Foraging competence and its impact on social relationships in a socially tolerant wild primate.

Social interactions are crucial for individual health and ultimately fitness, making the choice of social partners evolutionarily relevant. Previous research has shown that individuals who succeed in foraging tasks often receive increased affiliation from group members. Similarly, in a social learning context, individuals who possess valuable information become more attractive social partners. Thus, an individual's role in a foraging context, specifically, whether it is a successful producer, can influence its social relationships. To explore this effect, we examined the interplay between social learning, producing and scrounging behavior, and social relationships in four groups of wild red-fronted lemurs (Eulemur rufifrons; N = 29). We conducted an open diffusion experiment with food boxes that required animals to learn one of two techniques to open them. 16 individuals learned to open them. Initial success was better predicted by use of individual than social information, i.e., manipulating the food boxes vs. time spent watching successful individuals or scrounging. Older males were less successful than females. Scrounging occurred in about 26% of events. The technique used, age and sex of the producer did not predict the number of scroungers. Less successful individuals and males scrounged more often. Successful individuals received more affiliative behavior during the experimental period than in the pre-experimental period, which returned to baseline levels during the post-experimental period. Thus, red-fronted lemurs recognize and reward competent foraging partners socially during periods where they can benefit from them immediately. Together, these results highlight the importance of foraging competence for social integration and partner choice.