Social facilitation in the acceptance of a novel food:

Does what the others are eating matter?

An experiment in Cebus apella

Elsa Addessi and Elisabetta Visalberghi.

CNR, Italy

The assumption that primates learn to identify the foods they eat from watching what conspecifics eat is widespread (e.g., King 1994; but see Visalberghi, 1994). Visalberghi and Fragaszy (1995) found that the presence of groupmates (and possibly the fact that they are eating) does not increase consumption of familiar foods, but increases consumption of novel foods in groups of capuchins. Previous experiments demonstrated that tufted capuchins eat significantly more of novel foods when in the presence of group members eating the same novel foods. Several processes may have led to these results. The mere presence of group members may reduce the individual's stress of being alone, or its neophobic response and, consequently, may increase its food consumption. The individual may be influenced by what group members do, and local/stimulus enhancement and/or social facilitation may occur. To investigate the above processes, in the present experiment we assessed whether an individual's consumption of novel foods is lower when the individual is (1) alone with nobody in the nearby cage (A condition) than when (2) group members are present in the nearby cage with no food (P condition) or when (3) they are present and eating a familiar food (P & F condition). Subjects (N = 15) were tested with three novel foods, each presented in one condition. Results showed that in both social conditions the more group members by the panel, the more the experimental subject ate. In addition, in the P & F condition there was a significant increase in the acceptance of the three foods, regardless of what group members were eating. We argue that social facilitation of eating is a quicker way to overcome neophobia and only social facilitation of eating what the others are eating can be considered a safe way to learn about a safe diet.

King, B. J. (1994). The information continuum. Santa Fe, NM: School of American Research Press.

Visalberghi, E. (1994). Learning process and feeding behavior in monkeys. In B. J. Galef, M. Mainardi and P. Valsecchi (Eds.), Behavioral aspects of feeding: Basic and applied research on mammals (pp. 257-270). Chur, Switzerland: Harwood Academic Publishers.

Visalberghi, E., & Fragaszy, D. M. (1995). The behaviour of capuchin monkeys (Cebus apella) with novel food: the role of social context. Animal Behaviour, 49, 1089-1095.

Addessi, Elsa

Institute of Psychology, CNR

via Aldrovandi 16 b, I-00197 Roma, Italy

pc@ip.rm.cnr.it