How hard would you be to replace?
Not in a job interview sense. In the other sense. The romantic one.
If your partner lost you tomorrow, how difficult would it be to find someone with your face, your emotional steadiness, your bank account? Would it be, as Beyoncé once said, “I could have another you in a minute?”
Now answer it about your partner. Now notice which of those two numbers is bigger.
According to new research, that gap, or more precisely, which side of it you believe you’re on, tracks something you can hear through the wall: how much a couple fights.
The people who rated themselves as the more replaceable partner reported more conflict and more rivalry-vigilance. And it held whether the relationship was strictly monogamous or fully open.
The study comes from Faith Swanson, a researcher in the psychology department at Texas State University, working under Rhonda Balzarini, a Texas State professor affiliated with the Kinsey Institute, with the results published in the journal Evolution and Human Behavior.
Swanson’s starting point was a blind spot she’d been circling for a while.
“Humans have a long history of flexible mating arrangements, “she told PsyPost, “and yet relationship science still runs almost entirely on monogamous couples.”
She wanted to know whether the evolutionary machinery behind jealousy, conflict, and mate guarding operates the same way in consensually non-monogamous relationships, or whether people in those arrangements adapt out of it.
So the team recruited both. The final sample: 312 people in monogamous relationships and 200 in consensually non-monogamous ones, pulled from social media and online forums across 62 countries, averaging about 35 years old. Worth knowing for calibration: the group skewed white, female, and European or North American, which is a real limit on how far the findings travel.
The non-monogamous group wasn’t a curiosity add-on. It was the stress test.
In a monogamous relationship, your rivals are hypothetical. You imagine them. In an open one, your partner’s other partners have names, faces, and dinner plans. If feeling outranked drives conflict, this is the population where the comparison is happening in broad daylight, so it’s exactly where the effect should show itself.
The measurements were unusually concrete for a topic this squishy.
Participants rated the replaceability question across specific domains: physical attractiveness, emotional stability, financial resources.
Psychologists call the underlying quantity mate value, and the gap between yours and your partner’s a mate value discrepancy. It’s an unromantic vocabulary for something everyone has privately computed at 2 a.m.
Then came the behavioral inventory. How often do you and each partner fight? How distressed would you be if a partner got intimate with someone else? And, most tellingly, how often do you do things to keep your partner, which research splits into two families with wonderfully honest names.
Benefit-provisioning tactics are the sweet ones: gifts, affection, visible love and care.
Cost-inflicting tactics are the other ones: monopolizing a partner’s time, bad-mouthing potential competitors.
The survey also measured intrasexual competitiveness, the tendency to scan people of your own sex as rivals.
And the non-monogamous participants answered a further battery about how their relationships actually run: whether they disclose attractions, discuss jealousy openly, rank partners into a hierarchy, share money and time across partners, would help raise a partner’s children, and whether they experience compersion, which is the genuinely remarkable capacity to feel happy when your partner is romantically involved with someone else.
Across both relationship structures, people who saw themselves as lower in mate value reported more conflict with their partners and more competitiveness toward potential rivals.
Swanson’s evolutionary read “if you feel like the more replaceable half of a pair, your threat-detection system has ancestral reasons to run hot, because losing a valuable partner once carried survival-level consequences.”
A threat system running hot doesn’t announce itself as fear. It comes out as friction. The checking, the testing, the argument about the dishes that was never about the dishes.
But the study’s most useful finding is the one underneath that.
It wasn’t the partner’s desirability doing the damage. It wasn’t even the size of the gap between the two people. The strongest signal came from self-perception alone. “How someone perceives their own value explains more about conflict and competitiveness,” Swanson emphasized, than how they rate their partners at all.
Sit with what that relocates.
The conflict generator isn’t dating someone out of your league. It’s your private, unaudited, quite possibly wrong assessment of your own league. Two people can be in the same relationship while only one of them is in the version where somebody is halfway out the door.
The team got surprised at least once, and Swanson was candid about where. Textbook theory says mate value gaps should crank up jealousy and mate-guarding in primary relationships. In this data, they mostly didn’t, at least not consistently. The reliable signatures of feeling outranked were conflict and competitiveness, not the possessive behaviors everyone expects.
Which suggests something worth filing away: romantic insecurity doesn’t usually look like jealousy. It looks like arguing.
The open-relationship data delivered its own set of twists.
First, the broad one: both men and women in non-monogamous relationships reported less sexual and possessive jealousy than their monogamous counterparts. Whatever else these arrangements involve, white-knuckle possessiveness isn’t their signature emotion.
Second, the practices mattered, in both directions. Non-monogamous participants who disclosed attractions, discussed jealousy openly, and experienced compersion reported less conflict and less jealousy. Swanson called this the encouraging part: the evolutionary machinery may be ancient, she noted, but how people manage it turns out to be flexible, shaped by communication, trust, and negotiation.
Meanwhile, one popular practice backfired. Explicitly ranking partners into a hierarchy, formally declaring one person primary and others secondary, was associated with more frequent conflict, more jealousy, and more mate guarding. Writing the insecurity into the relationship’s org chart apparently doesn’t neutralize it. It institutionalizes it.
Third, the strangest wrinkle in the whole paper. With secondary partners, the pattern flipped. People who saw themselves as higher in mate value than a secondary partner reported more conflict, jealousy, and guarding in that relationship, not less.
The researchers’ working theory: secondary relationships are newer and less stable, without the accumulated conflict-resolution history of an established pair-bond.
A person who feels like the more desirable one in a wobbly arrangement may feel entitled to a certain quality of treatment, or may simply expect the thing to collapse, and both expectations generate static.
Though a caveat rides along with this one: only 88 participants provided data on a second partner, so consider it a first sighting, not a settled fact.
The sex differences ran in old evolutionary grooves.
Men who rated their own value as low were more likely to see other men as competitors, consistent with a heightened need to fight for access.
Women in monogamous relationships showed the mirror image: more competitiveness when their partner was highly desirable, which the researchers read as long-term-oriented guarding of an established bond worth keeping.
And then Swanson did the thing that separates good researchers from good marketing, which is spend the last quarter of her own press cycle shrinking her claims.
The effects were relatively modest, she pointed out, which is normal in relationship research because relationships are absurdly complicated. Mate value perception is one cue among many, sitting alongside attachment style, trust, personality, communication, and shared history.
The study is also a single cross-sectional snapshot, so the causal arrow is genuinely unknown. It’s entirely possible, she warned, that living inside constant conflict erodes your sense of your own value, rather than a low sense of value producing the conflict.
Notice that this reversal is, if anything, the kinder reading. It would mean the feeling of replaceability is a symptom of the fighting, not an accurate self-appraisal.
Her next step is the obvious one and the expensive one: longitudinal data, collected from both members of a couple instead of one partner’s perspective, to catch the dynamic actually moving.
Until then, here’s the kitchen-table translation of what the study suggests:
If one person in a relationship keeps generating friction out of proportion to its triggers, the productive question is probably not “why are you like this.”
It might be “do you actually know how hard you’d be to replace.”
Because the quietly hopeful finding in this study came from the people whose relationships force the issue into the open. The non-monogamous participants who talked about jealousy directly, on purpose, before it curdled, had measurably less of the conflict it produces. The sense of being replaceable may have roots older than language.
The conversation that defuses it, apparently, is available in any relationship that’s willing to have it.
