The Evolution of Animal Weapons

  title={The Evolution of Animal Weapons},
  author={Douglas J. Emlen},
  journal={Annual Review of Ecology, Evolution, and Systematics},
  • D. Emlen
  • Published 31 October 2008
  • Biology
  • Annual Review of Ecology, Evolution, and Systematics
Males in many species invest substantially in structures that are used in combat with rivals over access to females. These weapons can attain extreme proportions and have diversified in form repeatedly. I review empirical literature on the function and evolution of sexually selected weapons to clarify important unanswered questions for future research. Despite their many shapes and sizes, and the multitude of habitats within which they function, animal weapons share many properties: They evolve… 

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