Polynesia was settled in a series of extraordinary voyages across an ocean spanning one third of the Earth¹, but the sequences of islands settled remain unknown and their timings disputed. Currently, several centuries separate the dates suggested by different archaeological surveys^2,3,4. Here, using genome-wide data from merely 430 modern individuals from 21 key Pacific island populations and novel ancestry-specific computational analyses, we unravel the detailed genetic history of this vast, dispersed island network. Our reconstruction of the branching Polynesian migration sequence reveals a serial founder expansion, characterized by directional loss of variants, that originated in Samoa and spread first through the Cook Islands (Rarotonga), then to the Society (Tōtaiete mā) Islands (11th century), the western Austral (Tuha’a Pae) Islands and Tuāmotu Archipelago (12th century), and finally to the widely separated, but genetically connected, megalithic statue-building cultures of the Marquesas (Te Henua ‘Enana) Islands in the north, Raivavae in the south, and Easter Island (Rapa Nui), the easternmost of the Polynesian islands, settled in approximately ad 1200 via Mangareva.

波利尼西亚是在一系​​列跨越地球^三分之一的海洋的非凡航行中定居下来的，但定居岛屿的顺序仍然未知，而且它们的时间也存在争议。目前，不同考古调查显示的日期相隔几个世纪^2,3,4 。在这里，我们利用来自 21 个主要太平洋岛屿种群的 430 个现代个体的全基因组数据和新颖的特定祖先计算分析，揭示了这个巨大、分散的岛屿网络的详细遗传历史。我们对分支波利尼西亚移民序列的重建揭示了一系列创始人扩张，其特征是变异的定向丢失，起源于萨摩亚并首先传播到库克群岛（拉罗汤加），然后传播到社会（Tōtaiete mā）群岛（11世纪），西南方 (Tuha'a Pae) 群岛和土阿莫土群岛 (12 世纪)，最后到北部的马克萨斯 (Te Henua 'Enana) 群岛、北部的 Raivavae 群岛，这些文化虽然相距甚远，但在基因上却有联系。南部和波利尼西亚群岛最东端的复活节岛（拉帕努伊）大约于公元1200 年通过曼阿雷瓦 (Mangareva) 定居。