Monday, December 16, 2013

Did Rats Eradicate Easter Island Trees?

New speculation on what caused the demise of civilization on Easter Island gives the ancient islanders more credit for innovative adaptations to environmental problems, though ultimately the story ends on the same desolate note.
The updated theory and sequence of events come from anthropologists Terry Hunt and Carl Lipo from the University of Hawaii. According to NPR:
Professors Hunt and Lipo say fossil hunters and paleobotanists have found no hard evidence that the first Polynesian settlers set fire to the forest to clear land — what's called "large scale prehistoric farming." 
The trees did die, no question. But instead of fire, Hunt and Lipo blame rats . . . Polynesian rats (Rattus exulans) stowed away on those canoes, Hunt and Lipo say, and once they landed, with no enemies and lots of palm roots to eat, they went on a binge, eating and destroying tree after tree, and multiplying at a furious rate.
They say the rats played havoc with the island’s trees, causing a massive degrading of vegetation and eliminating several animal species. The NPR report concludes: “On Easter Island, people learned to live with less and forgot what it was like to have more. Maybe that will happen to us. There's a lesson here. It's not a happy one.”