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5 Ways Your Ancestral Past Is Messing with Your Love Life

Are our stone-age brains ill-equipped for modern mating?

Key points

  • Humans evolved in small scale societies very different from modern Western culture.
  • These differences (called evolutionary mismatch) challenge our mating psychology.
  • These include too many options, anonymity, and autonomy in the mating market.
  • Knowledge of mismatch could point to options for making mating easier in the 21st century and beyond.

According to some evolutionary theorists, humans possess a stone-age brain, built for tackling stone age problems in stone age contexts. But what happens when those problems and contexts change dramatically? You get something called evolutionary mismatch.

Change over time

Here’s the issue: when parts of the environment stay the same for a long time, organisms evolve to thrive in that environment—both physically and mentally. Giraffes evolved long necks because tall trees were a consistent presence throughout their evolutionary history. Longer-necked giraffes had better access to food, which then allowed them to survive and pass their long-necked genes to subsequent generations. Similarly, the blind cave fish lost its sight after generations of cave-dwelling.

Pulling the rug from under you

But what happens if the environment changes drastically at speeds too fast for evolution to take place? In some cases, you end up with highly specialized tools being made redundant. Long necks confer little advantage to giraffes if trees disappear and the only food available is a few feet off the ground.

In other cases, these tools can lead to harmful behaviors that get in the way of survival and reproduction. Humans, for example, have a massive drive towards sugary and fatty foods because we evolved in a landscape where these things were hard to come by.

Now that Oreos can be bought at gas stations at 2 a.m., our desire for them doesn’t just switch off. We still approach these foods like they’re rare treasure, leading to the consumption of calorie-dense foods well beyond our needs.

What other types of mismatch are there? Inspired by a recent theoretical article on evolutionary mismatch, I'm going to run down my top five things that make modern mating complicated.

1. Too many people

Humans evolved to function in small communities, maxing out at around 150 people. That’s enough for everyone to know each other and is conducive to forming close relationships. Applying small-scale psychology to large social networks doesn’t always work well.

For one thing, we are surrounded by more people than we could ever build meaningful relationships with. This can lead to a collection of lots of superficial relationships that can leave people feeling like their friendships are hollow and unsupportive. A related problem is that large networks of contacts on social media can give people we’re not really close to (and may never meet) a platform to influence our mating. A seemingly necessary part of any relationship advice forum are those users who urge people they don’t know or care about to break up with their partner for any transgression no matter how small.

2. Relationships can be temporary

Are you someone who dreams of commitment but only finds one-night stands? Related to the “too many people” problem is the fact that with large numbers of relationships comes the opportunity for people to retain a level of anonymity and to easily come and go from people’s lives.

In our ancestral past, sexual relations led to relationships much more regularly, and even when short-term liaisons occurred, our casual partners remained close at hand. Large modern societies make it easy for people to “ghost” and we haven’t quite adapted to cope with that yet.

3. Too much autonomy

For most of our history, mate choice wasn’t a solitary decision. Your family would often get involved. To some, this might sound like hell. However, forgoing the experience of elders means figuring out who is good for you through trial and error.

This comes with its own problems, including attracting and flirting with others; discovering your mate preferences and priorities; figuring out the preferences of your potential suitors; establishing red flags; and learning about what makes two people compatible in a long-term relationship.

Drawing upon the experience of others who have your best interests at heart can be a useful shortcut in what is otherwise a steep learning curve.

4. Not adulting

For a variety of reasons, children are leaving home, settling down, and having children later and later. There are even terms like “growing-ups” (as opposed to grown-ups) or “failed fledglings” used to describe those who stay at home with parents well into their adulthood.

In the ancestral past most 20-year olds would be seasoned parents, and their fathers and mothers would be young enough to provide considerable help with childcare. Western society allows for “adulting” to be put off for decades, completely changing this dynamic. For example, putting off having children means that when some couples finally decide to start a family, they might find themselves not only looking after their progeny but their parents as well.

5. Information overload

If you have ever been in a supermarket and found it hard to decide which item to buy, or even felt dazed by the number of results returned on a dating website, then you might be suffering from “choice” or “information” overload.

Mate choice was often limited to a handful of options in the Pleistocene epoch. Selecting from a large pool of suitors is a relatively “new” concept. And the way the mind deals with a large number of choices is very different from how it deals with a smaller number.

For example, it might cause people to adopt abnormally high standards to cut this number down, or it could lead people to feel overwhelmed, freeze, and do nothing.

The bottom line

There are a lot of things about modern Western societies that are at odds with the types of environments our ancestors lived and thrived in, and these differences have implications for how we seek and form relationships. Knowledge of these differences might give us inspiration for steps we can take to make mating easier—such as using the experience of others to avoid learning through trial and error and looking for long-term partners within our social circles to avoid issues of anonymity.


Goetz, C. D., Pillsworth, E. G., Buss, D. M., & Conroy-Beam, D. (2019). Evolutionary mismatch in mating. Frontiers in Psychology, 10, 2709.

Dunbar, R. I. (2014). The social brain: Psychological underpinnings and implications for the structure of organizations. Current Directions in Psychological Science, 23(2), 109-114.

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