Consistent inter-individual differences in common marmosets (Callithrix jacchus) in Boldness-Shyness,...

Area of Science:

• Animal behavior
• Primatology
• Behavioral ecology

Background:

• Animal personality is a rapidly expanding field in biology.
• Non-human primates are increasingly studied, but often assessed via questionnaires rather than standardized experiments.
• Consistent behavioral differences are key to understanding animal personality.

Purpose of the Study:

• To investigate personality consistency in common marmosets (Callithrix jacchus) across time and contexts.
• To identify major non-social personality components in this species.
• To explore potential group-level personality differences.

Main Methods:

• Twenty-one common marmosets from three family groups were tested in five standardized behavioral experiments and controls.
• Behavioral data were analyzed for consistency over time and across different experimental contexts.
• Statistical analyses were used to identify personality components and group differences.

Main Results:

• Behavioral differences among marmosets were consistent over time and across contexts.
• Four major non-social personality components were identified: Boldness-Shyness in Foraging, Boldness-Shyness in Predation, Stress-Activity, and Exploration-Avoidance.
• No significant sex or age differences were found, but Exploration-Avoidance varied between family groups.

Conclusions:

• Common marmosets exhibit stable, context-independent personality traits.
• The observed variation in Exploration-Avoidance suggests potential "group personality" within family groups.
• These findings contribute to understanding primate personality and social influences on behavior.