Thor Heyerdahl, the adventurer, explorer, ethnologist, and author, died on Thursday, 18 April, 2002, at about 7pm. He was 87 years old. His death marked the passing of a long and exceptionally full life.

Early Polynesian Studies

Heyerdahl was born in Larvik, Norway, on 6 October, 1914.

He begun his studies of zoology and geography in earnest at the university of Oslo, and in 1936 he left for Polynesia with his wife, Liv. They made their first stop at a group of islands called Marquesas and the larger island of Fatuhiva, and studied plant and animal life there. However, Heyerdahl was more interested in the origin of the aboriginal population on these isolated Pacific islands, and in 1941 he published the now famous theory that Polynesia was populated as a result of immigration from Peru and Colombia.

Interrupted by the outbreak of the Second World War, Heyerdahl returned to Norway to volunteer for the Free Norwegian Forces, eventually serving in a Norwegian parachute unit in Finnmark.

After the war, Heyerdahl continued his research, only to meet a wall of resistance to his theories among comtemporary scholars. To add weight to his arguments, Heyerdahl decided to build a replica of the aboriginal balsa raft to test his theories.

The Kon-Tiki Voyage

To prove that it had been possible to sail over the Pacific to Polynesia, Heyerdahl set out on the same journey. On 28 April, 1947, he sailed with the raft Kon-Tiki - named after a South American sun god - and a crew of five, from Callao in Peru. They reached the Tuamotu islands in Polynesia on 7 August, after an eight thousand kilometre crossing, which had taken 101 days. The seaworthiness of the aboriginal raft had been proved without question, despite the skepticism that the venture had attracted. It was now beyond dispute that the ancient Peruvians could have reached Polynesia in this manner.

The raft was built as a copy of an old Peruvian balsa raft, and is exhibited at the Kon-Tiki Museum at Bygdøy in Oslo, Norway. The subsequent documentary charting the Kon-Tiki expedition was awarded an Oscar in 1951 - so far the only Oscar that has gone to Norway.

The journey from Peru to Polynesia was followed by expeditions to, among other places, the Galapagos Islands in 1953, and to Easter Island in 1955-56. On both these expeditions, Heyerdahl gathered more evidence to support his Polynesian theory, and the contact with South America.

The Ra Expeditions and Later Life

Heyerdahl's Ra expeditions in 1969 and 1970 showed the reed boats' suitability for sea-journeys. With a crew of six, he again attempted a voyage - from Morocco to America - on the Ra, made of papyrus and modelled on ancient Egyptian models. Although this first trip failed, a second attempt the next year - in Ra II - succeeded. Ra II sailed from Morocco to Barbados, a distance of 5700km, in just 57 days. In 1977, Heyerdahl organised another expedition with a reed boat, the Tigris, which sailed from Iraq to Djibouti.

In the '80s and '90s Heyerdahl led archaeological projects in the Maldives, Easter Island and in Tucume, Peru. His last project was called 'Odin in Azov'. Working from theories based on Snorri Sturlason's writings from the 13th Century, he has been working on links between an ancient tribal leader and the Norse god Odin.

In the last years of his life, Thor Heyerdahl made his home in Tenerife, the Canary Islands, and at Colla Micheri, near Alassio by the Italian riviera.

Throughout his career, Thor Heyerdahl had a strong dedication to international environmental work, and received numerous diplomas as well as honorary doctorates from 11 universities, including his alma mater, the University of Oslo. There can be no doubt that his brilliant and audacious work is among the most important in the field of human migration.