Cost and conflict in animal signals and human language

  title={Cost and conflict in animal signals and human language},
  author={Michael Lachmann and Szabolcs Sz{\'a}mad{\'o} and Carl T. Bergstrom},
  journal={Proceedings of the National Academy of Sciences of the United States of America},
  pages={13189 - 13194}
The “costly signaling” hypothesis proposes that animal signals are kept honest by appropriate signal costs. We show that to the contrary, signal cost is unnecessary for honest signaling even when interests conflict. We illustrate this principle by constructing examples of cost-free signaling equilibria for the two paradigmatic signaling games of Grafen (1990) and Godfray (1991). Our findings may explain why some animal signals use cost to ensure honesty whereas others do not and suggest that… 

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