogamous nor extremely polygamous. Scientifically speaking, we were somewhere in between.

The Infidelity Gene: Is Our DNA to Blame?

Is it possible that infidelity is not just a moral failing, but also a biological urge? Scientists have indeed found a link between our genetics and the tendency to cheat. One of the genes responsible for this urge is a variant of the DRD4 gene, which affects dopamine receptors in the brain. People with a certain variation of this gene have a demonstrably higher tendency towards novelty-seeking, risk-taking, and — guess what — promiscuity and infidelity.

Genetics is not destiny; it is just a predisposition. However, it does explain why fidelity is such an incredible struggle for some people, while for others it comes naturally.

Ethical Non-Monogamy: A New Relationship Revolution?

With the growing realization that strict monogamy may not suit everyone, we are currently experiencing a fascinating phenomenon — the skyrocketing rise of ethical non-monogamy (ENM). This is not about secret cheating in hotel rooms. Ethical non-monogamy is built on absolute honesty, transparency, and the consent of all parties involved.

This trend has long ceased to be a fringe matter for hippies or the “elite”. According to recent surveys, up to 20 percent of North Americans have engaged in some form of consensual non-monogamy at some point in their lives. Even more shockingly, in 2024, nearly 1 in 3 unmarried Americans admitted to having experience with such a relationship.

Dating apps are reporting massive surges. One of them even recorded a 500 percent increase over the last three years in users who included terms like “ethically non-monogamous” or “polyamorous” in their profiles.

And do you know what the most interesting part is? Research shows that people in these relationships are no less happy. On the contrary. Studies suggest that people in consensual non-monogamous relationships often report the same levels of love and satisfaction as monogamous couples, but at the same time report higher sexual satisfaction, better communication, and — paradoxically — lower levels of jealousy. This is because these individuals have to learn to communicate about their feelings and boundaries so openly that many traditional couples never achieve it.

While for many the thought of their partner in someone else’s arms is a nightmare, for ENM practitioners, it is a way to relieve their relationship of unrealistic pressure. After all, how often do we expect our partner to be our best friend, passionate lover, financial advisor, therapist, and flatmate all rolled into one?

Are We Hypocrites?

Let’s face the truth. We live in a society that not only demands monogamy but practically glorifies it. The reality, however, is different. The divorce rate is astronomical, and statistics on infidelity state that roughly 20 percent of people in monogamous relationships will cheat on their partner at least once.

Evolutionary biologist David Barash summed it up perfectly: The fact that monogamy is not “natural” for our species does not mean it is not possible or desirable. We fly in airplanes, operate on brains, and play the violin. None of this is “natural”.

Monogamy is similar. It is a choice. It is a commitment that requires work, sacrifice, and a conscious decision to go against our most basic biological instincts. And perhaps that is exactly where its true beauty lies. Not in the fact that it is our biological destiny, but in the fact that we as a species have chosen to rise above our animal instincts (at least most of the time) to create something deeper and more stable.

Whether you choose strict monogamy or join the growing trend of ethical non-monogamy, one thing is certain: human sexuality and relationships are far more complex than could fit into a simple fairy tale about living happily ever after.

So, are we naturally monogamous? Probably not. But we are intelligent enough to choose who we want to be.

Whatever you choose — own it. No shame, no apology. Want to understand your desires, your relationships, or your intimacy a little better? That’s exactly what we built Lusole for. Come explore.

Yours, Monika