Determining the value of social companionship to captive tufted capuchin monkeys (Cebus apella) (2000)

Dettmer, E., Fragaszy, D. M.

Abstract

To measure the need for social companionship, subjects [6 males, 1 female] were asked to choose between two commodities: food and social companionship. The only time subjects showed a food preference was when they were provided with a social companion but deprived of food for at least 12 hr prior to testing trials. .. Tufted capuchin monkeys value social companionship as they value food: It is a necessity, not a luxury.