Is Monogamy Natural? Science Says... It’s Complicated

“I Love You… But Also, That Person’s Hot”

Ever been wildly in love and still caught yourself crushing on a barista with great eyebrows?

Welcome to the human condition—beautiful, complex, and deeply contradictory.

For centuries, we’ve been sold the monogamy fantasy: find The One™, settle down, ride into the sunset holding hands and never get butterflies for anyone else again.

But is that how we’re really wired?

Or is it more social contract than biological blueprint?

Let’s unravel the tangled sheets of love, lust, loyalty, and what science says about monogamy—and why it might not be the “default setting” we think it is.

What Even Is Monogamy?

Monogamy is usually defined in two ways:

• Social monogamy: Being romantically partnered with one person at a time (but maybe not sexually exclusive).

• Sexual monogamy: Being romantically and exclusively sexually involved with one person—forever, ideally.

Fun fact: they’re not the same, and few species do both.

Meet the Prairie Vole: Monogamy’s Mascot

Prairie voles are one of the rare species that pair bond for life. They:

• Nest together

• Raise babies as a team

• Reject new mates after bonding

Why? Because their brains release oxytocin and vasopressin during sex, locking in loyalty like neurochemical duct tape.

Humans also release these hormones—but here’s the twist: our response is way more variable.

Which means some of us are voles…

And some of us are bonobos with WiFi.

Most Animals? Not Monogamous. At All.

The vast majority of mammals are not monogamous:

• Lions? Multiple lionesses.

• Dolphins? Casual and frequent.

• Chimpanzees? Massive group orgies (seriously).

Even birds—long thought to be loyal lovers—have been outed by DNA testing. Around 90% of bird species engage in extra-pair mating, meaning they mate outside their “pair bond.”

So biologically? Sexual variety is the norm, not the exception.

The Human Brain: Built for Both Bonding and Variety

Humans have a brain that’s deeply conflicted:

• Oxytocin bonds us to partners

• Dopamine makes us chase novelty

• Serotonin stabilizes love

• Testosterone/estrogen keep libido alive

This means you can:

• Be emotionally attached to one person

• Fantasize about another

• Still be faithful—because you choose to

Monogamy isn’t instinctive. It’s elective. That’s what makes it meaningful when it works.

A Brief History of “Till Death Do Us Part”

• Ancient cultures like Greece and Rome were not strictly monogamous.

• Biblical times? Polygamy was totally a thing.

• Monogamy as a legal norm? Mostly a product of property rights, inheritance, and later, Christian moral codes.

• Modern romance? Fueled by Victorian sentiment, Hollywood fantasies, and heteronormative pressure.

So the idea that monogamy is “natural”?

It’s more historical narrative than scientific truth.

So… Is Non-Monogamy More Natural?

Let’s clarify: “natural” doesn’t mean “better.”

But humans are definitely capable of:

• Loving more than one person at once

• Separating sex from emotional attachment

• Creating bonds outside rigid romantic hierarchies

That’s why ethical non-monogamy, open relationships, and polyamory have been gaining traction. Not as rebellious alternatives, but as intentional structures that reflect how people actually feel.

Why Do People Cheat, Then?

Studies show most people who cheat:

• Aren’t sexually dissatisfied

• Still love their partner

• Want variety, not replacement

It’s less about leaving someone and more about fulfilling needs they don’t know how to express.

Monogamy isn’t broken. But our communication around desire? Often is.

Can Monogamy Still Work? Absolutely.

Here’s the key: monogamy works best when it’s:

• Chosen, not assumed

• Discussed, not dictated

• Flexible, not fantasy-based

It’s not about being “not attracted” to others. It’s about commitment over impulse, transparency over secrecy, and emotional security.

Monogamy can be beautiful. But it should be built with eyes wide open, not closed.

How to Navigate Modern Love (Monogamous or Not)

• Define your terms: What does loyalty mean to you? Is it sexual? Emotional?

• Talk about it: Have “the monogamy conversation” early. Don’t assume.

• Get curious: Jealousy is natural—but it's also a clue.

• Check in often: Relationships evolve. So should the agreements within them.

• Respect desire: Wanting someone else isn’t betrayal. Acting without consent is.

Monogamy Isn’t Natural. But Neither Is Polyamory.

What is natural?

• Wanting love.

• Craving connection.

• Feeling desire.

• Being confused by all of the above.

Humans are messy, beautiful contradictions.

So whether you’re a diehard monogamist, curious explorer, or practicing polyamorist, the real question isn’t “What’s natural?”

It’s:

“What’s honest, healthy, and aligned for you?”

Because when it’s chosen with love, any structure can be sacred.