The Rise and Fall of the Third Chimpanzee

by Jared Diamond

  The competing units also vary greatly among animal species. In most songbirds, such as American or European robins, individual males or else male/female pairs face off. Among lions and common chimpanzees, small groups of males who may be brothers fight, sometimes to the death. Packs of wolves or hyenas do battle, while ant colonies engage in large-scale wars with other colonies. Although for some species these contests may end in deaths, there is no animal species whose survival as a species is even remotely threatened by such deaths.

  Humans compete with each other for territory as do members of most animal species. Because we live in groups, much of our competition has taken the form of wars between adjacent groups, on the model of the wars between ant colonies rather than the small-scale contests between robins. As with adjacent groups of wolves and common chimps, relations of adjacent human tribes were traditionally marked by xenophobic hostility, intermittently relaxed to permit exchanges of mates (and, in our species, of goods as well). Xenophobia comes especially naturally to our species, because so much of our behaviour is culturally rather than genetically specified, and because cultural differences among human populations are so marked. Those features make it easy for us, unlike wolves and chimps, to recognize members of other groups at a glance by their clothes or hair style.

  What makes human xenophobia much more lethal than chimp xenophobia is of course our recent development of weapons for mass killing at a distance. While Jane Goodall described males of one group of common chimps gradually killing off individuals of the neighbouring group and usurping their territory, those chimps had no means to kill chimps of a more remote group, nor to exterminate all chimps (including themselves). Thus, xenophobic murder has innumerable animal precursors, but only we have developed it to the point of threatening to bring about our fall as a species. Threatening our own existence has now joined art and language as a human hallmark. Hence Chapter Sixteen will survey the history of human genocide, to make clear the ugly tradition from which Dachau’s ovens and modern nuclear warfare spring.

  THIRTEEN

  THE LAST FIRST CONTACTS

  For most of human history, human populations lived in a state of xenophobic isolation from each other, tempered by the need for trade and for exchanging spouses, but reinforced by differences in language and culture. In the modern world, ‘first contacts’ of isolated populations by outsiders have been accelerating, to the point where the last first contact is expected within the present decade. The end of our mutual isolation is bringing a tragic loss in our cultural diversity. Yet it also brings the hope that we may not continue destroying each other with increasingly powerful weapons.

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  ON 4 AUGUST 1938, an exploratory biological expedition from the American Museum of Natural History made a discovery that hastened towards its end a long phase of human history. That was the date on which the advance patrol of the Third Archbold Expedition (named after its leader, Richard Archbold) became the first outsiders to enter the Grand Valley of the Balim River, in the supposedly uninhabited interior of western New Guinea. To everyone’s astonishment, the Grand Valley proved to be densely populated – by 50,000 Papuans, living in the Stone Age, previously unknown to the rest of humanity and themselves unaware of others’ existence. In search of undiscovered birds and mammals, Archbold had found an undiscovered human society.

  To appreciate the significance of Archbold’s finding, we need to understand the phenomenon of ‘first contact’. As I mentioned on here, most animal species occupy a geographic range confined to a small fraction of the Earth’s surface. Of those species occurring on several continents (such as lions and grizzly bears), it is not the case that individuals from one continent visit one another. Instead, each continent, and usually each small part of a continent, has its own distinctive population, in contact with close neighbours but not with distant members of the same species. (Migratory songbirds constitute an apparently glaring exception. But while they do commute seasonally between continents, it is only along a traditional path, and both the summer breeding range and the winter non-breeding range of a given population tend to be quite circumscribed.)

  This geographic fidelity of animals is reflected in the geographic variability that I discussed in Chapter Six. Populations of the same species in different geographic areas tend to evolve into different-looking subspecies, because most breeding remains within the same population. For example, no gorilla of the East African lowland subspecies has ever turned up in West Africa or vice versa, though the eastern and western subspecies look sufficiently different that biologists could recognize a wanderer if there were any.

  In these respects, we humans have been typical animals throughout most of our evolutionary history. Like other animals, each human population is genetically moulded to its area’s climate and diseases, but human populations are also impeded from freely mixing by linguistic and cultural barriers far stronger than in other animals. As mentioned in Chapter Six, an anthropologist can identify roughly where a person originates from the person’s naked appearance, and a linguist or student of dress styles can pinpoint origins much more closely. That is testimony to how sedentary human populations have been.

  While we think of ourselves as travellers, we were quite the opposite throughout several million years of human evolution. Every human group was ignorant of the world beyond its own lands and those of its immediate neighbours. Only in recent millenia did changes in political organization and technology permit some people routinely to travel afar, to encounter distant peoples, and to learn first-hand about places and peoples that they had not personally visited. This process accelerated with Columbus’s voyage of 1492, until today there remain only a few tribes in New Guinea and South America still awaiting first contact with remote outsiders. The Archbold Expedition’s entry into the Grand Valley will be remembered as one of the last first contacts of a large human population. It was thus a landmark in the process by which humanity became transformed from thousands of tiny societies, collectively occupying only a fraction of the globe, to world conquerors with world knowledge.

  How could such a numerous people as the Grand Valley’s 50,000 Papuans remain completely unknown to outsiders until 1938? How could those Papuans in turn remain completely ignorant of the outside world? How did first contact change human societies? I shall argue that this world before first contact – a world that is finally ending within our own generation – holds a key to the origins of human cultural diversity. As world conquerors, our species now numbers over five billion, compared to the mere ten million people who existed before the advent of agriculture. Ironically, though, our cultural diversity has plunged even as our numbers have soared.

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  To anyone who has not been to New Guinea, the long concealment of 50,000 people there seems incomprehensible. After all, the Grand Valley lies only 115 miles from both New Guinea’s north coast and its south coast. Europeans discovered New Guinea in 1526, Dutch missionaries took up residence in 1852, and European colonial governments were established in 1884. Why did it take another fifty-four years to find the Grand Valley?

  The answers – terrain, food, and porters – become obvious as soon as one sets foot in New Guinea and tries to walk away from an established trail. Swamps in the lowlands, endless series of knife-edge ridges in the mountains, and jungle that covers everything reduce one’s progress to a few miles per day under the best conditions. On my 1983 expedition into the Kumawa Mountains, it took me and a team of twelve New Guineans two weeks to penetrate seven miles inland. Yet we had it easy compared to the British Ornithologists’ Union Jubilee Expedition. On 4 January 1910 they landed on New Guinea’s coast and set off for the snow-capped mountains that they could see only a hundred miles inland. On 12 February 1911 they finally gave up and turned back, having covered less than half the distance (forty-five miles) in those thirteen months.

  Compounding those terrain problems is the impossibility of living off the land, because of New Guinea’s lack of big game an
imals. In lowland jungle the staple of New Guineans is a tree called the sago palm, whose pith yields a substance with the consistency of rubber and the flavour of vomit. However, not even New Guineans can find enough wild foods to survive in the mountains. This problem was illustrated by a horrible sight on which the British explorer Alexander Wollaston stumbled while descending a New Guinea jungle trail: the bodies of thirty recently dead New Guineans and two dying children, who had starved while trying to return from the lowlands to their mountain gardens without carrying enough provisions.

  The paucity of wild foods in the jungle compels explorers going through uninhabited areas, or unable to count on obtaining food from native gardens, to bring their own rations. A porter can carry forty pounds, the weight of the food necessary to feed himself for about fourteen days. Thus, until the advent of planes made airdrops possible, all New Guinea expeditions that penetrated more than seven days’ walk from the coast (fourteen days’ round trip) did so by having teams of porters going back and forth, building up food depots inland. Here is a typical plan: fifty porters start from the coast with 700 man-days of food, deposit 200 man-days’ food five days inland, and return in another five days to the coast, having consumed the remaining 500 man-days’ food (fifty men times ten days) in the process. Then fifteen porters march to that first depot, pick up the cached 200 man-days’ food, deposit fifty man-days’ food a further five days’ march inland, and return to the first depot (reprovisioned in the meantime), having consumed the remaining 150 man-days’ food in the process. Then… .

  The expedition that came closest to discovering the Grand Valley before Archbold, the 1921–22 Kremer Expedition, used 800 porters, 200 tons of food, and ten months of relaying to get four explorers inland to just beyond the Grand Valley. Unfortunately for Kremer, his route happened to pass a few miles west of the valley, whose existence he did not suspect because of intervening ridges and jungle.

  Apart from these physical difficulties, the interior of New Guinea seemed to hold no attractions for missionaries or colonial governments, because it was believed to be virtually uninhabited. European explorers landing on the coast or rivers discovered many tribes in the lowlands living off sago and fish, but few people eking out an existence in the steep foothills. From either the north or south coast, the snow-capped Central Cordillera that forms New Guinea’s backbone presents steep faces. It was assumed that the northern and southern faces meet in a ridge. What remained invisible from the coasts was the existence of broad intermontane valleys, hidden behind those faces and suitable for agriculture.

  For eastern New Guinea, the myth of an empty interior was shattered on 26 May 1930, when two Australian miners, Michael Leahy and Michael Dwyer, scaled the crest of the Bismarck Mountains in search of gold, looked down at night on the valley beyond, and were alarmed to see countless dots of light: the cooking fires of thousands of people. For western New Guinea, the myth ended with Archbold’s second survey flight on 23 June 1938. After hours of flying over jungle with few signs of humans, Archbold was astonished to spot the Grand Valley, looking like Holland: a cleared landscape devoid of jungle, neatly divided into small fields outlined by irrigation ditches, and with scattered hamlets. It took six more weeks before Archbold could establish camps at the nearest lake and river where his seaplane could land, and before patrols from those camps could reach the Grand Valley to make first contact with its inhabitants.

  *

  That is why the outside world did not know of the Grand Valley till 1938. Why did the valley’s inhabitants, now referred to as the Dani people, not know of the outside world?

  Part of the reason, of course, is the same logistic problems that faced the Kremer Expedition on its march inland, but in reverse. Yet those problems would be minor in areas of the world with gentler terrain and more wild foods than New Guinea, and they do not explain why all other human societies in the world also used to live in relative isolation. Instead, at this point we have to remind ourselves of a modern perspective that we take for granted. Our perspective did not apply to New Guinea until very recently, and it did not apply anywhere in the world 10,000 years ago.

  Recall that the whole globe is now divided into political states, whose citizens enjoy more or less freedom to travel within the boundaries of their state and to visit other states. Anyone with the time, money, and desire can visit almost any country except for a few xenophobic exceptions, such as Albania and North Korea. As a result, people and goods have diffused around the globe, and many items such as Coca-cola are now available on every continent. I recall with embarrassment my visit in 1976 to a Pacific island called Rennell, whose isolated location, vertical sea cliffs without beaches, and fissured coral landscape had preserved its Polynesian culture unchanged until recently. Setting out at dawn from the coast, I plodded through jungle with not a trace of humans. When in the late afternoon I finally heard a woman’s voice ahead and glimpsed a small hut, my head whirled with fantasies of the beautiful, unspoilt, grass-skirted, bare-breasted Polynesian maiden who awaited me at this remote site on this remote island. It was bad enough that the lady proved to be fat and with her husband. What humiliated my self-image as intrepid explorer was the ‘University of Wisconsin’ sweatshirt that she wore.

  In contrast, for all but the last 10,000 years of human history, unfettered travel was impossible, and diffusion of sweatshirts was very limited. Each village or band constituted a political unit, living in a perpetually shifting state of wars, truces, alliances, and trade with neighbouring groups. New Guinea highlanders spent their entire lives within twenty miles of their birthplace. They might occasionally enter lands bordering their village lands by stealth during a war raid, or by permission during a truce, but they had no social framework for travel beyond immediately neighbouring lands. The notion of tolerating unrelated strangers was as unthinkable as the notion that any such stranger would dare appear.

  Even today, the legacy of this no-trespassing mentality persists in many parts of the world. Whenever I go bird-watching in New Guinea, I take pains to stop at the nearest village to request permission to bird-watch on that village’s land or rivers. On two occasions when I neglected that precaution (or asked permission at the wrong village) and proceeded to boat up the river, I found the river barred on my return by canoes of stone-throwing villagers, furious that I had violated their territory. When I was living among Elopi tribespeople in western New Guinea and wanted to cross the territory of the neighbouring Fayu tribe to reach a nearby mountain, the Elopis explained to me matter-of-factly that the Fayus would kill me if I tried. From a New Guinean perspective, it seemed perfectly natural and self-explanatory. Of course the Fayus will kill any trespasser; you surely do not think they are so stupid that they would admit strangers to their territory? Strangers would just hunt their game animals, molest their women, introduce diseases, and reconnoitre the terrain in order to stage a raid later.

  While most pre-contact peoples had trade relations with their neighbours, many thought they were the only humans in existence. Perhaps the smoke of fires on the horizon, or an empty canoe floating past down a river, did prove the existence of other people. But to venture out of one’s territory to meet those humans, even if they lived only a few miles away, was equivalent to suicide. As one New Guinea highlander recalled his life before first arrival of whites in 1930, ‘We had not seen far places. We knew only this side of the mountains. And we thought that we were the only living people.’

  Such isolation bred great genetic diversity. Each valley in New Guinea has not only its own language and culture, but also its own genetic abnormalities and local diseases. The first valley where I worked was the home of the Foré people, famous to science for their unique affliction with a fatal viral disease called kuru or laughing sickness, which accounted for over half of all deaths (especially among women) and left men outnumbering women three-to-one in some Foré villages. At Karimui, sixty miles to the west of the Foré area, kuru is completely unknown, and the people are ins
tead affected with the world’s highest incidence of leprosy. Still other tribes are unique in their high frequency of deaf mutes, or of male pseudo-hermaphrodites lacking a penis, or of premature aging, or of delayed puberty.

  Today we can picture areas of the globe that we have not visited, from films and television. We can read about them in books. English dictionaries exist for all the world’s major languages, and most villages speaking minor languages contain individuals who have learned one of the world’s major languages. For example, missionary linguists have studied literally hundreds of New Guinea and South American Indian languages in recent decades, and I have found some inhabitant speaking either Indonesian or Neo-Melanesian in every New Guinea village that I have visited, no matter how remote. Linguistic barriers no longer impede the worldwide flow of information. Almost every village in the world today has thereby obtained fairly direct accounts of the outside world and has yielded fairly direct accounts of itself.

  In contrast, pre-contact peoples had no way to picture the outside world, or to learn about it directly. Information instead arrived via long chains of languages, with accuracy lost at each step – as in the children’s game called ‘telephone’ or ‘Chinese whispers’, where one child in a circle whispers a message to the next child, who in turn whispers it to her neighbour, until by the time the message is whispered back to the first child its meaning has become changed beyond recognition. As a result, New Guinea highlanders had no concept of the ocean a hundred miles distant, and knew nothing about the white men who had been prowling their coasts for several centuries. When highlanders tried to figure out why the first arriving white men wore trousers and belts, one theory was that the clothes served to conceal an enormously long penis coiled around the waist. Some Dani believed that a neighbouring group of New Guineans munched grass and had their hands joined behind their back.