Stroll into your local Starbucks and you will find yourself part of a cultural experiment on a scale never seen before on this planet. In less than half a century, the coffee chain has grown from a single outlet in Seattle to nearly 20,000 shops in around 60 countries. Each year, its near identical stores serve cups of near identical coffee in near identical cups to hundreds of thousands of people. For the first time in history, your morning cappuccino is the same no matter whether you are sipping it in Tokyo, New York, Bangkok or Buenos Aires.

Of course, it is not just Starbucks. Select any global brand from Coca Cola to Facebook and the chances are you will see or feel their presence in most countries around the world. It is easy to see this homogenization in terms of loss of diversity, identity or the westernization of society. But, the rapid pace of change also raises the more interesting question of why – over our relatively short history - humans have had so many distinct cultures in the first place. And, if diversity is a part of our psychological make-up, how we will fare in a world that is increasingly bringing together people from different cultural backgrounds and traditions?

To get at this question, I argue that we need to understand what I call our unique ‘capacity for culture’. This trait, which I outline in my book Wired for Culture, makes us stand alone amongst all other animals. Put simply, we can pick up where others have left off, not having to re-learn our cultural knowledge each generation, as good ideas build successively upon others that came before them, or are combined with other ideas giving rise to new inventions.

Take the axe as an example. At first we built simple objects like hand axes chipped or “flaked” from larger stones. But these would give way to more sophisticated axes, and when someone had the idea to combine a shaped club with one of these hand axes, the first “hafted axe” was born. Similarly when someone had the idea to stretch a vine between the ends of a bent stick the first bow was born and you can be sure the first arrow soon followed.

Life savers

In more recent history, this ‘cumulative cultural adaptation’ that our capacity for culture grants has been accelerated by the rise of archiving technology. Papyrus scrolls, books and the internet allow us to even more effectively share knowledge with successive generations, opening up an unbridgeable gap in the evolutionary potential between humans and all other animals.

Chimpanzees, for example, are renowned for their “tool use” and we think this is evidence of their intelligence. But you could go away for a million years and upon your return the chimpanzees would still be using the same sticks to ‘fish’ for termites and the same rocks to crack open nuts – their “cultures” do not cumulatively adapt. Rather than picking up where others have left off, they start over every generation. Just think if you had to re-discover how to make fire, tan leather, extract bronze or iron from earth, or build a smartphone from scratch. That is what it is like to be the other animals.

Not so for humans. Around 60,000 years ago, cumulative cultural adaptation was what propelled modern humans out of Africa in small tribal groups, by enabling us to acquire knowledge and produce technologies suitable to different environments. Eventually these tribes would occupy nearly every environment on Earth – from living on ice to surviving in deserts or steaming jungles, even becoming sea-going mariners as the Polynesians did. And amongst each one we see distinct sets of beliefs, customs, language and religion.

The importance of the tribe in our evolutionary history has meant that natural selection has favoured in us a suite of psychological dispositions for making our cultures work and for defending them against competitors. These traits include cooperation, seeking affiliations, a predilection to coordinating our activities, and tendencies to trade and exchange goods and services. Thus, we have taken cooperation and sociality beyond the good relations among family members that dominate the rest of the animal kingdom, to making cooperation work among wider groups of people.

In fact, we have evolved a set of dispositions that allow us to treat other members of our tribe or society as “honorary relatives”, thereby unlocking a range of emotions that we would normally reserve for other family members. A good example of this so-called cultural nepotism is the visceral feeling you have when one of your nation’s soldiers is lost in battle – just compare that feeling to how you react to the news of a similar loss of a soldier from another nation. We also see our cultural nepotism in the dispositions we have to hold doors for people, give up our seats on trains, or contribute to charities, and we might even risk our lives jumping into a river to save someone from drowning, or when we fight for our countries in a war.

Of course, this nepotism is not just a positive force. It is also a trait that can be exploited by propagandists and to produce Kamikaze-like or other suicidal behaviors. But the success of cooperation as a strategy has seen our species for at least the last 10,000 years on a long evolutionary trajectory towards living in larger and larger social groupings that bring together people from different tribal origins. The economies of scale that we realize even in a small grouping ‘scale up’ in larger groups, so much so that larger groups can often afford to have armies, to build defensive walls around their settlements. Large groups also benefit from the efficiencies that flow from a division of labour, and from access to a vast shared store of information, skills, technology and good luck.

‘One world’

And so in a surprising turn, the very psychology that allows us to form and cooperate in small tribal groups, makes it possible for us to form into the larger social groupings of the modern world. Thus, early in our history most of us lived in small bands of maybe 50 to 200 people. At some point tribes formed that were essentially coalitions or bands of bands. Collections of tribes later formed into chiefdoms in which for the first time in our history a single ruler emerged.

Eventually several chiefdoms would come together in nascent city-states such as Catal-Huyuk in present day Turkey or Jericho in the Palestinian West-Bank, both around 10,000 years old. City-states gave way to nations states, and eventually to collections of states such as the United Kingdom or the United States, and even in our modern world to collections of nations such as seen in the European Union. At each step formerly competing entities discovered that cooperation could return better outcomes than endless cycles of betrayal and revenge.

This is not to say that cooperation is easy, or that it is never subject to reversals. Just look at the outpouring of cultural diversity that sprang up with the collapse of the Soviet Union. Despite being suppressed for decades, almost overnight Turkmenistan, Uzbekistan, Kazakhstan, Chechnya, Tajikistan, Moldova, Kyrgyzstan, and Dagestan reappeared, all differentiated by culture, ethnicity, and language.

So how will these two competing tendencies that comprise our evolved tribal psychology – one an ancient disposition to produce lots of different cultures, the other an ability to extend honorary relative status to others even in large groupings – play out in our modern, interconnected and globalised world? There is in principle no reason to rule out a “one world” culture, and in some respects, as Starbucks vividly illustrates, we are already well on the way.

Thus, it seems our tribal psychology can extend to groups of seemingly nearly any size. In large countries such as the United Kingdom, Japan, the United States, Brazil, India and China hundreds of millions and even over a billion people can all be united around a single tribal identity as British or Japanese, American, Indian or Chinese and they will have a tendency to direct their cultural nepotism towards these other members of their now highly extended tribe. If you take this behaviour for granted, just imagine 100,000 dogs or hyenas packed into a sporting arena – not a pretty sight.

‘Bumpy road’

But two factors looming on the horizon are likely to slow the rate at which cultural unification will happen. One is resources, the other is demography. Cooperation has worked throughout history because large collections of people have been able to use resources more effectively and provide greater prosperity and protection than smaller groups. But that could change as resources become scarce.

This must be one of the most pressing social questions we can ask because if people begin to think they have reached what we might call ‘peak standard of living’ then they will naturally become more self-interested as the returns from cooperation begin to leak away. After all, why cooperate when there are no spoils to divide?

Related to this, the dominant demographic trend of the next century will be the movement of people from poorer to richer regions of the world. Diverse people will be brought together who have little common cultural identity of the sort that historically has prompted our cultural nepotism, and this will happen at rates that exceed those at which they can be culturally integrated.

At first, I believe, these factors will cause people to pull back from whatever level of cultural ‘scaling’ they have achieved to the previous level. An example is the nations of the European Union squabbling over national versus EU rights and privileges. A more troubling example might be the rise of nationalist groups and political parties, such as Marine le Pen’s Front National in France, or similar far right groups in Britain and several European nations.

Then, if the success of modern societies up to this point is anything to go by, new and ever more heterogeneous and resource-scarce societies will increasingly depend upon clear enforcement of cultural or democratically derived rules to maintain stability, and will creak under the strain of smaller social groupings seeking to disengage further from the whole.

One early harbinger of a sense of decline in the sense of ‘social relatedness’ might be the increasing tendencies of people to avoid risk, to expect safety, to be vigilant about fairness, to require and to be granted “rights.” These might all be symptoms of a greater sense of self-interest, brought about perhaps by declines in the average amount of “togetherness” we feel. When this happens, we naturally turn inwards, effectively reverting to our earlier evolutionary instincts, to a time when we relied on kin selection or cooperation among families for our needs to be met.

Against this backdrop the seemingly unstoppable and ever accelerating cultural homogenization around the world brought about by travel, the internet and social networking, although often decried, is probably a good thing even if it means the loss of cultural diversity: it increases our sense of togetherness via the sense of a shared culture. In fact, breaking down of cultural barriers – unfashionable as this can sound – is probably one of the few things that societies can do to increase harmony among ever more heterogeneous peoples.

So, to my mind, there is little doubt that the next century is going to be a time of great uncertainty and upheaval as resources, money and space become ever more scarce. It is going to be a bumpy road with many setbacks and conflicts. But if there was ever a species that could tackle these challenges it is our own. It might be surprising, but our genes, in the form of our capacity for culture, have created in us a machine capable of greater cooperation, inventiveness and common good than any other on Earth. And of course it means you can always find a cappuccino just the way you like it no matter where we wake up.

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