Heyerdahl, Thor (1914–2002), controversial Norwegian scientist and adventurer, who was born at Larvik. While at Oslo University he became fascinated by the study of early civilizations and movements of oceanic peoples. In 1937 he went to the Marquesas Islands in the Pacific to continue his research at first hand. While there, he first began to suspect that the Polynesian civilization might have had its roots in an earlier migration of South American Indians; though it seemed impossible to conceive how the long ocean voyage could have been made without ships, unknown in the Pacific at that time, and with no knowledge of
navigation and ocean
currents.
Heyerdahl decided that if his theories were correct, it could have happened by drifting across the ocean on
rafts, and in 1947 he set about testing his theory. Using only such fastenings as would have been available to the Indians at the time of their supposed migration, he built a raft from the trunks of the indigenous Ochroma lagopus tree (also known as ‘balsa’), and with five companions set off to drift and sail across the Pacific from Callao, Peru. The raft, named
Kon-Tiki after the legendary sun king of the South American Indians, was 13.7 metres (45 ft) long with a
beam of 5.5 metres (18 ft), and was rigged with a short mast and single square sail.
Aided by the Humboldt current, and using
plankton and
fish as part of their diet, the six men covered 6,880 kilometres (4,300 mls.) in 101 days before beaching on Raroia Reef, in the Tuamoto Islands. This proved that his theory about the colonization of the Polynesian islands was a physical possibility, and that it could have come from the east, and not from the west as was the current academic thinking. It is now accepted that there was indeed early contact between South America and Polynesia. However, anthropologists, aided by modern genetics, have found no evidence that intermarriage occurred on a scale to support Heyerdahl's theory of colonization, and it seems more probable that early sailing rafts first sailed eastwards not westwards.
After mounting expeditions to the Galapagos and Easter Islands in pursuit of his theory, Heyerdahl turned his attention to very early Egyptian voyages. His interest in these had been sparked, not just by ancient accounts, but by the small reed boats he had found on Lake Titicaca, and the discovery on the Galapagos of what he believed to be the images of triple-masted boats made of reed. This led him to speculate on the possibility that ancient Egyptians may have crossed the Atlantic in boats made of papyrus reed, and he determined, with the aid of companions, to attempt an ocean passage in such a boat. He constructed the 15-metre (49-ft)
Ra, and when this disintegrated in heavy seas close to the West Indies, he built the slightly shorter
Ra II, on which, in 1970, he crossed the Atlantic from Safi, Morocco, to Bridgetown, Barbados. In covering 3,300
nautical miles (6,578 km) in 57 days, he demonstrated that oceanic voyages by the ancient Egyptians were at least a possibility. Then in 1978 he built another 15-metre (49-ft) reed boat, called
Tigris, and, with a crew of eleven, sailed it down the River Tigris to the Indian Ocean, again seeking to prove a possible communication between different early civilizations.
Heyerdahl wrote two best-selling books about his adventures:
The Kon-Tiki Expedition (1948) and
Aku-Aku: The Secret of Easter Island (1958), and published a number of others. He made several documentary films—his one on the
Kon-Tiki won an Oscar in 1951—and lectured extensively. As one of his obituarists pointed out, he encouraged conservation and environmental awareness, and in the field of Polynesian studies contributed, among other enduring ideas, the notion that the sea was a connector, not a barrier.
