Honesty in signalling games is maintained by trade-offs rather than costs

BMC Biology

Research Article

Dustin J. Penn¹  Szabolcs Számadó²  István Zachar³  Dániel Czégel⁴ 

[1] Department of Interdisciplinary Life Sciences, Konrad Lorenz Institute of Ethology, University of Veterinary Medicine, Vienna, Savoynestrasse 1a, 1160, Vienna, Austria;Department of Sociology and Communication, Budapest University of Technology and Economics, Egry J. u. 1, H-1111, Budapest, Hungary;CSS-RECENS “Lendület” Research Group, MTA Centre for Social Science, Tóth Kálmán u. 4, H-1097, Budapest, Hungary;Institute of Evolution, MTA Centre for Ecological Research, Konkoly-Thege Miklós út 29-33, H-1121, Budapest, Hungary;Department of Plant Systematics, Ecology and Theoretical Biology, Biology Institute, ELTE University, Pázmány P. sétány 1/C, 1117, Budapest, Hungary;Institute of Evolution, MTA Centre for Ecological Research, Konkoly-Thege Miklós út 29-33, H-1121, Budapest, Hungary;Department of Plant Systematics, Ecology and Theoretical Biology, Biology Institute, ELTE University, Pázmány P. sétány 1/C, 1117, Budapest, Hungary;Doctoral School of Biology, Institute of Biology, Eötvös Loránd University, Pázmány Péter sétány 1/C, H-1117, Budapest, Hungary;BEYOND Center for Fundamental Concepts in Science, Arizona State University, AZ 85287–0506, Tempe, AZ, USA;

关键词: Animal communication;    Honest signals;    Handicap Principle;    Costly signalling theory;    Life-history models;    Trade-offs;    Evolutionary stability;   

DOI  :  10.1186/s12915-022-01496-9

 received in 2022-06-20, accepted in 2022-12-06,  发布年份 2022

来源: Springer

【 摘 要 】

BackgroundSignal reliability poses a central problem for explaining the evolution of communication. According to Zahavi’s Handicap Principle, signals are honest only if they are costly at the evolutionary equilibrium; otherwise, deception becomes common and communication breaks down. Theoretical signalling games have proved to be useful for understanding the logic of signalling interactions. Theoretical evaluations of the Handicap Principle are difficult, however, because finding the equilibrium cost function in such signalling games is notoriously complicated. Here, we provide a general solution to this problem and show how cost functions can be calculated for any arbitrary, pairwise asymmetric signalling game at the evolutionary equilibrium.ResultsOur model clarifies the relationship between signalling costs at equilibrium and the conditions for reliable signalling. It shows that these two terms are independent in both additive and multiplicative models, and that the cost of signalling at honest equilibrium has no effect on the stability of communication. Moreover, it demonstrates that honest signals at the equilibrium can have any cost value, even negative, being beneficial for the signaller independently of the receiver’s response at equilibrium and without requiring further constraints. Our results are general and we show how they apply to seminal signalling models, including Grafen’s model of sexual selection and Godfray’s model of parent-offspring communication.ConclusionsOur results refute the claim that signals must be costly at the evolutionary equilibrium to be reliable, as predicted by the Handicap Principle and so-called ‘costly signalling’ theory. Thus, our results raise serious concerns about the handicap paradigm. We argue that the evolution of reliable signalling is better understood within a Darwinian life-history framework, and that the conditions for honest signalling are more clearly stated and understood by evaluating their trade-offs rather than their costs per se. We discuss potential shortcomings of equilibrium models and we provide testable predictions to help advance the field and establish a better explanation for honest signals. Last but not least, our results highlight why signals are expected to be efficient rather than wasteful.

【 授权许可】

CC BY   
© The Author(s) 2023

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