>It surprises me
>that you cite the account of it as contested. Seems fairly open and shut, at
>least in broad outline, to me.

Two other factors are commonly cited: the introduction of the Polynesian rat (through it eating palm tress seeds, leading to deforestation) and European settlers:

"While tribal warfare likely reduced the population of Easter Islanders, Hunt suggests that most of the decline probably was resulted from early 18th-century Dutch traders, who brought diseases and took slaves from the island. Research elsewhere indicates that "first contact" diseases—like typhus, influenza and smallpox—carry extremely high mortality rates, often exceeding 90%. The first traders to reach the island likely carried such diseases which would have rapidly spread among the islanders and decimated the population."

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