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Philosophical Transactions of the Royal Society B: Biological Sciences logoLink to Philosophical Transactions of the Royal Society B: Biological Sciences
. 2002 Nov 29;357(1427):1595–1606. doi: 10.1098/rstb.2002.1068

Separating equilibria in continuous signalling games.

Carl T Bergstrom 1, Szabolcs Számadó 1, Michael Lachmann 1
PMCID: PMC1693066  PMID: 12495516

Abstract

Much of the literature on costly signalling theory concentrates on separating equilibria of continuous signalling games. At such equilibria, every signaller sends a distinct signal, and signal receivers are able to exactly infer the signaller's condition from the signal sent. In this paper, we introduce a vector-field solution method that simplifies the process of solving for separating equilibria. Using this approach, we show that continuous signalling games can have low-cost separating equilibria despite conflicting interests between signaller and receiver. We find that contrary to prior arguments, honesty does not require wasteful signals. Finally, we examine signalling games in which different signallers have different minimal-cost signals, and provide a mathematical justification for the argument that even non-signalling traits will be exaggerated beyond their phenotypic optimum when they are used by other individuals to judge condition or quality.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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