Testing for anticipation of partners' reciprocity and other social parameters: An experimental approach in wild vervet monkeys (Chlorocebus pygerythrus).

It has been suggested that social challenges in group-living species in which individuals maintain long-term relationships select for advanced cognitive processes. A key challenge for testing this hypothesis is to design experiments that allow the assessment of animals' knowledge of conspecifics and how they use that information to their own advantage. Here, we present data on wild vervets using an experimental paradigm that induced a competitive context.

Female vervet monkeys fine-tune decisions on tolerance versus conflict in a communication network.

Group living promotes opportunities for both cooperation and competition. Selection on the ability to cope with such opposing social opportunities has been proposed as a driving force in the evolution of large brains in primates and other social species. However, we still know little about the degree of complexity involved in such social strategies.

Intergroup Variation of Social Relationships in Wild Vervet Monkeys: A Dynamic Network Approach.

Social network analysis is a powerful tool that enables us to describe and quantify relationships between individuals. So far most of the studies rely on the analyses of various network snapshots, but do not capture changes over time. Here we use a stochastic actor-oriented model (SAOM) to test both the structure and the dynamics of relationships of three groups of wild vervet monkeys.

Wild Vervet Monkeys Trade Tolerance and Specific Coalitionary Support for Grooming in Experimentally Induced Conflicts.

Grooming is a key social behavior in many primate species. Research has focused on three important aspects: the short- and long-term trading patterns of grooming for itself and/or for other commodities like tolerance or coalitionary support, the issue of whether exchanges are a convincing example for reciprocity, and what decision rules underlie trading. These issues remain largely unresolved due to the correlative nature of observational studies and the rarity of experimental studies.

Social networks in primates: smart and tolerant species have more efficient networks.

Network optimality has been described in genes, proteins and human communicative networks. In the latter, optimality leads to the efficient transmission of information with a minimum number of connections. Whilst studies show that differences in centrality exist in animal networks with central individuals having higher fitness, network efficiency has never been studied in animal groups.

Potent social learning and conformity shape a wild primate's foraging decisions.

Conformity to local behavioral norms reflects the pervading role of culture in human life. Laboratory experiments have begun to suggest a role for conformity in animal social learning, but evidence from the wild remains circumstantial. Here, we show experimentally that wild vervet monkeys will abandon personal foraging preferences in favor of group norms new to them.

Third-party ranks knowledge in wild vervet monkeys (Chlorocebus aethiops pygerythrus).

The Machiavellian/Social Intelligence Hypothesis proposes that a complex social environment selected for advanced cognitive abilities in vertebrates. In primates it has been proposed that sophisticated social strategies like obtaining suitable coalition partners are an important component of social intelligence. Knowing the rank relationships between group members is a basic requirement for the efficient use of coalitions and the anticipation of counter-coalitions.