Thor Heyerdahl (1914 -2002), was a Norwegian ethnologist and adventurer with a background in zoology, botany and geography who organized and led the famous Kon-Tiki (1947) and Ra (1969–70) transoceanic scientific expeditions. Both expeditions were intended to prove the possibility of ancient transoceanic contacts between distant civilizations and cultures. For the most part, Heyerdahl’s theories have not been accepted by anthropologists.
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