Evolutionary Ecology

, Volume 17, Issue 5–6, pp 509–522 | Cite as

The Napoleon Complex: why smaller males pick fights

  • Winfried JustEmail author
  • Molly R. Morris


Does it ever pay for smaller animals to initiate fights even when they are likely to lose? Asymmetry in payoffs between opponents or a suboptimal strategy resulting from likely losers misperceiving themselves as likely winners have both been proposed as possible explanations for the aggressive behavior of smaller males. The model presented here suggests that in some cases, even without a payoff asymmetry and allowing for only a small error in perception, likely losers are expected to attack first. If the value of the resource exceeds the cost of losing a fight, the cost of displaying is sufficiently small, and assessment of resource holding power is reasonably accurate but not perfect, the evolutionarily stable strategy (ESS) prompts those contestants who perceive themselves as the likely losers to initiate fights, while it prompts those contestants who perceive themselves as the likely winners to wait for the adversary to attack or retreat.

aggression assessment of fighting ability escalation evolutionarily stable strategy resource holding power 


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© Kluwer Academic Publishers 2003

Authors and Affiliations

  1. 1.Department of MathematicsOhio UniversityAthensUSA
  2. 2.Department of Biological SciencesOhio UniversityAthensUSA

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