In 1975, the Polynesian Voyaging Society built a replica of an ancient Polynesian voyaging canoe. Voyaging through strange seas of Thought, alone. PVS was established to research and perpetuate traditional Polynesian voyaging methods. Sails allowed Austronesians to embark on long-distance voyaging. These sails allowed Austronesians to embark on long-distance voyaging. Harold Gatty suggested that long-distance Polynesian voyaging followed the seasonal paths of bird migrations. Scientists think that long-distance Polynesian voyaging followed the seasonal paths of birds. Voyaging and culture link all of these islands. Native peoples of the Pacific resumed voyaging again a thousand years later. This became their home base but did not stop them from voyaging onward. The Portuguese had several motives for voyaging south. Older research summarized by Joan Druett assumed that Tupaia's own voyaging experience was limited. Finney disagreed with the accidental voyaging portion of Sharp's hypothesis. This is typically but not always at the end of their voyaging lives.