Collapse

by Diamond, Jared

  In the remainder of this book we shall be considering environmental problems, similar to Montana’s, in various past and modern societies. For the past societies that I shall discuss, half of which lack writing, we know far less about individual people’s values and goals than we do for Montana. For the modern societies, information about values and goals is available, but I myself have more experience of them in Montana than elsewhere in the modern world. Hence as you read this book, and as you consider environmental problems posed mostly in impersonal terms, please think of the problems of those other societies as viewed by individual people like Stan Falkow, Rick Laible, Chip Pigman, Tim Huls, John Cook, and the Hirschy brothers and sisters. When we discuss Easter Island’s apparently homogeneous society in the next chapter, imagine an Easter Island chief, farmer, stone carver, and porpoise fisherman each relating his or her particular life story, values, and goals, just as my Montana friends did for me.

  PART TWO

  PAST SOCIETIES

  CHAPTER 2

  Twilight at Easter

  The quarry’s mysteries ■ Easter’s geography and history ■ People and food ■ Chiefs, clans, and commoners ■ Platforms and statues ■ Carving, transporting, erecting ■ The vanished forest ■ Consequences for society ■ Europeans and explanations ■ Why was Easter fragile? ■ Easter as metaphor ■

  No other site that I have visited made such a ghostly impression on me as Rano Raraku, the quarry on Easter Island where its famous gigantic stone statues were carved (Plate 5). To begin with, the island is the most remote habitable scrap of land in the world. The nearest lands are the coast of Chile 2,300 miles to the east and Polynesia’s Pitcairn Islands 1,300 miles to the west (map, pp. 84-85). When I arrived in 2002 by jet plane from Chile, my flight took more than five hours, all spent over the Pacific Ocean stretching endlessly between the horizons, with nothing to see below us except water. By the time, towards sunset, that the small low speck that was Easter Island finally did become dimly visible ahead in the twilight, I had become concerned whether we would succeed in finding the island before nightfall, and whether our plane had enough fuel to return to Chile if we overshot and missed Easter. It is hardly an island that one would expect to have been discovered and settled by any humans before the large swift European sailing ships of recent centuries.

  Rano Raraku is an approximately circular volcanic crater about 600 yards in diameter, which I entered by a trail rising steeply up to the crater rim from the low plain outside, and then dropping steeply down again toward the marshy lake on the crater floor. No one lives in the vicinity today. Scattered over both the crater’s outer and inner walls are 397 stone statues, representing in a stylized way a long-eared legless human male torso, mostly 15 to 20 feet tall but the largest of them 70 feet tall (taller than the average modern 5-story building), and weighing from 10 up to 270 tons. The remains of a transport road can be discerned passing out of the crater through a notch cut into a low point in its rim, from which three more transport roads about 25 feet wide radiate north, south, and west for up to 9 miles towards Easter’s coasts. Scattered along the roads are 97 more statues, as if abandoned in transport from the quarry. Along the coast and occasionally inland are about 300 stone platforms, a third of them formerly supporting or associated with 393 more statues, all of which until a few decades ago were not erect but thrown down, many of them toppled so as to break them deliberately at the neck.

  From the crater rim, I could see the nearest and largest platform (called Ahu Tongariki), whose 15 toppled statues the archaeologist Claudio Cristino described to me re-erecting in 1994 by means of a crane capable of lifting 55 tons. Even with that modern machinery, the task proved challenging for Claudio, because Ahu Tongariki’s largest statue weighed 88 tons. Yet Easter Island’s prehistoric Polynesian population had owned no cranes, no wheels, no machines, no metal tools, no draft animals, and no means other than human muscle power to transport and raise the statues.

  The statues remaining at the quarry are in all stages of completion. Some are still attached to the bedrock out of which they were being carved, roughed out but with details of the ears or hands missing. Others are finished, detached, and lying on the crater slopes below the niche where they had been carved, and still others had been erected in the crater. The ghostly impression that the quarry made on me came from my sense of being in a factory, all of whose workers had suddenly quit for mysterious reasons, thrown down their tools, and stomped out, leaving each statue in whatever stage it happened to be at the moment. Littering the ground at the quarry are the stone picks, drills, and hammers with which the statues were being carved. Around each statue still attached to rock is the trench in which the carvers stood. Chipped in the rock wall are stone notches on which the carvers may have hung the gourds that served as their water bottles. Some statues in the crater show signs of having been deliberately broken or defaced, as if by rival groups of carvers vandalizing one another’s products. Under one statue was found a human finger bone, possibly the result of carelessness by a member of that statue’s transport crew. Who carved the statues, why did they carve them at such effort, how did the carvers transport and raise such huge stone masses, and why did they eventually throw them all down?

  Easter’s many mysteries were already apparent to its European discoverer, the Dutch explorer Jacob Roggeveen, who spotted the island on Easter Day (April 5, 1722), hence the name that he bestowed and that has remained. As a sailor who had just spent 17 days crossing the Pacific from Chile in three large European ships without any sight of land, Roggeveen asked himself: how had the Polynesians greeting him when he landed on Easter’s coast reached such a remote island? We know now that the voyage to Easter from the nearest Polynesian island to the west would have taken at least as many days. Hence Roggeveen and subsequent European visitors were surprised to find that the islanders’ only watercraft were small and leaky canoes, no more than 10 feet long, capable of holding only one or at most two people. In Roggeveen’s words: “As concerns their vessels, these are bad and frail as regards use, for their canoes are put together with manifold small planks and light inner timbers, which they cleverly stitched together with very fine twisted threads, made from the above-named field-plant. But as they lacked the knowledge and particularly the materials for caulking and making tight the great number of seams of the canoes, these are accordingly very leaky, for which reason they are compelled to spend half the time in bailing.” How could a band of human colonists plus their crops, chickens, and drinking water have survived a two-and-a-half-week sea journey in such watercraft?

  Like all subsequent visitors, including me, Roggeveen was puzzled to understand how the islanders had erected their statues. To quote his journal again, “The stone images at first caused us to be struck with astonishment, because we could not comprehend how it was possible that these people, who are devoid of heavy thick timber for making any machines, as well as strong ropes, nevertheless had been able to erect such images, which were fully 30 feet high and thick in proportion.” No matter what had been the exact method by which the islanders raised the statues, they needed heavy timber and strong ropes made from big trees, as Roggeveen realized. Yet the Easter Island that he viewed was a wasteland with not a single tree or bush over 10 feet tall (Plates 6, 7): “We originally, from a further distance, have considered the said Easter Island as sandy, the reason for that is this, that we counted as sand the withered grass, hay, or other scorched and burnt vegetation, because its wasted appearance could give no other impression than of a singular poverty and barrenness.” What had happened to all the former trees that must have stood there?

  Organizing the carving, transport, and erection of the statues required a complex populous society living in an environment rich enough to support it. The statues’ sheer number and size suggest a population much larger than the estimated one of just a few thousand people encountered by European visitors in the 18th and early 19th centuries: what had happened to the former large popula
tion? Carving, transporting, and erecting statues would have called for many specialized workers: how were they all fed, when the Easter Island seen by Roggeveen had no native land animals larger than insects, and no domestic animals except chickens? A complex society is also implied by the scattered distribution of Easter’s resources, with its stone quarry near the eastern end, the best stone for making tools in the southwest, the best beach for going out fishing in the northwest, and the best farmland in the south. Extracting and redistributing all of those products would have required a system capable of integrating the island’s economy: how could it ever have arisen in that poor barren landscape, and what happened to it?

  All those mysteries have spawned volumes of speculation for almost three centuries. Many Europeans were incredulous that Polynesians, “mere savages,” could have created the statues or the beautifully constructed stone platforms. The Norwegian explorer Thor Heyerdahl, unwilling to attribute such abilities to Polynesians spreading out of Asia across the western Pacific, argued that Easter Island had instead been settled across the eastern Pacific by advanced societies of South American Indians, who in turn must have received civilization across the Atlantic from more advanced societies of the Old World. Heyerdahl’s famous Kon-Tiki expedition and his other raft voyages aimed to prove the feasibility of such prehistoric transoceanic contacts, and to support connections between ancient Egypt’s pyramids, the giant stone architecture of South America’s Inca Empire, and Easter’s giant stone statues. My own interest in Easter was kindled over 40 years ago by reading Heyerdahl’s Kon-Tiki account and his romantic interpretation of Easter’s history; I thought then that nothing could top that interpretation for excitement. Going further, the Swiss writer Erich von Däniken, a believer in visits to Earth by extraterrestrial astronauts, claimed that Easter’s statues were the work of intelligent spacelings who owned ultramodern tools, became stranded on Easter, and were finally rescued.

  The explanation of these mysteries that has now emerged attributes statue-carving to the stone picks and other tools demonstrably littering Rano Raraku rather than to hypothetical space implements, and to Easter’s known Polynesian inhabitants rather than to Incas or Egyptians. This history is as romantic and exciting as postulated visits by Kon-Tiki rafts or extraterrestrials—and much more relevant to events now going on in the modern world. It is also a history well suited to leading off this series of chapters on past societies, because it proves to be the closest approximation that we have to an ecological disaster unfolding in complete isolation.

  Easter is a triangular island consisting entirely of three volcanoes that arose from the sea, in close proximity to each other, at different times within the last million or several million years, and that have been dormant throughout the island’s history of human occupation. The oldest volcano, Poike, erupted about 600,000 years ago (perhaps as much as 3,000,000 years ago) and now forms the triangle’s southeast corner, while the subsequent eruption of Rano Kau formed the southwest corner. Around 200,000 years ago, the eruption of Terevaka, the youngest volcano centered near the triangle’s north corner, released lavas now covering 95% of the island’s surface.

  Easter’s area of 66 square miles and its elevation of 1,670 feet are both modest by Polynesian standards. The island’s topography is mostly gentle, without the deep valleys familiar to visitors to the Hawaiian Islands. Except at the steep-sided craters and cinder cones, I found it possible almost anywhere on Easter to walk safely in a straight line to anywhere else nearby, whereas in Hawaii or the Marquesas such a walking path would have quickly taken me over a cliff.

  The subtropical location at latitude 27 degrees south—approximately as far south of the equator as Miami and Taipei lie north of the equator—gives Easter a mild climate, while its recent volcanic origins give it fertile soils. By themselves, this combination of blessings should have endowed the island with the makings of a miniature paradise, free from the problems besetting much of the rest of the world. Nevertheless, Easter’s geography did pose several challenges to its human colonists. While a subtropical climate is warm by the standards of European and North American winters, it is cool by the standards of mostly tropical Polynesia. All other Polynesian-settled islands except New Zealand, the Chathams, Norfolk, and Rapa lie closer to the equator than does Easter. Hence some tropical crops that are important elsewhere in Polynesia, such as coconuts (introduced to Easter only in modern times), grow poorly on Easter, and the surrounding ocean is too cold for coral reefs that could rise to the surface and their associated fish and shellfish. As Barry Rolett and I found while tramping around on Teravaka and Poike, Easter is a windy place, and that caused problems for ancient farmers and still does today; the wind makes recently introduced breadfruits drop before they are ripe. Easter’s isolation meant, among other things, that it is deficient not just in coral-reef fish but in fish generally, of which it has only 127 species compared to more than a thousand fish species on Fiji. All of those geographic factors resulted in fewer food sources for Easter Islanders than for most other Pacific Islanders.

  The remaining problem associated with Easter’s geography is its rainfall, on the average only about 50 inches per year: seemingly abundant by the standards of Mediterranean Europe and Southern California, but low by Polynesian standards. Compounding the limitations imposed by that modest rainfall, the rain that does fall percolates quickly into Easter’s porous volcanic soils. As a consequence, freshwater supplies are limited: just one intermittent stream on Mt. Teravaka’s slopes, dry at the time of my visit; ponds or marshes at the bottoms of three volcanic craters; wells dug down where the water table is near the surface; and freshwater springs bubbling up on the ocean bottom just offshore or between the high-tide and low-tide lines. Nevertheless, Easter Islanders did succeed in getting enough water for drinking, cooking, and growing crops, but it took effort.

  Both Heyerdahl and von Däniken brushed aside overwhelming evidence that the Easter Islanders were typical Polynesians derived from Asia rather than from the Americas, and that their culture (including even their statues) also grew out of Polynesian culture. Their language was Polynesian, as Captain Cook had already concluded during his brief visit to Easter in 1774, when a Tahitian man accompanying him was able to converse with the Easter Islanders. Specifically, they spoke an eastern Polynesian dialect related to Hawaiian and Marquesan, and most closely related to the dialect known as Early Mangarevan. Their fishhooks, stone adzes, harpoons, coral files, and other tools were typically Polynesian and especially resembled early Marquesan models. Many of their skulls exhibit a characteristically Polynesian feature known as a “rocker jaw.” When DNA extracted from 12 skeletons found buried in Easter’s stone platforms was analyzed, all 12 samples proved to exhibit a nine-base-pair deletion and three base substitutions present in most Polynesians. Two of those three base substitutions do not occur in Native Americans and thus argue against Heyerdahl’s claim that Native Americans contributed to Easter’s gene pool. Easter’s crops were bananas, taro, sweet potato, sugarcane, and paper mulberry, typical Polynesian crops mostly of Southeast Asian origin. Easter’s sole domestic animal, the chicken, was also typically Polynesian and ultimately Asian, as were even the rats that arrived as stowaways in the canoes of the first settlers.

  The prehistoric Polynesian expansion was the most dramatic burst of overwater exploration in human prehistory. Until 1200 B.C., the spread of ancient humans from the Asian mainland through Indonesia’s islands to Australia and New Guinea had advanced no farther into the Pacific than the Solomon Islands east of New Guinea. Around that time, a seafaring and farming people, apparently originating from the Bismarck Archipelago northeast of New Guinea, and producing ceramics known as Lapita-style pottery, swept nearly a thousand miles across the open oceans east of the Solomons to reach Fiji, Samoa, and Tonga, and to become the ancestors of the Polynesians. While Polynesians lacked compasses and writing and metal tools, they were masters of navigational arts and of sailing canoe technology. Abundan
t archaeological evidence at radiocarbon-dated sites—such as pottery and stone tools, remains of houses and temples, food debris, and human skeletons—testifies to the approximate dates and routes of their expansion. By around A.D. 1200, Polynesians had reached every habitable scrap of land in the vast watery triangle of ocean whose apexes are Hawaii, New Zealand, and Easter Island.

  Historians used to assume that all those Polynesian islands were discovered and settled by chance, as a result of canoes full of fishermen happening to get blown off course. It is now clear, however, that both the discoveries and the settlements were meticulously planned. Contrary to what one would expect for accidental drift voyages, much of Polynesia was settled in a west-to-east direction opposite to that of the prevailing winds and currents, which are from east to west. New islands could have been discovered by voyagers sailing upwind on a predetermined bearing into the unknown, or waiting for a temporary reversal of the prevailing winds. Transfers of many species of crops and livestock, from taro to bananas and from pigs to dogs and chickens, prove beyond question that settlement was by well-prepared colonists, carrying products of their homelands deemed essential to the survival of the new colony.

  The first expansion wave of Lapita potters ancestral to Polynesians spread eastwards across the Pacific only as far as Fiji, Samoa, and Tonga, which lie within just a few days’ sail of each other. A much wider gap of ocean separates those West Polynesian islands from the islands of East Polynesia: the Cooks, Societies, Marquesas, Australs, Tuamotus, Hawaii, New Zealand, Pitcairn group, and Easter. Only after a “Long Pause” of about 1,500 years was that gap finally breached—whether because of improvements in Polynesian canoes and navigation, changes in ocean currents, emergence of stepping-stone islets due to a drop in sea level, or just one lucky voyage. Some time around A.D. 600-800 (the exact dates are debated), the Cooks, Societies, and Marquesas, which are the East Polynesian islands most accessible from West Polynesia, were colonized and became in turn the sources of colonists for the remaining islands. With New Zealand’s occupation around A.D. 1200, across a huge water gap of at least 2,000 miles, the settlement of the Pacific’s habitable islands was at last complete.