Instead of being killed and eaten, did the Harvard-educated American reject his civilised past and join a tribe of cannibals?
The riddle started in 1961 when the young graduate swapped his entitled Manhattan life for the privations of Dutch New Guinea.
The highlands are much cooler and have even been known to experience snowfalls.
Papua New Guinea is part of a chain of islands stretching between Asia and Australia.
The official explanation advanced by the former colony’s Dutch rulers was that he drowned after he tried to swim to shore from his capsized boat.