

Did Easter Island get 'ratted' out? By Dan Vergano, USA TODAY WASHINGTON  Rats and Europeans are likely to blame for the mysterious demise of Easter Island, a team of anthropologists suggests. Easter Island. Courtesy: Terry Hunt, University of Hawaii The fate of the people who built hundreds of 10-ton stone statues on the South Pacific island and then vanished has long been seen as a cautionary environmental tale. Natives deforested the island paradise to transport the statues, the story goes, triggering erosion that damaged farmlands. And then they supposedly bumped themselves off in a cannibalistic civil war in about 1650. But anthropologist Terry Hunt of the University of Hawaii at Manoa first blames the Polynesian rat. The rats probably deforested the 66-square-mile island's 16 million palm trees. "Palm tree seeds are filet mignon to rats," Hunt says. Working with colleagues at the island's anthropology museum and elsewhere since 2001, Hunt's team has undertaken an extensive archaeological survey of the island: • Charcoal remains show that Polynesians settled the island in 1200, much later than supposed from earlier, inaccurate dates of such deposits. • Pollen and ash deposits show that the number of palm trees declined swiftly in the years before fires, the signature of human occupation, appeared on the island. • Rat remains indicate that the rodent population spiked at 20 million from 1200 to 1300 and then dropped off to a mere 1 million after the trees were gone. • Skeletal remains and digs of old homes show little or no evidence of early warfare. Courtesy: Terry Hunt, University of Hawaii The University of Hawaii archaeology field team. Instead, the disappearance of Easter Islanders probably was caused by visiting Dutch traders in the 1700s, who brought diseases and, later, slave raiding, says Hunt, who presented his findings at an American Anthropological Association meeting last week. Older explanations essentially blamed the victims for their demise, says archaeologist Patricia McAnany of Boston University. The island still represents a cautionary tale, she says, but one of the dangers of invasive species. But New Zealand's John Flenley of Massey University calls the idea "most unlikely," saying rats didn't deforest other Polynesian islands. Hunt counters that deforestation of palm trees by Polynesian rats occurred on the Hawaiian islands. And the Easter Island palms were uniquely vulnerable because the rats had no predators and the trees didn't grow at elevations too high for them to reach. Hunt suggests that about 50 settlers first landed on the island and grew to a stable population of at least 3,000 people by 1650. That seems reasonable, says mathematician William Basener of the Rochester (N.Y.) Institute of Technology, an expert in population models.