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Code and data tables to reproduce the results from the article 'Social dynamics of vervet monkeys are dependent upon group identity.' (Kerjean, Elena ; De Waal, Erica ; Canteloup, Charlotte)

* Correspondence should be addressed to Manuel Bohn (manyprimates@gmai l.com). Short-term memory is implicated in a range of cognitive abilities and is critical for understanding primate cognitive evolution. To investigate the effects of phylogeny, ecology and sociality on short-term memory, we tested the largest and most diverse primate sample to date (421 non-human primates across 41 species) in an experimental delayed-response task. Our results confirm previous findings that longer delays decrease memory performance across species and taxa. Our analyses demonstrate a considerable contribution of phylogeny over ecological and social factors on the distribution of short-term memory performance in primates; closely related species had more similar short-term memory abilities. Overall, individuals in the branch of Hominoidea performed better compared to Cercopithecoidea, who in turn performed above Platyrrhini and Strepsirrhini. Interdependencies between phylogeny and socioecology of a given species presented an obstacle to disentangling the effects of each of these factors on the evolution of short-term memory capacity. However, this study offers an important step forward in understanding the interspecies and individual variation in short-term memory ability by providing the first phylogenetic reconstruction of this trait’s evolutionary history. The dataset constitutes a unique resource for studying the evolution of primate cognition and the role of short-term memory in other cognitive abilities. Publisher PDF

Theory of Mind is the set of cognitive abilities allowing an individual to put himself in the place of others. Considered as specifically human for a long time, more and more complex social behaviours are reported in great apes, and more recently in some monkeys’ species. This work focuses on attention, perception and intention reading abilities in macaques in cooperative or competitive experiments and in interspecific and intraspecific situations. In these experiment, macaques behaved differently according to the attentional state, visual perception and intentions of their partners. However, the underlying mechanisms of these complex behaviours remain uncertain. Nonhuman primates would thus be very good behaviour readers, capable of decoding others behaviours via associative learning but could also use mental representations., La Théorie de l’Esprit est l’ensemble des capacités cognitives permettant à un individu de se mettre à la place d’autrui. Longtemps considérée comme spécifiquement humaine, de plus en plus de comportements sociaux complexes sont rapportés chez les grands singes et plus récemment chez certaines espèces de singes, rendant son existence au sein d’autres espèces hautement débattue. Ce travail s’intéresse aux capacités de macaques à discriminer l’attention, la perception et les intentions d’autrui en situation de coopération ou de compétition, intraspécifique ou interspécifique. Dans ces expériences, les macaques se comportaient différemment selon les états d’attention, la perception visuelle et les intentions de leurs partenaires. Toutefois, les mécanismes sous-jacents à ces comportements complexes restent incertains. Les primates non humains peuvent en effet être de très bons lecteurs de comportements, capables de déchiffrer les comportements des autres sur la base d’apprentissages associatifs, mais pourraient également faire usage de représentations mentales.

International audience; We review four studies investigating hand preferences for grasping versus pointing to objects at several spatial positions in human infants and three species of nonhuman primates using the same experimental setup. We expected that human infants and nonhuman primates present a comparable difference in their pattern of laterality according to tasks. We tested 6 capuchins, 6 macaques, 12 baboons, and 10 human infants. Those studies are the first of their kind to examine both human infants and nonhuman primate species with the same communicative task. Our results show remarkable convergence in the distribution of hand biases of human infants, baboons and macaques on the two kinds of tasks and an interesting divergence between capuchins' and other species' hand preferences in the pointing task. They support the hypothesis that left-lateralized language may be derived from a gestural communication system that was present in the common ancestor of macaques, baboons and humans. (c) 2013 Wiley Periodicals, Inc. Dev Psychobiol 55: 662-671, 2013.

The present study investigated the understanding of goal-directed actions in Tonkean macaques (Macaca tonkeana) using the unwillingversusunable paradigm, previously used in several species. Subjects were tested in three experimental conditions that varied according to the goal-directed actions of a human actor. In the “unwilling” condition, the actor was capable of giving the subject food but unwilling to do it; in the “unable” condition, she was willing to give food but was unable to do it because of a physical barrier; and in the “distracted” condition, she was occupied by manipulating a pebble instead of food. We report for the first time that Tonkean macaques, like capuchins, chimpanzees and human infants, behaved differently across these experimental conditions. They attempted to grasp food in the actor’s hand significantly more and displayed more threats in the presence of an unwilling actor rather than an unable or a distracted one. Inversely, they begged significantly more and displayed more frustration behaviors facing a distracted and unable experimenter rather than an unwilling one. These results suggest that Tonkean macaques understand human goal-directed actions by predicting whether they were likely to obtain food merely based on movements, cue and motor intentions reading and understanding of physical constraints.

The complex social environments of primates create opportunities for engaging in tactical deception, especially for subordinate individuals. We analysed the behaviour of subordinate Tonkean macaques with dominant conspecifics in an experimental food competition context. The subordinate macaque could see two pieces of food in a test area, but only one piece was visible to the dominant. Both individuals were released into the test area at the same time or with the subordinate given a short head start on the dominant. Here, based on video analysis of the subordinates’ behaviours, we describe and classify functionally deceptive behaviours displayed by subordinates, and report factors that influenced these behaviours. Subordinates used several types of tactical deception, including concealment and distraction, especially when paired with competitors of much higher social rank, and they obtained the hidden food more frequently when they used a combination of tactics rather than only one.