I first published this article in The Conversation on 31 May 2011. It highlights some of the arguments about marriage in Chapter 6 of Sex, Genes & Rock ‘n’ Roll
It’s the sort of news conservative politicians and commentators latch on to as a sure-fire sign that the end of civilisation is nigh: marriage rates are in continuing decline. But is this really such a bad thing?
Marriage rates in the developed world have been falling for decades. In the the latest reiteration of this trend, the New York Times reported last week that fewer than half of US households now comprise married couples, down from 78% in the 1950s.
Social conservatives have long coddled a sweet nostalgia for the 1950s as the golden age of matrimony. This yearning usually accompanies confident claims that long-term monogamy is the only natural mating pattern for humans.
But just what is the “natural” human mating system?
Christopher Ryan and Cacilda Jethá, authors of Sex at Dawn, conclude that while people fall deeply in love and form wonderfully strong pair bonds, they also relish plenty of sexual variety.
Ryan and Jethá’s examination of data on mating patterns in traditional foraging societies – from the Curripaco people of Brazil to the Iroquois who lived in upstate New York until the 18th century – suggests that our ancestors spent most of evolutionary history behaving promiscuously, with occasional short-term relationships lasting months rather than years.
My own reading of the research leads me to infer that individuals have the capacity for almost infinite variety in their sexual behaviour, from rampant promiscuity to life-long monogamy.
Humans have evolved to make the best of the circumstances into which they are born. There are better ways to approach this type of behaviour than pontificating that one way of life is somehow “superior” to all others. We can learn much about relationships and happiness by understanding how economics interacts with our evolved behaviour to shape what individuals do under particular circumstances.
Cooperative conflicts
In recent decades both economists and evolutionary biologists have come to realise mothers and fathers walk a perpetual tightrope between cooperation and conflict. Even when two people love each other intensely, there’s often an inherent conflict between their interests.
For example, parents often have differing opinions on whether to have another child. Mothers, who bear the physical cost of carrying the baby to term and then breastfeeding, can be far more reluctant to have another child than their partners.
Conflicts can also arise when it comes to spending patterns. Mothers are almost universally more likely to spend what income they have on the family than fathers.
Fathers, by contrast, are more likely to buy luxury products that signal status or to spend money on recreation. Even in the poorest countries, fathers are more likely than mothers to spend money they can’t afford on cigarettes, alcohol and fancy clothing.
Understanding these permanently-recurring conflicts can help societies mitigate the damage when love or lust goes awry.
We can achieve so much more when we understand two key points:
1) Conflict colours even our most loving and apparently-harmonious relationships.
2) Partners can be in cooperative agreement and simultaneously have conflicting agendas.
The economic understanding of cooperative conflicts has quite literally changed the world. Development agencies now know the most effective way to cure poverty and to improve the lives of families and communities is to educate and empower women, particularly mothers.
Working hard or hardly working?
So, is conflict the biggest problem for marriages? Well, no.
Across all human societies, the biggest predictor of how long marriages will last is how hard the men in those societies tend to work.
In societies where living is comparatively easy, fathers tend to do very little around the home – preferring to hang out and play games with other men. In such societies, marriages don’t tend to last as long.
It may seem obvious, but teamwork really matters.
The Inuit of the Arctic illustrate this perfectly. Men hunt seals, whales and caribou to provide almost all the food and raw material for tools and clothes. Women butcher the prey, prepare the food, render oil for heating and lighting and make clothes. Only by working as a team can Inuit families survive in the most extreme environment people currently inhabit.
In tropical environments, including certain parts of the Amazon (where food grows fast,there are plenty of animals to hunt and living is generally easier), marriages tend to last just long enough for the woman to make it through the critical period of pregnancy and breastfeeding, during which she depends on the man’s help. Among the Aché of the Amazon, the average woman marries ten different times before menopause.
Good times equal short marriages
We tend to think short-lived celebrity marriages are a symptom of fatuous hedonism. Perhaps, instead, they are a side-effect of being freed from the financial and time constraints that force mere mortals to buckle down and cooperate (even in the face of ever-present conflict) with their partners.
Plummeting marriage rates in Western societies have many causes, but one of them just might be an improvement in living standards.
Wealthy, educated people are far less likely to marry in societies such as the USA and Australia than in developing parts of the world.
Despite the conservative tendency to be gloomy about modern times and to wax nostalgic about bygone decades, living standards have improved dramatically and poverty has waned for most of the past century.
If marriage rates tumble as a consequence, well, so be it.
