Collective self-assessment in banded mongoose intergroup contests

Area of Science:

• Behavioral Ecology
• Animal Behavior
• Evolutionary Biology

Background:

• Resource contests are common in nature, driving conflict escalation strategies in animals.
• While one-on-one (dyadic) conflict assessment is well-studied, group-level (intergroup) assessment strategies are poorly understood.
• Mutual assessment is often assumed for intergroup conflicts, but empirical evidence is scarce.

Purpose of the Study:

• To investigate the assessment strategies used by animal groups during intergroup contests.
• To test the prevailing assumption of mutual assessment in intergroup conflicts.
• To determine whether self-assessment or mutual assessment better explains conflict escalation in banded mongooses.

Main Methods:

• Utilized a 21-year dataset of 633 intergroup contests in a wild banded mongoose (Mungos mungo) population in Uganda.
• Analyzed contest data to evaluate predictions from self-assessment and mutual assessment models.
• Focused on group size and rival group strength as key variables influencing escalation decisions.

Main Results:

• Results strongly support a self-assessment model for intergroup conflicts in banded mongooses.
• Groups with more males were more likely to escalate conflicts, irrespective of the rival group's strength.
• This contrasts with the common assumption that intergroup conflict decisions rely on mutual assessment.

Conclusions:

• Banded mongoose groups appear to rely on self-assessment rather than mutual assessment when deciding to escalate intergroup conflicts.
• Assessing rival group strength may be too costly or difficult during active conflict compared to assessing own group strength.
• Understanding these assessment dynamics is crucial for explaining intergroup conflict escalation across social species.