Research on primate personality and social relationships




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The Transdisciplinary Philosophy-of-Science Paradigm for Research on Individuals (TPS-Paradigm)

Theoretical, metatheoretical and methodological papers (TPS-Paradigm)

Empirical studies in nonhuman primates (great apes, macaques, mandrills, capuchins)

Personality questionnaires for nonhuman primates

Personality inventories for nonhuman primate species

Theoretical and methodological background
All our personality inventories were developed by applying the Behavioural Repertoire x Behavioural Situations Approach (BRxBS-Approach), a methodological approach that allows for generating "personality" constructs systematically on the basis of the existing scientific literature about the behavioural repertoire of a study species unconcerned with individual differences. For this reason, the constructs and questionnaire items are much less colloquial than those used in questionnaires derived from nominations or human personality inventories (e.g., the Five Factor Model) most of which are rooted in human everyday language. This meets efforts to reduce the impact of implicit meanings contained in everyday language and of anthropomorphic biases.

Quality criteria 
All our inventories have been systematically analysed for their quality criteria, such as inter-rater reliability and test-retest reliability. A vital element is the detailed exploration of the ways in which assessments obtained with our inventories are empirically related to comprehensive behavioural measurements obtained in lab-based tests and group observations. 

Two different formats: Trait-adjective items and behaviour-descriptive verb items
Most inventories are available in two different formats, trait-adjective items and behaviour-descriptive verb items. Although assessments on the two formats show substantial interrelations, thus supporting their validity for capturing people's knowledge about the individuals under study, their properties and relations to observable behaviours are somewhat different. Details and findings about each given inventory are provided in the respective publications of each inventory (see below).

Interpretation of findings from ratings
Any kinds of assessments - because they are based on memory - reflect the knowledge, beliefs and opinions of the persons providing judgements about an individual. But ratings cannot capture how the individuals that are being assessed have actually behaved. Moreover, assessments can generate only subjective quantifications that are essentially different from the scientific quantifications that can be obtained with observational methods. These points are often overlooked in "personality" research. In our line of research, we have systematically explored the differences of behavioural observations versus assessments - both methodologically and empirically

Our studies demonstrated that people's judgements (e.g., of keepers, students and researchers) about individuals of various primate species show substantial coherence to observable individual behaviours. But assessments also contain numerous biases that derive from the mental processes of human impression formation. For example, by abstracting information from many observations over time, people oversimplify the complex patterns that can be observed in behaviour and therefore overestimate the temporal stability and cross-situational consistency of individuals' behaviour. Further biases seem to be related to stereotypical beliefs, such as about differences between individuals of different age, sex and social status (Uher & Asendorpf, 2008; Uher & Visalberghi, 2016; Uher, Werner & Gosselt, 2013). 

Exploring the judgements of people who are well familiar with primate individuals is nevertheless important and informative because people who are dealing with primates on an everyday basis, such as caretakers and researchers, successfully use their knowledge about primate individuals for making decisions in captive management. Assessments provide easy and quick tools to collect some first information about the knowledge and impressions that some persons (e.g., keepers) have developed about an individual on the basis of their previous experiences with that individual.

Please do not hesitate to contact us for any questions and comments you may have. We are happy to hear from you and your findings and to read your publications. 


GAPI - Great Ape Personality Inventory

The GAPI is a standardised tool for assessments of captive Great Ape individuals (chimpanzees, bonobos, gorillas and orangutans). It consists of 17 trait-adjective items and 34 behaviour-descriptive verb items. Assessments are indicated on either a five-point agreement scale (Likert scale) or a five-point frequency scale.

Publications about the GAPI and relations of the assessments to behavioural tests and observations

Publication about the 14 behavioural tests and 2 group observations used for cross-method comparisons


MPIc - Macaque Personality Inventory (for captive individuals)

The MPIc is a standardised tool for assessments of captive macaque individuals. It consists of 18 trait-adjective items and 30 behaviour-descriptive verb items. Assessments are indicated on a five-point frequency scale.
Publication about the MPIc and relations of the assessments to behavioural observations


CPI - Capuchin Personality Inventory

The CPI is a standardised tool for assessments of captive capuchin monkey individuals. It consists of 21 trait-adjective items and 34 behaviour-descriptive verb items. Assessments are indicated on a five-point frequency scale.
Publication about the CPI and relations of the assessments to behavioural observations


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