There is a recent post up over at Tallbloke’s Talkshop: Thor Heyerdal: Retrospective on an Adventurous Anthropologist, which charts the man’s life and career on the occasion of the one hundredth anniversary of his birth: October, 6th 1914.
The article at the Talkshop commented at some length on Heyerdal’s various ocean voyages to support his ideas about trans-cultural diffusion over very long ocean distances.
Heyerdahl in particular inspired by his experiences in the south pacific in French Polynesia was possessed by the idea that the similarities between the famous moai figures of Easter Island and certain sculptures of pre-Columbian Peru indicated the possibility that vayagers from Peru encountered the native inhabitants and this was attested to in the oral legends of the islands inhabitants the Rapa Nui. Examining the possibility of a voyage by ancient Peruvians to Easter Island lead to the famous Kon-Tiki expedition in 1947.
Another, similar, idea that possessed Heyerdahl was that the similarity between the pyramids of the ancient Egyptians and the Mayans indicated a possibility of a previously unrecognized trans-oceanic connection there as well. This lead to the various Ra expeditions between 1969 and 1970.
I had a comment started which rapidly became too large to post there without blushing, so I posted a much abbreviated version there and the full length analysis below.
Heyerdahl was a hugely determined and brave adventurer, a great man and a great inspiration, but not much of a scientist in my opinion. Heyerdahl certainly did prove that it was possible for a Norske to build a raft and to drift across two different oceans following the trade winds – knowing there is someplace to wind up and the possibility of a safe return via boat or aircraft – but not much else in my opinion.
As for embarking on his later quest to effect the transformation the chief of the pantheon of your own culture’s archaic religion to a historical ruler/king somewhere in central Asia, a lot of other people besides Heyerdahl have fallen into that particular folly.
The problem with Heyerdahl’s thinking, and which is pretty common even in academic anthropology and archeology is to mistake a morphological similarity due to parallel evolution with a line of decent – an easy mistake to make.