TONGA: The site of Nukuleka in Tonga is the oldest known site occupied by the Lapita peoples who initially settled remote Oceania, but it has been difficult to date the first settlement precisely. Scientists have now used uranium-thorium dating on thirteen small coral files to find that people of the Lapita culture arrived between 2,830 and 2,846 years ago, nailing down the founding event of Polynesia with unprecedented precision. —Samir S. Patel