Here is some interesting summer reading for you. Since the day it was discovered by Europeans (Easter Sunday, 1722), Easter Island has had a profound air of mystery about it. In particular, the giant stone statues, numbering in the thousands, have raised questions of how and why the small island population carved and moved these mammoth monoliths (each one weighs several tons). I have personally been fascinated by the place ever since seeing it on In Search Of... back in the 1970s. In Jared Diamond’s bestselling book Collapse, about the decline and fall of several civilizations, he holds up Eastern Island (or Rapa Nui, as it’s called by the natives) as the emblematic example of a ecologically reckless culture that destroyed its own environment, cutting down every last tree on the island to make rollers to move their giant statues. A popular meme has it that the person cutting down the last tree on Easter Island knew perfectly well that it was the last tree and cut it down anyway. How’s that for reckless? The story of Easter Island and its self-generated ecocide has become something of a cautionary tale for us in the West who teeter on the brink of environmental disasters of our own making. (The “cautionary tale” even featured in a science-fiction novel called The Stone Gods about ecocide.) And yet, while this has been the stereotypical view of the Easter Islanders, a fascinating new book revises this history, and extensive new archeological research has revealed that, rather than being the irresponsible tree-cutters portrayed by Thor Heyerdahl and Jared Diamond, among others, the Easter Islanders were actually cautious environmental stewards who did their best to make the most of a hostile environment, pioneering new agricultural techniques and “engineering” soil that could actually grow things. The Statues That Walked: Unraveling the Mystery of Easter Island, by Terry Hunt and Carl Lipo, uncovers new evidence that just about everything we know about Easter Island (which isn’t much, admittedly) is wrong. Take, for example, the cutting down of the palm forest (Jubaea chilensis) that covered much of the island. First of all, the trunks would have been too soft to serve as rollers for the statues (called moai) and would have been crushed by the weight, so they could not have been employed in that fashion. There was also no evidence of large-scale farming or building, which would have been other possible uses for the trees, so that wasn’t it. So why cut them down? Hunt and Lipo turn to other Polynesian islands—specifically Hawaii—for clues, and conclude that it was rats (specifically the Polynesian rat, Rattus exulans) brought to the island by the original settlers (by accident and/or for food) that helped decimate the palm forest. By dint of their rapid reproduction and no natural predators, rats could easily have stripped away the existing flora and eaten seeds and new growth. The authors also uncovered evidence that the Easter Islanders practiced some experimental agricultural techniques, finding themselves on an island—one of the most remote in the world—with poor soil (it lacked phosphorus), limited water, and a wind that promoted dehydration. By experimenting with “lithic mulching,” planting rocks amongst the crops, they could break up the flow of air and wind, cooling the soil during the day and warming it at night. Breaking up larger rocks also released nutrients into the soil, making it cultivatable. The creation of manavai, stone garden walls, also helped grow fragile crops. One of Jared Diamond’s other theses was that Easter Island groaned under the weight of overpopulation, believing that hundreds of people were needed to move the giant moai. Hunt and Lipo dispel this notion, too, by conducting experiments—based on the old island folk legend that “the statues walked” to their locations—showing how only a dozen or two people were needed to “walk” the statues along island roads, much in the same way two or three people might move a large appliance like a refrigerator. So, far from killing themselves and destroying their environment, the Easter Islanders were doing very well, thank you very much—until Europeans and South Americans came to the island, bringing diseases (especially those of the venereal kind), exploitative ranchers, and slave raiding parties. (The Europeans did bring hats, though, which the Easter Island natives apparently went nuts for.) By the beginning of the 20th century, the island’s native population had declined to just over 100. Anyway, it’s a fascinating book about a fascinating place and even if some of the authors’ conclusions are speculation, they are at least plausible given the paucity of evidence. We may never know exactly how or why the statues were created and moved, but The Statues That Walked gets us closer to the best understanding we can hope to obtain. I would have liked more information on the current state of Easter Island (its resurgence in the past few decades has been the result of ecotourism—which, ironically, is stretching island resources pretty thin and may actually result in a kind of ecocide), but it is still a welcome revisionist history. Here’s a review from the Wall Street Journal.