title: Chimpanzees strategically manipulate what others can see.
abstract: Humans often strategically manipulate the informational access of others to their own advantage. Although chimpanzees know what others can and cannot see, it is unclear whether they can strategically manipulate others' visual access. In this study, chimpanzees were given the opportunity to save food for themselves by concealing it from a human competitor and also to get more food for themselves by revealing it to a human cooperator. When knowing that a competitor was approaching, chimpanzees kept more food hidden (left it covered) than when expecting a cooperator to approach. When the experimenter was already at the location of the hidden food, they actively revealed less food to the competitor than to the cooperator. They did not actively hide food (cover up food in the open) from the competitor, however. Chimpanzees thus strategically manipulated what another could see in order to maximize their payoffs and showed their ability to plan for future situations.
authors.affiliation: Department of Developmental and Comparative Psychology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany, katja_karg@eva.mpg.de.
authors.forename: Katja
authors.initials: K
authors.lastname: Karg
authors.forename: Martin
authors.initials: M
authors.lastname: Schmelz
authors.forename: Josep
authors.initials: J
authors.lastname: Call
authors.forename: Michael
authors.initials: M
authors.lastname: Tomasello
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D003163:Competitive Behavior; D008192:Deception; D005260:Female; D005502:Food; D006801:Humans; D008297:Male; D002679:Pan troglodytes / Q000523:psychology*; D014454:Uganda; D014796:Visual Perception