Who is Erik Hesselberg from Kon-Tiki: Across the Pacific by Raft and what is their importance?

Erik is the crew's navigator. He keeps track of where they are on a chart and estimates where they will be, given the current conditions. Egged on by other shipmates, Erik throws a harpoon deep into the whale shark's head, which encourages the beast to leave from the vicinity of the raft. Erik is the musician and the artist of the crew. He ships a guitar, plays and sings traditional Polynesian tunes, and paints the face of Kon Tiki on the sail.