Conversation so far:
What was he doing?
In 1955-1956, Heyerdahl organized the Norwegian Archaeological Expedition to Rapa Nui (Easter Island.
Who was apart of this team?
The expedition's scientific staff included Arne Skjolsvold, Carlyle Smith, Edwin Ferdon, Gonzalo Figueroa and William Mulloy.
Heyerdahl and the professional archaeologists.

Question: What did they do while there?
Self-contained rewrite: What did the scientific staff and archaeologists do while at Easter Island?