Editing Handicap principle (section)

=== Cheap talk models without handicaps ===

{{further|Cheap talk}}

Counter-examples to handicap models predate handicap models themselves. Models of signals (such as [[Deimatic behaviour|threat displays]]) without any handicapping costs show that what biologists call [[cheap talk]] may be an evolutionarily stable form of communication.<ref>{{cite journal |last=Enquist |first=M. |year=1985 |title=Communication during aggressive interactions with particular reference to variation in choice of behaviour |journal=Animal Behaviour |volume=33 |issue=4 |pages=1152–1161 |doi=10.1016/S0003-3472(85)80175-5 |s2cid=53200843 }}</ref> Analysis of some begging models shows that non-communication strategies are not only evolutionarily stable, but lead to higher payoffs for both players.<ref>{{cite journal |last1=Rodriguez-Girones |first1=M. A. |last2=Cotton |first2=P. A. |last3=Kacelnik |first3=A. |year=1996 |title=The evolution of begging: signaling and sibling competition |journal=[[Proceedings of the National Academy of Sciences of the United States of America]] |volume=93 |issue=25 |pages=14637–14641 |doi=10.1073/pnas.93.25.14637|pmid=8962106 |pmc=26187 |bibcode=1996PNAS...9314637R |doi-access=free }}</ref><ref>{{cite journal |last1=Lachmann |first1=M. |author-link2=Carl Bergstrom |last2=Bergstrom |first2=C. T. |year=1998 |title=Signalling among relatives. II. Beyond the tower of babel |journal=Theoretical Population Biology |volume=54 |issue=2 |pages=146–160 |doi=10.1006/tpbi.1997.1372 |pmid=9733656|doi-access=free |bibcode=1998TPBio..54..146L }}</ref> In human [[mate choice]], mathematical analyses including [[Monte Carlo method|Monte Carlo simulations]] suggest that costly traits ought to be more attractive to the other sex and much rarer than non-costly traits.<ref>{{cite journal |last=Kock |first=N. |year=2011 |url=http://cits.tamiu.edu/kock/Pubs/journals/2011JournalJEP/Kock_2011_JEP_EvoMateChTrts.pdf |title=A mathematical analysis of the evolution of human mate choice traits: Implications for evolutionary psychologists |journal=Journal of Evolutionary Psychology |volume=9 |issue=3 |pages=219–247 |doi=10.1556/jep.9.2011.3.1}}</ref>

It was soon discovered that honest signals need not be costly at the honest equilibrium, even under conflict of interest. This conclusion was first shown in [[Discrete modelling|discrete models]]<ref>{{Cite journal |last=Hurd |first=Peter L. |date=May 1995 |title=Communication in discrete action-response games |url=http://dx.doi.org/10.1006/jtbi.1995.0093 |journal=Journal of Theoretical Biology |volume=174 |issue=2 |pages=217–222 |doi=10.1006/jtbi.1995.0093 |bibcode=1995JThBi.174..217H |issn=0022-5193|url-access=subscription }}</ref><ref>{{Cite journal |last=Számadó |first=Szabolcs |date=June 1999 |title=The Validity of the Handicap Principle in Discrete Action–Response Games |url=http://dx.doi.org/10.1006/jtbi.1999.0935 |journal=Journal of Theoretical Biology |volume=198 |issue=4 |pages=593–602 |doi=10.1006/jtbi.1999.0935 |pmid=10373357 |bibcode=1999JThBi.198..593S |issn=0022-5193|url-access=subscription }}</ref> and then in [[Continuous modelling|continuous models]].<ref>{{Cite journal |last1=Lachmann |first1=Michael |last2=Számadó |first2=Szabolcs |last3=Bergstrom |first3=Carl T. |date=2001-10-30 |title=Cost and conflict in animal signals and human language |journal=Proceedings of the National Academy of Sciences |volume=98 |issue=23 |pages=13189–13194 |doi=10.1073/pnas.231216498 |pmid=11687618 |issn=0027-8424|pmc=60846 |doi-access=free |bibcode=2001PNAS...9813189L }}</ref><ref>{{Cite journal |last1=Számadó |first1=Szabolcs |last2=Czégel |first2=Dániel |last3=Zachar |first3=István |date=2017-12-28 |title=One problem, too many solutions: How costly is honest signalling of need? |journal=PLOS ONE |volume=14 |issue=1 |pages=e0208443 |doi=10.1371/journal.pone.0208443|doi-access=free |biorxiv=10.1101/240440 |pmid=30633748 |pmc=6329501 }}</ref><ref>{{Cite journal |last1=Számadó |first1=Szabolcs |last2=Zachar |first2=István |last3=Czégel |first3=Dániel |last4=Penn |first4=Dustin J. |date=2023-01-08 |title=Honesty in signalling games is maintained by trade-offs rather than costs |journal=BMC Biology |volume=21 |issue=1 |page=4 |doi=10.1186/s12915-022-01496-9 |pmid=36617556 |issn=1741-7007|pmc=9827650 |doi-access=free }}</ref> Similar results were obtained in [[Conflict theories|conflict models]]: threat displays need not be handicaps to be honest and evolutionarily stable.<ref name="Számadó 2003 pp. 327–348">{{cite journal |last=Számadó |first=Szabolcs |title=Threat Displays are not Handicaps |journal=Journal of Theoretical Biology |publisher=Elsevier |volume=221 |issue=3 |year=2003 |issn=0022-5193 |doi=10.1006/jtbi.2003.3176 |pages=327–348|pmid=12642112 |bibcode=2003JThBi.221..327S }}</ref>