Collapse_ How Societies Choose to Fail or Succeed - Jared Diamond [50]
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.