Contextualised behavioural measurements of personality differences obtained in behavioural tests and social observations in adult capuchin monkeys (Cebus apella)

We applied a new framework for behavioural research on personality differences in 26 adult tufted capuchin monkeys. Using the Behavioural Repertoire x Environmental Situations Approach, we generated systematically 20 non-lexical emic personality constructs that have high ecological validity for this species. For construct operationalisation, we obtained 146 contextualised behavioural measures repeatedly in 15 experimental situations and 2 group situations using computerised and video-assisted methods. A complete repetition after a 2–3-week break within a 60-day period yielded significant test–retest reliability from individual-oriented and variable-oriented viewpoints at different levels of aggregation. In accordance with well-established findings on cross-situational consistency, internal consistency was only moderate. This new and important finding highlights fundamental differences between behavioural approaches and judgment-based approaches to personality differences

Lack of prosociality in great apes, capuchin monkeys and spider monkeys : convergent evidence from two different food distribution tasks

This work was conducted while the first author held a Humboldt Research Fellowship for Postdoctoral Researchers (Humboldt ID no. 1138999).Prosociality can be defined as any behaviour performed to alleviate the needs of others or to improve their welfare. Prosociality has probably played an essential role in the evolution of cooperative behaviour and several studies have already investigated it in primates to understand the evolutionary origins of human prosociality. Two main tasks have been used to test prosociality in a food context. In the Platforms task, subjects can prosocially provide food to a partner by selecting a prosocial platform over a selfish one. In the Tokens task, subjects can prosocially provide food to a partner by selecting a prosocial token over a selfish one. As these tasks have provided mixed results, we used both tasks to test prosociality in great apes, capuchin monkeys and spider monkeys. Our results provided no compelling evidence of prosociality in a food context in any of the species tested. Additionally, our study revealed serious limitations of the Tokens task as it has been previously used. These results highlight the importance of controlling for confounding variables and of using multiple tasks to address inconsistencies present in the literature.PostprintPeer reviewe

Neonatal Imitation in Rhesus Macaques

The emergence of social behaviors early in life is likely crucial for the development of mother–infant relationships. Some of these behaviors, such as the capacity of neonates to imitate adult facial movements, were previously thought to be limited to humans and perhaps the ape lineage. Here we report the behavioral responses of infant rhesus macaques (Macaca mulatta) to the following human facial and hand gestures: lip smacking, tongue protrusion, mouth opening, hand opening, and opening and closing of eyes (control condition). In the third day of life, infant macaques imitate lip smacking and tongue protrusion. On the first day of life, the model's mouth openings elicited a similar matched behavior (lip smacking) in the infants. These imitative responses are present at an early stage of development, but they are apparently confined to a narrow temporal window. Because lip smacking is a core gesture in face-to-face interactions in macaques, neonatal imitation may serve to tune infants' affiliative responses to the social world. Our findings provide a quantitative description of neonatal imitation in a nonhuman primate species and suggest that these imitative capacities, contrary to what was previously thought, are not unique to the ape and human lineage. We suggest that their evolutionary origins may be traced to affiliative gestures with communicative functions

Artifact and Artifact Categorization: Comparing Humans and Capuchin Monkeys

International audienceWe aim to show that far-related primates like humans and the capuchin monkeys show interesting correspondences in terms of artifact characterization and categorization. We investigate this issue by using a philosophically-inspired definition of physical artifact which, developed for human artifacts, turns out to be applicable for cross-species comparison. In this approach an artifact is created when an entity is intentionally selected and some capacities attributed to it (often characterizing a purpose). Behavioral studies suggest that this notion of artifact is not specific to the human kind. On the basis of the results of a series of field observations and experiments on wild capuchin monkeys that routinely use stone hammers and anvils, we show that the notions of intentional selection and attributed capacity appear to be at play in capuchins as well. The study also suggests that functional criteria and contextualization play a fundamental role in terms of artifact recognition and categorization in nonhuman primates

The Project IM-CLeVeR - Intrinsically Motivated Cumulative Learning Versatile Robots: A Tool-box for Research on Intrinsic Motivations and Cumulative Learning

The goal of this paper is to furnish a tool-box for research on intrinsic motivations and cumulative learning based on the main ideas produced within the Integrated Project "IM-CLeVeR - Intrinsically Motivated Cumulative Learning Versatile Robots". IM-CLeVeR is a project funded by the European Commission under the 7th Framework Programme (FP7/2007-2013), \u27\u27Challenge 2 - Cognitive Systems, Interaction, Robotics\u27\u27, grant agreement No. ICTIP- 231722

Empirical experiments on intrinsic motivations and action acquisition: results, evaluation, and redefinition

This document presents Deliverable D3.2 of the EU-funded Integrated Project "IM-CLeVeR - Intrinsically Motivated Cumulative Learning Versatile Robots", contract n. FP7-ICT-IP-231722.The aims of the deliverable, as given in the original IM-CLEVER proposal were to identify new key empirical phenomena and processes, allowing the design of a second set of experiments. This report covers: (1) novelty detection and discovery of when/what/how of agency in experiments with humans ("joystick experiment") and Parkinson patients. (2) how object properties that stimulate intrinsically motivated interaction and facilitate the acquisition of adaptive knowledge and skills in monkeys and children ("board experiment")

Observations versus assessments of personality: A five-method multi-species study reveals numerous biases in ratings and methodological limitations of standardised assessments

Personality assessments and observations were contrasted by applying a philosophy-ofscience paradigm and a study of 49 human raters and 150 capuchin monkeys. Twenty constructs were operationalised with 146 behavioural measurements in 17 situations to study capuchins’ individual-specific behaviours and with assessments on trait-adjective and behaviour-descriptive verb items to study raters’ pertinent mental representations. Analyses of reliability, cross-method coherence, taxonomic structures and socio-demographic associations highlighted substantial biases in assessments. Deviations from observations are located in human impression formation, stereotypical biases and the findings that raters interpret standardised items differently and that assessments cannot generate scientific quantifications or capture behaviour. These issues have important implications for the interpretation of findings from assessments and provide an explanation for their frequent lack of replicability