When and Why Do Territorial Coalitions Occur? Experimental Evidence from a Fiddler Crab

  title={When and Why Do Territorial Coalitions Occur? Experimental Evidence from a Fiddler Crab},
  author={Tanya Detto and Michael D. Jennions and Patricia Ruth Yvonne Backwell},
  journal={The American Naturalist},
  pages={E119 - E125}
Neighboring territory owners are often less aggressive toward each other than to strangers (“dear enemy” effect). There is, however, little evidence for territorial defense coalitions whereby a neighbor will temporarily leave his/her own territory, enter that of a neighbor, and cooperate in repelling a conspecific intruder. This is surprising, as theoreticians have long posited the existence of such coalitions and the circumstances under which they should evolve. Here we document territorial… 
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