The Acali expedition was a 1973 social experiment that aimed to investigate interpersonal relationships in conditions of limited space and social isolation. The experiment was conceived by Mexican anthropologist Santiago Genovés, who had previously been a crew member of Thor Heyerdahl's Ra expedition. The participants showed a restraint towards aggression, which frustrated Genovés and led him to start to try to create conflict, and at one point he took command of the float. Despite these attempts, the group remained peaceful.