Why polygamy might be more natural than you thought

March 8, 2017

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Most theories of relationships centre on the idea that humans are well-suited for, and biologically disposed toward forming 'pair-bonds'. But these traditional anthropological and evolutionary perspectives on sex are facing a growing threat from a more recent contender. The idea that human promiscuity is our natural state and community-style lovin' better explains the state of our modern sexuality.


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You've probably heard the traditional views on sex and sexuality. Perhaps you've been told that humans are driven to form monogamous relationships, a common anthropological assumption. You might know the evolutionary perspectives that have it slightly differently; men and women are driven to sleep around but secure at least one partner to get that oh-so-sweet security. Both theories centre on the idea that humans are well-suited for, and biologically disposed toward forming 'pair-bonds'. But, as with any question of human psychology, any given theory must have an equal and opposite counter-theory. The traditional anthropological and evolutionary perspectives on sex are facing a growing threat from a more recent contender. The idea that human promiscuity is our natural state and community-style lovin' better explains the state of our modern sexuality.

Some revision

The classic anthropological perspective on human relationships holds that the nuclear family has been the cornerstone of human societies from the earliest times. Just explore Helen Fisher's TED talks on the topics. In her work with the Kinsey Institute (founded by Arthur Kinsey, the first scientist to really explore sex), and in her popular book "Anatomy of Love: A Natural History of Mating, Marriage and Why We Stray" Helen is adamant that monogamy is the rule, not the exception when it comes to human relationships. It's a common theme among anthropological work. A fantastic example of the influence of this assumption can be seen in Owen Lovejoy's 'Male Provisioning Model'. He suggests that monogamy is a crucial factor in our evolution from four-legged to two-legged movement, and can be traced back 1.8 million years. Evolutionary psychologists are similarly enthusiastic about the pair-bond. David Buss, being the most prominant name among the literature, proposed the 'Sexual Strategies' theory to explain why men and women seemed to have such different approaches to sex. The theory essentially posits that men are driven to sleep around in order to spread their genes as far and wide as possible. But, since it's hard for a mlae to know whether a child is really his or if it will live through those fragile early years, he'll pick one woman to build a family with. Make sure she's not having someone else's baby and protect her and his new progeny into the future. Women, in contrast, have different aims. They want a genetically healthy baby, so they'll sleep with the sexiest men (read: those with the most testosterone) but will look to settle down with a man who has lots of resources to take care of her and the baby during those vulnerable early years. Note that while the same man might be the protector and the baby-provider, they don't have to be, according to Buss. And so, while men and women both might have the urge to get around, both will eventually look to settle down.

A 'radical' new perspective

Now, one couldn't blame you if you're already picking holes in both perspectives. Certainly, the sexual strategies approach has been bashed, and there are many variations on the theme that equally explain the results of research in the area. And speaking anthropologically, there are many examples of cultures with unique and non-monogamous approaches to sex (as we'll get to in a moment). It is absolutely true to say that neither group has satisfactorily captured the human experience of love, relationships, and sex, as evidenced by the enormous amount of research that abounds on the topic. But recently, a new trend has started to gain momentum that I think is worth exploring here. Popularised by Chris Ryan and Cacilda Jethá in their recent book 'Sex at Dawn', the new perspective suggests that humans are naturally promiscuous and the trend toward monogamy is a cultural artifact, courtesy of the agricultural revolution. Proponents of this theory begin with the assumption that the hunter-gathering human was a fierce egalitarian. What was his, was everyone's. The only way such communities could thrive was by sharing the food that was collected and the workload that was required of them; distributing the risk maximised their survivability. Hoarding food was the highest crime, and selfish members would be exiled to meet their death in the wilderness. These aspects of early human communities are assumptions shared by many anthropologists, and examples of this in practice can be found in many hunter-gatherer communities that still exist today. However, the new perspective takes this a step further, suggesting that human sex was approached with a similarly socialist bent.

The (dare-I-say-it) logical extension of egalitarian resource sharing to the sharing of sex is supported by a number of anthropological and scientific observations. The first being the work conducted on the humble bonobo ape. Our closest ape relative, alongside the chimpanzee, bonobo females not only seek out sexual attention from many males (often at once), they also seem to be the dominant gender. The males tend to be submissive to the females, and females with the most influence seem to run the show. This isn't achieved through violence or displays of dominance (rare in bonobo world), but instead, through social interaction - who is most liked, is most followed. In bonobo groups, males (or females for that matter) don't fight over the opposite gender, but merely appear to have sex at a whim. In fact, bonobos do it missionary, like us; they french kiss, like us; and they gaze into each other's eyes, just like us. Sex appears to play a crucial role in social bonding. A utopic society, no? The fighting occurs instead at the level of the sperm. Just like in humans, bonobo sperm fight it out for the finish line. This is where the competition happens in bonobo sexual reproduction.

Our true relatives?

As you may have guessed, the idea here is that the laissez-faire approach to sex in bonobo groups may have once reflected early human communities, and rather than male competition for women, sperm competition may have actually been the only competition. Such features of human anatomy shared with bonobos include male and female size difference (we are basically the same, unlike in more competitive species like the gorilla), the size of the human testicle (way larger, with more sperm production that seems rational if one man and one woman are paired for life), and the amazing sounds a woman makes when she's on the end of some good lovin' (suggested to be the call for more sex from more men, as it is for the bonobo female) are all examples of our multi-sex partner past. And to be honest, that's just the start. The evidence here is certainly as convincing as any evidence you'll see in opposition of the idea of multi-partner sexual relationships.

Looking outside the bonobo, and in more modern times, we can see that many hunter-gatherers share common sexual practices with our vigorous cousins. Consider communities that believe in partible paternity, the idea that a fetus is comprised of all the sperm of all the men a woman sleeps with. The women believe that the baby will share the traits of those men, and so will sleep with all the men who have traits she might want in the child. The argument suggests that our modern attitude was inculcated by the agricultural revolution. The ability to grow more food lessened the need to share. In fact, more food meant more people. More people meant more likelihood that the food would run out. Which lead to stealing, which lead to hoarding and protecting food and resources. In this way, women (and their babies) became yet another resource to be protected. Who else to pass this newfound property to? I simplify here for brevity, but the importance of the agricultural revolution in (at a minimum) exacerbating our tendency to covet power and protect property is undeniable. The proponents of our new theory of human sexual relationships suggest that we adapted to this new, monogamous way of life as we have to every social change that has characterised our history (consider the cultural variations between ancient societies like the Greeks, the Romans, and the Ottomans). As a result, our scientific approaches are fundamentally biased toward finding evidence to support monogamy and dismiss that which opposes it.

Tie it together

This approach certainly helps explain many of the problems that abound in modern relationships. The prevalence of infidelity, for one. The dissipation of sexual intimacy that is so common in many marriages too, can be explained in this way. If we consider that men and women were never meant to exclusively pair off, we might imagine that such lustful desires would disperse without more men and women in our lives. And most alluringly, consider this approach as a solution for the question of sexual preference. If sex was not solely about reproduction, but instead played a key role in social bonding, what does it matter who one has sex with? All of a sudden, homosexuality, bisexuality, and pansexuality, to name a few, seem far more evolutionarily reasonable. It is interesting to note that even Dr Buss and colleagues' evolutionary research supports the claims to some extent. Consider the fact that despite the seemingly cut-and-dried sexual strategies preferred by men and women, both genders most prefer the same three traits in their partners; trust, intelligence, and warmth. None of which particularly support the pragmatic, and resource focused sexual strategies theory. Consider too the role of attachment. We know that the relationships we have with our parents significantly influence what we seek in our partners. If it's all about the end result (ensuring our babies live on), then why would the social bond we have matter so much? The opposing views on sexual strategy and the role of attachment are becoming a serious point of debate in the literature, and this new perspective does much to close the gap.


It is certainly true to say that sex in the modern day is much harder than the movies would have us believe. No one who's been in a relationship for any significant amount of time would boast that it's easy. Anyone who's played around under the sheets would know that only rarely does it seem like magic, and we're often left disappointed. The approach proposed by Ryan very satisfyingly explains many of the pathologies and so-called 'aberrant' behaviours that plague modern day relationships. But that isn't to say that other approaches have no merit. There are no intransigent opposites, except in the hearts of men and I would suggest a more moderate view. What we can conclude is that sex and love are far more fluid than we've been led to believe and it is blindingly obvious that our current social norms don't always meet our needs. Regardless of which perspective tickles your fancy, you'll save yourself a great deal of heartache by being true to yourself and open with your partners. And most importantly, like Rihanna always says, don't let the bastards get you down (it really does make for a better weekend).

While we're on the topic of evolutionary theory and sex, why not learn three random things that can make you more attractive? Evolutionary theory isn't the only theory though, nor is it the most important. Learn about the seven major approaches to relationship psychology, and how you can use each to hack your relationships. Turning scholarship into wisdom without the usual noise and clutter, we dig up the dirt on psychological theories you can use. Become an armchair psychologist at The Dirt Psychology.

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