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The Role of Sex in Structuring Aggression, Rank, and Hierarchy in Monk Parakeets
Yuchen Chen1, Sara E Lipshutz1, Elizabeth A Hobson2
1Department of Biology, Duke University, Durham, NC 27708, USA.
Integrative and Comparative Biology
|July 1, 2026
Summary
In monk parakeets, this study found that sex had limited impact on aggression and social rank within mixed-sex groups. Both male and female birds exhibited similar levels of aggression and dominance, challenging assumptions of sex-specific social dynamics.
Area of Science:
- Ethology
- Behavioral Ecology
- Animal Social Dynamics
Background:
- Aggressive interactions are crucial for establishing social rank and dominance hierarchies in gregarious species.
- Traditional research often analyzes aggression and dominance separately for males and females, assuming different selection pressures.
- Limited research directly compares sex roles in aggression and dominance within mixed-sex social environments.
Purpose of the Study:
- To investigate the influence of sex on aggression levels, target selection, and dominance hierarchy establishment in monk parakeets (Myiopsitta monachus).
- To determine if sex predicts aggressiveness, the choice of aggression targets, and the social rank achieved in captive, mixed-sex groups.
- To provide insights into sex similarities and differences in social aggression and dominance within complex social structures.
Main Methods:
- Studied captive, mixed-sex groups of monk parakeets (5 groups, 10 individuals each).
- Compared aggression levels, choice of aggression targets, and dominance hierarchies between sexes at individual, dyadic, and group levels.
- Analyzed whether an individual's sex predicted their aggressiveness, target choice, and social rank.
Main Results:
- No significant difference in aggression levels was found between males and females.
- Sex did not significantly impact the target choice during aggressive interactions.
- An individual's sex did not significantly predict their social rank; males and females were equally likely to achieve high ranks.
Conclusions:
- Sex has limited influence on aggression and social rank in mixed-sex groups of monk parakeets.
- Findings suggest that social selection pressures may affect sexes similarly in this species.
- Highlights the importance of studying both sexes together in social dynamics research to understand complex social environments.
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