Recent research shows rats, not men, to blame for death of Easter Island:
Almost all of the palm seed shells discovered on the island were found to have been gnawed by rats. Thousands of rat bones have been found, and crucially, much of the damage to forestry appears to have been done before evidence of fires on the island. Evidence from other Pacific islands also confirms how devastating rats can be.Exactly how rats got on to the island is not known, although one theory is that they arrived as stowaways in the first canoes of Polynesian colonists. Once they arrived, the rats found palm nuts offered an almost unlimited high-quality food supply.
Under ideal conditions, rats reproduce so rapidly that their numbers double every 47 days; unchecked, a single mating pair can produce a population of nearly 17 million in just over three years. Research in the Northwest Hawaiian Islands shows that when available food is taken into account, populations can reach 75 to the acre.
“At 75 rats per acre, the rat population of Easter Island could have exceeded 3.1 million,” says the report. The Hawaiian research demonstrates that rats were capable, on their own, of deforesting large lowland coastal areas in about 200 years or less. “In the absence of effective predators, rats alone could eventually result in deforestation.”
Dr Hunt says the environmental catastrophe of Easter Island has been masked by speculation about the intentions of people cutting down the last tree: “Indeed, the last tree may simply have died. Rats may have simply eaten the last seeds.
(Hat tip to Todd.)