Isotopes and the Polynesian Expansion

Robin Moroney writes in the WSJ's Informed Reader blog of new evidence that confirms Polynesian oral traditions of Hawaii-Tahiti migrations: isotope analysis places prehistoric Hawaiian tools on an atoll near Tahiti. (To those of us accustomed thinking of them as merely islands in the same ocean, we're talking about 2500 mile distances.) The prospect of crossing that stretch of the Pacific in an open, stone-age vessel kind of makes my rant about air travel... pathetic.