The downfall of Easter Island may have had more to do with preexisting environmental conditions than degradation by humans, according to a new study of the remote speck of land made famous by its enormous stone-head statues. 
 
 Easter Island, also known as Rapa Nui, was first settled around A.D. 1200, and Europeans landed on its shores in 1722. The circumstances surrounding the collapse of the indigenous population of Rapa Nui are hotly debated both in academia and popular culture. Scientist and author Jared Diamond argued in his 2005 book "Collapse: How Societies Choose to Fail or Succeed" (Viking Press) that prior to European contact, the indigenous people of the island degraded the environment to the extent that they could no longer thrive. 
 
 The new study suggests that Easter Island's people were, indeed, suffering before Europeans came along. The story of their downfall, however, may be less about environmental degradation than the pre-existing environmental constraints of the 63-square-mile (163 square kilometers) isle. [Image Gallery: The Walking Statues of Easter Island] 
 
 "The results of our research were really quite surprising to me," said study co-author Thegn Ladefoged, an anthropologist at the University of Auckland in New Zealand. "Indeed, in the past, we've published articles about how there was little evidence for pre-European-contact societal collapse." 
 
 Collapse of civilization? 
 
 The new study challenged Ladefoged and his colleagues' view. Changes on Easter Island have been well documented, archaeologically. Over time, elite dwellings were destroyed, inland agricultural fields were abandoned, and people took refuge in caves and began manufacturing more and more spear points made out of volcanic glass called obsidian, perhaps suggesting a period of war and upheaval. 
 
 The problem with pinning down the island's history, according to the researchers, is that the dates of all these events and abandonments remain murky. Going into the study, the researchers expected to find that most of the disaster occurred after Europeans arrived, Ladefoged told Live Science. 
 
 To clarify the timeline, the researchers analyzed more than 400 obsidian tools and chipped-off obsidian flakes from six sites scattered around the island, focusing in particular on three with good information on climate and soil chemistry. 
 
 Obsidian absorbs water when exposed to air. By measuring the amount of water absorption in the surfaces of the obsidian tools and flakes, the research team was able to gauge how long those surfaces have been exposed, thus revealing when the tools were made. A greater number of tools from a certain time period indicates heavier human use of that area during that time. [History's 10 Most Overlooked Mysteries] 
 
 Natural challenges 
 
 The obsidian dates varied widely across the sites. Site 1, on the northwestern coast of the island, saw a steady increase in use between about 1220 and 1650, with a fast decline starting after 1650 — long before Europeans arrived on the island. 
 
 Site 2, an interior mountainside site, saw a rapid increase in land use between about 1200 and 1300, a slower increase until about 1480, and then constant use until a decline that started between 1705 and 1710, also before European contact. By the time Europeans came along, coastal Site 1 was at about 54 percent of its peak land use, and mountainous Site 2 was at only about 60 percent. 
 
 Site 3 told a different story. This near-coastal area saw a slow increase in human activity between 1250 and 1500, and then a faster increase until about 1690, after which settlement remained fairly constant until after European contact. In fact, the decline in use of this site didn't begin until 1850 or later, the researchers found. 
 
 The differing climates of the sites may explain the uneven decline, the researchers said. Site 1 is in the rain shadow of the volcano Ma'unga Terevaka, making it prone to droughts. Site 2 is wetter, but its soil fertility is low. Site 3, the longest-lasting spot, is both rainy and fertile. 
 
 What this means is that the people of Easter Island may have been struggling against natural environmental barriers to success, rather than degrading the environment themselves, the researchers reported Monday (Jan. 5) in the journal Proceedings of the National Academy of Sciences. 
 
 "It is clear that people were reacting to regional environmental variation on the island before they were devastated by the introduction of European diseases and other historic processes," Ladefoged said. The next step, he said, would be to take a detailed look at the archaeological remnants of dwellings on the island over time to better understand how humans and the environment interacted. 
 
 Follow Stephanie Pappas on Twitter and Google+. Follow us @livescience, Facebook & Google+. Original article on Live Science. ||||| (CNN) For decades, mystery has swirled around what happened to the founding population of the remote Easter Island, known for its towering stone statues depicting large carved heads. A long-held theory suggests that after the islanders set up camp and carved the giant statues, they destroyed their own society through infighting and a depletion of natural resources. 
 
 But a new study suggests a different scenario entirely, and the islanders could have a more complex history than previously believed. 
 
 Many aspects of the island, the statues and the Polynesian seafarers who arrived there 900 years ago have been studied over the years. But a study published Monday in the Journal of Pacific Archaeology uses multiple data sets from recent excavations to provide a better understanding of the society that created the statues and how they were carved. 
 
 So the researchers used an unlikely method to study the society and discern what might have happened: a chemical analysis of stone tools used on the statues. 
 
 What they learned from excavating four of the statues and the volcanic stone basalt tools used to carve them painted a different picture: a sophisticated and collaborative society. 
 
 "The idea of competition and collapse on Easter Island might be overstated," said lead study author Dale Simpson Jr., an archaeologist at the University of Queensland, in a statement. "To me, the stone carving industry is solid evidence that there was cooperation among families and craft groups." 
 
 Moai are spread across the landscape of Easter Island. 
 
 A complex society 
 
 Easter Island is 2,300 miles off the coast of Chile. About 900 years ago, the founding population landed on the island, called Rapa Nui in the local language. These Polynesian seafarers came on two canoes and were led by Hotu Matu'a, who would become the island's first chief, according to oral tradition. 
 
 The population soared to include thousands of people, and they carved full-body figures, called moai, to represent important Rapa Nui ancestors. There are nearly a thousand statues, many buried up to their heads due to the passage of time. The largest statue is over 70 feet tall. 
 
 Their sheer size and number is indicative of a complex, sophisticated society, according to the researchers. 
 
 "Ancient Rapa Nui had chiefs, priests, and guilds of workers who fished, farmed, and made the moai. There was a certain level of sociopolitical organization that was needed to carve almost a thousand statues," Simpson said. 
 
 During the statue excavations, Jo Anne Van Tilburg, director of the Easter Island Statue Project, and her Rapa Nui excavation team recovered about 1,600 stone tools. They did a close chemical and mass spectrometer analysis of fragments from 17 of the tools, called toki. 
 
 "We wanted to figure out where the raw materials used to manufacture the artifacts came from," said Laure Dussubieux, a study co-author and Field Museum scientist, in a statement. "We wanted to know if people were taking material from close to where they lived." 
 
 The location is key because there are three sources, or quarries, where the islanders could have gathered material for tools. The basalt quarries cover the size of two football fields. Basalt samples reveal their sources through their chemical elements, which link back to the geology of the site. 
 
 "The majority of the toki came from one quarry complex -- once the people found the quarry they liked, they stayed with it," Simpson said. "For everyone to be using one type of stone, I believe they had to collaborate. That's why they were so successful -- they were working together." 
 
 Looking ahead 
 
 This contrasts with the idea that the residents ran out of resources and fought amongst themselves, the researchers said. But later on, it is believed that the arrival of colonists and the institution of slavery decimated the population. 
 
 "There's so much mystery around Easter Island, because it's so isolated, but on the island, people were, and still are, interacting in huge amounts," Simpson said. "There are thousands of Rapa Nui people alive today -- the society isn't gone." 
 
 But the researchers also urge caution and believe that this study is just the beginning, laying the groundwork for more research. 
 
 "The near exclusive use of one quarry to produce these seventeen tools supports a view of craft specialization based on information exchange, but we can't know at this stage if the interaction was collaborative," Van Tilburg said. "It may also have been coercive in some way. Human behavior is complex. This study encourages further mapping and stone sourcing, and our excavations continue to shed new light on moai carving."
– The tale of the demise of Easter Island's people may have to be rewritten. The story has long held that infighting as resources ran out was one of the main drivers of the collapse, but a new study published in the Journal of Pacific Archaeology suggests a different scenario. CNN reports on the "unlikely method" of examining the society via of some of the stone tools used to carve the island's famous stone figures: Researchers performed a chemical analysis on four of the statues and fragments from 17 of the roughly 1,600 basalt tools, called toki, that had been excavated. The goal was to determine where the basalt had come from. There were three quarries on the island that were potential sources of the volcanic rock; the key discovery is that there was "near exclusive" use of a single quarry to make the toki. Here's the jump researchers are making from there, per a press release: Lead study author Dale Simpson Jr. sees that as "solid evidence that there was cooperation among families and craft groups. ... The idea of competition and collapse on Easter Island might be overstated." But Jo Anne Van Tilburg, who led the excavations, cautions against coming to an overstated conclusion in this case. She says the findings bolster the view "of craft specialization based on information exchange, but we can't know at this stage if the interaction was collaborative. It may also have been coercive in some way. Human behavior is complex." (This separate study pushes the same theory but based on different evidence: obsidian.)