Stable individual differences in separation calls during early development in cats and mice

Area of Science:

• Ethology
• Animal Behavior
• Developmental Psychology

Background:

• Studying the origins of animal personality requires ethologically relevant tests in young animals.
• Offspring separation calls are crucial for mother-offspring communication and survival, and linked to emotional state.

Purpose of the Study:

• To investigate consistent individual differences in behavior by integrating offspring separation calls in domestic cats and mound-building mice.
• To explore the ontogeny of animal personality traits using vocalizations as a behavioral indicator.

Main Methods:

• Observing and measuring individual responses, including vocalizations (separation calls) and locomotor activity, in young domestic cats and mound-building mice during brief separation from mother and littermates.
• Assessing the repeatability of these behavioral responses across different ages and among litter siblings.

Main Results:

• Both species exhibited repeatable individual differences in separation call frequency and, to a lesser extent, locomotor activity, indicating personality consistency.
• Individual vocalization and activity patterns were uncorrelated, suggesting they represent distinct personality domains.
• Similar patterns of individual responses were observed in both species, highlighting conserved mechanisms in early personality development.

Conclusions:

• Brief separation tests, especially measuring separation calls, offer a promising avenue for studying the ontogeny of personality traits in young mammals.
• Further long-term research is necessary to link these early personality traits to later-life behaviors.