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Evidence for tactical concealment in a wild primate
Aliza le Roux1, Noah Snyder-Mackler, Eila K Roberts
1Department of Zoology and Entomology, University of the Free State Qwaqwa, Phuthaditjhaba 9866, South Africa.
Nature Communications
|February 14, 2013
Summary
Wild geladas (Theropithecus gelada) display deceptive behaviors during extra-pair copulations to avoid detection. This study provides rare empirical evidence of both tactical deception and punishment in a primate reproductive context.
Area of Science:
- Primate behavior
- Evolutionary biology
- Animal communication
Background:
- Deceptive behaviors and punishment are predicted by theory but rarely observed in nature.
- Empirical data on deception and punishment, especially in primates, is scarce.
- Understanding these behaviors is crucial for evolutionary studies.
Purpose of the Study:
- To quantify deception and punishment in wild geladas during reproduction.
- To investigate the occurrence of tactical concealment and retaliatory aggression.
- To establish a model system for studying the co-evolution of deception and punishment.
Main Methods:
- Observing wild gelada (Theropithecus gelada) populations.
- Quantifying behaviors during extra-pair copulations.
- Analyzing vocalizations and proximity of males during copulations.
Main Results:
- Individuals engaged in extra-pair copulations showed reduced vocalization and copulated when the cuckolded male was distant (>20m).
- Approximately 20% of extra-pair copulations resulted in post-copulatory aggression from cuckolded males, indicative of punishment.
- This study provides rare empirical evidence of both tactical deception and punishment in a natural setting.
Conclusions:
- Wild geladas exhibit tactical deception in reproductive contexts.
- Post-copulatory aggression in geladas serves as a form of punishment.
- Geladas offer a valuable model for studying the interplay of deception and punishment in evolution.
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