Pre-Columbian rafts voyaged as far as Mexico and introduced metallurgy to the civilizations of that country. Some scholars and adventurers of the 20th and 21st century have asserted that the rafts and their crews journeyed thousands of miles across the Pacific to Polynesia, most notably Thor Heyerdahl who reached Polynesia on the Kon-Tiki raft. Several other people and groups have also built rafts based on prehistoric models and undertaken trans-Pacific voyages. Balsa is the Spanish word for raft. The use of rafts for commerce on the coasts of Peru and Ecuador, from northern Chile to southern Colombia, continued until the late 19th
Mau Piailug prevent debate among scholars. Before the "Hōkūle‘a" voyage in 1976, academic debate about the settlement of Polynesia was divided between several schools of thought. Norwegian ethnographer Thor Heyerdahl hypothesized that the Pacific was settled by voyages from South America and set out to prove that with his "Kon-Tiki" expedition. Scholars did not take Heyerdahl's hypothesis seriously. New Zealander Andrew Sharp proposed the accidental voyaging hypothesis in 1957, which (erroneously) argued that Oceania was too vast to have been settled by intentional voyaging so migrations must have happened by accidental drift voyages. Sharp granted that Polynesians likely settled the Pacific from