Wired for Culture: Origins of the Human Social Mind (8 page)

But why do we behave this way? Could it be that our cultural survival vehicles have evolved tendencies to protect the knowledge and wisdom to which they owe their success?

CULTURES CARVE UP THE LANDSCAPE—LINGUISTICALLY

A WALK
along the northeast coast of Papua New Guinea will bring you into contact every five to ten miles with a tribe speaking a different language: in that part of New Guinea you could encounter Korak speakers, quickly followed along the coast by Brem speakers, who in turn are followed by Wanambre speakers, and none of these more than ten miles apart. Each of these tribes is a distinct group of people, making their living alongside each other in the dense forests of that island, and speaking mutually unintelligible languages. If we were to encounter this diversity of languages inside an area of a typical medium-sized town, we might expect to find not just three or more different languages spoken, but three or more distinct groups of people, brought up speaking a different language and living separate lives, each having carved out a portion of the town to live in!

The density of languages in Papua New Guinea strains credulity, but recall how the Papuan man asked if it could be true that the societies which spoke these different languages were this tightly packed together replied, “Oh no, they are far closer together than that.” And it is true, an astonishing figure of over 800 different languages, or about 15 percent of all languages found on Earth, are spoken in the mere 312,000 square miles of the island of New Guinea—with many having only a few thousand speakers. This is an area slightly bigger than the state of Texas. Languages are even more tightly packed in the tiny Polynesian island archipelago of Vanuatu, northwest of Australia. Vanuatu’s islands cover just 4,100 square miles, and yet over 100 distinct languages are spoken on them, each one by an average of just 2,000 speakers. Even this gives a more sedate picture than becomes apparent when one is on the ground in these regions. For instance, the Vanuatu island of Gora covers 132 square miles, and like so many of the islands in this region, it is the roughly circular remnant plug of an ancient volcano. Gora is just twelve to thirteen miles in diameter, but this speck of an island supports five languages—Lakon or Vuré, Olrat, Koro, Dorig, and Nume. This is a density of languages about tenfold higher than that of Papua New Guinea.

Language is one of our defining traits as a species, but we are probably the only animal in which two of its individuals plucked from different places—even right next door—might not be able to communicate with one another, almost as if they were two different biological species. Sometimes, even speakers of the same language can confuse one another: a young English boy I know, travelling in America, was told by someone who overheard him speaking, “I can tell from your accent that you’re from somewhere in Europe.” By comparison to our linguistic isolation, you could take a gorilla from its troop and put it in any other troop anywhere gorillas are found, and it would know what to do. There would probably be some fighting over territory, and attempts at establishing who is dominant over whom, but for the most part life would be routine. The new gorilla would communicate as all gorillas communicate, fight as gorillas fight, make the same kinds of nest, and eat the same kinds of food. There is nothing special about gorillas. This experiment could be repeated with donkeys, or ducks, or goldfish, or frogs, and get much the same outcome.

So, why is it that groups of people in New Guinea, or more generally just about anywhere in the tropics, all more or less living the same lifestyle, divide up their territories so exclusively as to evolve different languages, and sometimes every few miles? What makes this division even more peculiar is that, where different biological species specialize at exploiting different features of the environment—what biologists describe as a species’
niche
—in any given area the humans are all occupying more or less the same niche, save for one: human societies seem to have a disposition to acquire their own linguistic niche and then maintain it. The anthropologist Don Kulick describes how

New Guinean communities have purposely fostered linguistic diversity because they have seen language as a highly salient marker of group identity… [they] have cultivated linguistic differences as a way of “exaggerating” themselves in relation to their neighbors… . One community [of Buian language speakers], for instance, switched all its masculine and feminine gender agreements, so that its language’s gender markings were the exact opposite of those of the dialects of the same language spoken in neighboring villages; other communities replaced old words with new ones in order to “be different” from their neighbors’ dialects.

Kulick also relates an account from another linguist of a New Guinean village of Selepet speakers. One day, the community met and collectively decided to change their word for “no” from
bia
to
bune
. The reason they gave was that they wanted to be distinct from other Selepet speakers in a neighboring village, and with immediate effect. They have spoken differently ever since. We can only sympathize with the confusion someone would have felt who had gone away hunting for a few days.

There is speculation that humans might be innately programmed to recognize and prefer people who share our language, or that if not innate, the preferences arise very early in life, even before we can speak. By five to six months, infants prefer to look at people whom they have heard speaking their native language. Katherine Kinzler and her colleagues note that

Older infants preferentially accept toys from native-language speakers, and preschool children preferentially select native-language speakers as friends. Variations in accent are sufficient to evoke these social preferences, which are observed in infants before they produce or comprehend speech and are exhibited by children even when they comprehend the foreign-accented speech. Early-developing preferences for native-language speakers may serve as a foundation for later-developing preferences and conflicts among social groups.

Neighboring communities also of course distinguish themselves in customs, beliefs, art, dance, weaponry, costumes, singing, music, and architecture. For instance, among the nomadic pastoralists of Northern Kenya, the Gabbra people dress simply in muted colors, while their next-door neighbors the Samburu wear vivid red robes, and the nearby Turkana favor dark colors and, among the women, copious amounts of metal jewelry and neck rings that can give them a daunting appearance.

It is a pattern seen all over the world. In the first years of the nineteenth century, the explorers Meriwether Lewis and William Clark made their long trek from the Missouri River all the way to the west coast of America and then back. The lands they walked through were uncharted, and their diaries show they were struck by the sheer number and variety of the Native American tribes they encountered. Dayton Duncan and Ken Burns, in their account
Lewis and Clark: The Journey of the Corps of Discovery
, write that

the dizzying diversity of Native American life is one of the clearest (though unspoken) images to emerge from [Lewis and Clark’s] journals. The West through which the Corps of Discovery traveled was neither an “uninhabited wilderness” nor a single “Indian world.” Indians thought of themselves as many different people, not as one monolithic group—and understandably so. They were as varied as the western landscape itself… . [Some] roamed the Plains following the buffalo herds, living in tepees that could be moved at a moment’s notice; people who were farmers… lived in permanent villages of rounded earth lodges; people who lived in stick wickiups and dug for roots; people who fished for their food and dwelled in large houses made of wooden planks. Some measured their wealth in horses; others had no horses at all. Some were predominantly tall, or wore forelocks of their hair pushed up as a sign of distinction. Others were shorter, stouter and saw beauty in a forehead flattened by boards.

Lewis and Clark were encountering just a small number of the many different cultural survival vehicles that had evolved in the interior of that vast continent. Prior to the arrival of Europeans, there were over five hundred distinct Native American languages spoken in what is now the territory of Canada and the United States, and these are just the ones that linguists and archaeologists have been able to document.

The human tendency to separate into distinct societies has given human language a geographical mosaic on which to play out its evolution, and we expect new cultures and languages to form naturally as people spread out. The puzzle is that human groups appear to do just the opposite: it is where people are most closely packed together, as in Papua New Guinea or Vanuatu, that the greatest number of different societies is found. A colored-in linguistic map of the tropics looks as though a patchwork quilt has been laid over the landscape. By comparison in the northern regions of North America, there are only a handful of societies, each one occupying a huge area, in the entire west to east expanse of that vast continent. People need to move over large areas in this sparse landscape just to eke out a living, and this tends to blend culture and language as people continually trade, marry, and talk to each other. Remarkably, it is a pattern human societies share with biological species. Where dozens of species of bats, similar numbers of small mice and rat species, and hundreds or thousands of species of insect live in the tropics, the frozen wastelands of the polar regions of North America can only support a handful of different mammal species, such as the caribou, wolf, and polar bear.

Human cultural groups have historically partitioned the landscape among themselves almost as if they were separate biological species. But why speak a different language every few miles? Why not in regions such as the tropics form one giant cooperative society? We seem confronted with the idea that human groups have had an innate tendency throughout history to divide and form into new groups, distinct from others, and just as soon as the environment will allow it. Is it to establish an identity and to protect our knowledge and wisdom from those who might eavesdrop or, worse, subvert our group? If so, it is a risky thing to do because smaller groups are more easily overrun by others, and more vulnerable to bad luck, the loss of key people, and knowledge. But if a group can split off and survive, its members will be able to compete with and maybe even displace other groups looking to use the same lands. The advantage of forming a new group is that now
your
offspring rather than someone else’s come to inherit the lands around you, and they, in turn, can use them to have even more children. Our tendency to form into distinct societies might have its origins in our most basic instincts to promote copies of our genes.

CULTURES RESTRICT THE FLOW OF GENES

EVEN IN
our modern developed world with roads and other links, people can often differ culturally and linguistically over a few tens of miles, as any trip around the shires of England, the French
D
é
partements
or the Swiss Cantons will reveal. These differences tell us that we are a species with a long-term history of staying put, or at least of not moving very far. It is easy to dismiss this as a simple consequence of a lack of mobility; but why does that lack of mobility exist? We must remember that we are the species that occupied the world, and we managed to do so before trains, motorbikes, cars, wagons, roads, or even footpaths were invented. So, our apparent lack of mobility really tells us that, historically anyway, once we get to a place we have tended to stay there, and maybe even slow the pace of others seeking to move in.

There is an ancient moor about five miles north of the city of Oxford in England, called Otmoor. The narrow road that winds around the roughly circular moor is about fourteen miles long and runs through seven villages, all of which date back more than 1,000 years, into Anglo-Saxon times: Oddington, Charlton-on-Otmoor, Fencott, Murcott, Horton-cum-Studley, Beckley, and Noke. In the 1960s, the biological anthropologist Geoffrey Harrison, working at Oxford University, became aware that the seven villages had kept detailed parish records of births, deaths, and marriages dating back at least four hundred years. Harrison and his colleagues realized that they could use these records to track the movement of people among the villages. They quickly established that there was very little mobility and that marriage was one of the few ways by which people moved to a different place on the moor. But the bigger surprise was that prior to the eighteenth century, people often did not venture any further than the neighboring village in their search for someone to marry. In fact, because there was no route directly across the swampy moor, people had been moving from village to village around it in a circular pattern for centuries.

This surprising lack of mobility is not a phenomenon confined to small villages in a rural part of England. Walking through New York City’s Little Italy and Chinatown in Manhattan, it is easy to stand in the middle of the street that divides these two communities and hear Italian spoken by third- or fourth-generation descendants of Italian immigrants on one side and Chinese spoken by third- or fourth-generation descendants of Chinese immigrants on the other. If cultures throughout our history have tended to keep to themselves, avoid each other, or even erect barriers, such as the geographical patterns might suggest, then this should be seen in our genes. Anyone can spot genetic differences between the Chinese and Italian groups, but there are more subtle differences even among people who otherwise “look” the same.

Some years ago the statistician Robert Sokal measured a large number of background genetic markers in samples of people from all over Europe. These markers do not influence how we look or feel or what we are like. They are called
neutral markers
, and they merely identify people who have been separated for some time. Sokal applied a method called
wombling
(named after the statistician W. H. Womble) to measure the rate of change in genetic markers between these different locations. If people gradually diffuse over an area such as Europe, then no boundaries of abrupt genetic difference are expected. But Sokal discovered thirty-three boundaries in Europe that separated areas of especially sharp differences in the genetic markers. Not surprisingly, most corresponded to physical barriers such as the Alps or the English Channel. But for eleven of them, there was no physical or political barrier to the movement of people. Instead, in nine of these eleven places it was language differences that kept people from mixing. It seems humans prefer to have sex with people they can talk to!