today by genetic and archaeological data, indicating that he was patently wrong." A 2009 study by the Norwegian researcher Erik Thorsby suggested that there was some merit to Heyerdahl's ideas and that, while Polynesia was colonised from Asia, some contact with South America also existed. Some critics suggest, however, that Thorsby's research is inconclusive because his data may have been influenced by recent population contact. A 2014 research project indicates that the South American component of the Easter Island people's genomes pre-dates European contact. The research team, including Anna-Sapfo Malaspinas (from the Natural History Museum of Denmark), analysed the genomes of 27 native Rapanui people and found that their DNA was on average 76 per cent Polynesian, 8 per cent Native American and 16 per cent European. Analysis showed that "although the European lineage could be explained by contact with white Europeans after the island was 'discovered' in 1722 by Dutch sailors, the South American component was much older, dating to between about 1280 and 1495, soon after the island was first colonised by Polynesians in around 1200." Together with ancient skulls found in Brazil – with solely Polynesian DNA – this does suggest some pre-European-contact travel to and from South America from Polynesia. A study based on over one hundred Rapanui DNA sequences published in Nature in July 2020 showed that a genetic contact event occurred, circa 1200 AD, between Polynesian individuals and a Native American group most closely related to the indigenous inhabitants of present-day Colombia. Expedition to Easter Island In 1955–1956, Heyerdahl organised the Norwegian Archaeological Expedition to Easter Island. The expedition's scientific staff included Arne Skjølsvold, Carlyle Smith, Edwin Ferdon, Gonzalo Figueroa and William Mulloy. Heyerdahl and the professional archaeologists who travelled with him spent several months on Easter Island investigating several important archaeological sites. Highlights of the project include experiments in the carving, transport and erection of the notable moai, as well as excavations at such prominent sites as Orongo and Poike. The expedition published two large volumes of scientific reports (Reports of the Norwegian Archaeological Expedition to Easter Island and the East Pacific) and Heyerdahl later added a third (The Art of Easter Island). Heyerdahl's popular book on the subject, Aku-Aku was another international best-seller. In Easter Island: The Mystery Solved (Random House, 1989), Heyerdahl offered a more detailed theory of the island's history. Based on native testimony and archaeological research, he claimed the