@article{MTMT:34767072,
title = {Cue-driven microbial cooperation and communication: evolving quorum sensing with honest signaling},
url = {https://m2.mtmt.hu/api/publication/34767072},
author = {Czárán, Tamás and Scheuring, István and Zachar, István and Számadó, Szabolcs},
doi = {10.1186/s12915-024-01857-6},
journal-iso = {BMC BIOL},
journal = {BMC BIOLOGY},
volume = {22},
unique-id = {34767072},
issn = {1741-7007},
abstract = {Quorum sensing (QS) is the ability of microorganisms to assess local clonal density by measuring the extracellular concentration of signal molecules that they produce and excrete. QS is also the only known way of bacterial communication that supports the coordination of within-clone cooperative actions requiring a certain threshold density of cooperating cells. Cooperation aided by QS communication is sensitive to cheating in two different ways: laggards may benefit from not investing in cooperation but enjoying the benefit provided by their cooperating neighbors, whereas Liars explicitly promise cooperation but fail to do so, thereby convincing potential cooperating neighbors to help them, for almost free. Given this double vulnerability to cheats, it is not trivial why QS-supported cooperation is so widespread among prokaryotes.},
year = {2024},
eissn = {1741-7007},
orcid-numbers = {Czárán, Tamás/0000-0002-2722-6208; Scheuring, István/0000-0002-8108-8897; Zachar, István/0000-0002-3505-0628; Számadó, Szabolcs/0000-0003-2204-9705}
}
@article{MTMT:35425884,
title = {Tautology explains evolution without variation and selection. A Comment on: 'An evolutionary process without variation and selection' (2021), by Gabora et al.},
url = {https://m2.mtmt.hu/api/publication/35425884},
author = {Zachar, István and Máté, Jakab and Számadó, Szabolcs},
doi = {10.1098/rsif.2023.0579},
journal-iso = {J R SOC INTERFACE},
journal = {JOURNAL OF THE ROYAL SOCIETY INTERFACE},
volume = {21},
unique-id = {35425884},
issn = {1742-5689},
abstract = {Gabora and Steel (Gabora L, Steel M. 2021 An evolutionary process without variation and selection. J. R. Soc. Interface 18, 20210334. [doi:10.1098/rsif.2021.0334]) claim that cumulative adaptive evolution is possible without natural selection, that is, without variation and competition. To support this claim, the authors modelled a theoretical process called self-other reorganization (SOR) that envisages a population of reflexively autocatalytic sets that can accumulate beneficial changes without any form of birth, death or selection, that is without population dynamics. The authors claim that despite being non-Darwinian, adaptive evolution happens in SOR, deeming it relevant to the origin of life and to cultural evolution. We analysed SOR and the claim that it implements evolution without variation and selection. We found that the authors, by design, ignore the growth and/or degradation of autocatalytic sets or their components, assuming all effects are beneficial and all entities in SOR are identical and immutable. We prove that due to these assumptions, SOR is a trivial model of horizontal percolation of beneficial effects over a static population. We implemented an extended model of SOR including more realistic assumptions to prove that accounting for any of the ignored processes inevitably leads to conventional Darwinian dynamics. Our analysis directly challenges the authors' claims, revealing evidence of an overly fragile foundation. While the best-case scenario the authors incorrectly generalize from may be mathematically valid, stripping away their unrealistic assumptions reveals that SOR does not represent real entities (e.g. protocells) but rather models the triviality that fast horizontal diffusion of effects can effectively equalize a population. Adaptation in SOR is solely because the authors only consider beneficial effects. The omission of death/growth dynamics and maladaptive effects renders SOR unrealistic and its relevance to evolution, cultural or biological, questionable.},
keywords = {EVOLUTION; ADAPTATION; PERCOLATION; population dynamics; INHERITANCE; Darwinian dynamics},
year = {2024},
eissn = {1742-5662},
orcid-numbers = {Zachar, István/0000-0002-3505-0628; Számadó, Szabolcs/0000-0003-2204-9705}
}
@article{MTMT:33549897,
title = {Honesty in signalling games is maintained by trade-offs rather than costs},
url = {https://m2.mtmt.hu/api/publication/33549897},
author = {Számadó, Szabolcs and Zachar, István and Czégel, Dániel and Dustin J., Penn},
doi = {10.1186/s12915-022-01496-9},
journal-iso = {BMC BIOL},
journal = {BMC BIOLOGY},
volume = {21},
unique-id = {33549897},
issn = {1741-7007},
abstract = {Background Signal 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 use- ful 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. Results Our 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 inde- pendently 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. Conclusions Our 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 Darwin- ian 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.},
year = {2023},
eissn = {1741-7007},
orcid-numbers = {Számadó, Szabolcs/0000-0003-2204-9705; Zachar, István/0000-0002-3505-0628}
}
@article{MTMT:32638620,
title = {Four Puzzles of Reputation-Based Cooperation: Content, Process, Honesty, and Structure},
url = {https://m2.mtmt.hu/api/publication/32638620},
author = {Giardini, Francesca and Balliet, Daniel and Power, Eleanor A. and Számadó, Szabolcs and Takács, Károly},
doi = {10.1007/s12110-021-09419-3},
journal-iso = {HUM NAT-INT BIOS},
journal = {HUMAN NATURE-AN INTERDISCIPLINARY BIOSOCIAL PERSPECTIVE},
volume = {33},
unique-id = {32638620},
issn = {1045-6767},
abstract = {Research in various disciplines has highlighted that humans are uniquely able to solve the problem of cooperation through the informal mechanisms of reputation and gossip. Reputation coordinates the evaluative judgments of individuals about one another. Direct observation of actions and communication are the essential routes that are used to establish and update reputations. In large groups, where opportunities for direct observation are limited, gossip becomes an important channel to share individual perceptions and evaluations of others that can be used to condition cooperative action. Although reputation and gossip might consequently support large-scale human cooperation, four puzzles need to be resolved to understand the operation of reputation-based mechanisms. First, we need empirical evidence of the processes and content that form reputations and how this may vary cross-culturally. Second, we lack an understanding of how reputation is determined from the muddle of imperfect, biased inputs people receive. Third, coordination between individuals is only possible if reputation sharing and signaling is to a large extent reliable and valid. Communication, however, is not necessarily honest and reliable, so theoretical and empirical work is needed to understand how gossip and reputation can effectively promote cooperation despite the circulation of dishonest gossip. Fourth, reputation is not constructed in a social vacuum; hence we need a better understanding of the way in which the structure of interactions affects the efficiency of gossip for establishing reputations and fostering cooperation.},
keywords = {EVOLUTION; EVOLUTION; COOPERATION; SEX-DIFFERENCES; anthropology; INDIRECT RECIPROCITY; PARTNER CHOICE; REPUTATION; social information; gossip; gossip; biological markets; PROMOTE COOPERATION; FREE-RIDERS},
year = {2022},
eissn = {1936-4776},
pages = {43-61},
orcid-numbers = {Balliet, Daniel/0000-0001-5365-9675; Power, Eleanor A./0000-0002-3064-2050; Számadó, Szabolcs/0000-0003-2204-9705; Takács, Károly/0000-0001-9126-3233}
}
@article{MTMT:33205038,
title = {Condition-dependent trade-offs maintain honest signalling},
url = {https://m2.mtmt.hu/api/publication/33205038},
author = {Számadó, Szabolcs and Samu, Flóra and Takács, Károly},
doi = {10.1098/rsos.220335},
journal-iso = {R SOC OPEN SCI},
journal = {ROYAL SOCIETY OPEN SCIENCE},
volume = {9},
unique-id = {33205038},
abstract = {How and why animals and humans signal reliably is a key issue in biology and social sciences that needs to be understood to explain the evolution of communication. In situations in which the receiver needs to differentiate between low- and high-quality signallers, once a ruling paradigm, the Handicap Principle has claimed that honest signals have to be costly to produce. Subsequent game theoretical models, however, highlighted that honest signals are not necessarily costly. Honesty is maintained by the potential cost of cheating: by the difference in the marginal benefit to marginal cost for low versus high-quality signallers; i.e. by differential trade-offs. Owing to the difficulties of manipulating signal costs and benefits, there is lack of empirical tests of these predictions. We present the results of a laboratory decision-making experiment with human participants to test the role of equilibrium signal cost and signalling trade-offs for the development of honest communication. We found that the trade-off manipulation had a much higher influence on the reliability of communication than the manipulation of the equilibrium cost of signal. Contrary to the predictions of the Handicap Principle, negative production cost promoted honesty at a very high level in the differential trade-off condition.},
keywords = {EVOLUTION; COMMUNICATION; COOPERATION; Sexual selection; cost; Handicap; PREFERENCES; HANDICAP PRINCIPLE; Deception; honest signalling; Costly signalling; Biological signals; condition-dependent trade-offs},
year = {2022},
eissn = {2054-5703},
orcid-numbers = {Számadó, Szabolcs/0000-0003-2204-9705; Takács, Károly/0000-0001-9126-3233}
}
@article{MTMT:32337938,
title = {Cooperating to show that you care: costly helping as an honest signal of fitness interdependence},
url = {https://m2.mtmt.hu/api/publication/32337938},
author = {Barclay, Pat and Bliege Bird, Rebecca and Roberts, Gilbert and Számadó, Szabolcs},
doi = {10.1098/rstb.2020.0292},
journal-iso = {PHILOS T ROY SOC B},
journal = {PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY B - BIOLOGICAL SCIENCES},
volume = {376},
unique-id = {32337938},
issn = {0962-8436},
year = {2021},
eissn = {1471-2970},
orcid-numbers = {Roberts, Gilbert/0000-0001-5954-3243; Számadó, Szabolcs/0000-0003-2204-9705}
}
@article{MTMT:32286117,
title = {The language of cooperation: reputation and honest signalling},
url = {https://m2.mtmt.hu/api/publication/32286117},
author = {Számadó, Szabolcs and Balliet, D. and Giardini, F. and Power, E. A. and Takács, Károly},
doi = {10.1098/rstb.2020.0286},
journal-iso = {PHILOS T ROY SOC B},
journal = {PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY B - BIOLOGICAL SCIENCES},
volume = {376},
unique-id = {32286117},
issn = {0962-8436},
year = {2021},
eissn = {1471-2970},
orcid-numbers = {Számadó, Szabolcs/0000-0003-2204-9705; Balliet, D./0000-0001-5365-9675; Giardini, F./0000-0001-7512-0048; Power, E. A./0000-0002-3064-2050; Takács, Károly/0000-0001-9126-3233}
}
@article{MTMT:32289861,
title = {Pre-hunt charade as the cradle of human musicality},
url = {https://m2.mtmt.hu/api/publication/32289861},
author = {Számadó, Szabolcs},
doi = {10.1017/S0140525X20001077},
journal-iso = {BEHAV BRAIN SCI},
journal = {BEHAVIORAL AND BRAIN SCIENCES},
volume = {44},
unique-id = {32289861},
issn = {0140-525X},
abstract = {Human language and human music are both unique communication systems that evolved in the human lineage. Here, I propose that they share the same root, they evolved from an ancestral communication system yet to be described in detail. I suggest that pre-hunt charade was this shared root, which helped organize and coordinate the hunt of early hominins.},
year = {2021},
eissn = {1469-1825},
orcid-numbers = {Számadó, Szabolcs/0000-0003-2204-9705}
}
@article{MTMT:32351234,
title = {Honesty and dishonesty in gossip strategies: a fitness interdependence analysis},
url = {https://m2.mtmt.hu/api/publication/32351234},
author = {Wu, Junhui and Számadó, Szabolcs and Barclay, Pat and Beersma, Bianca and Cruz, Terence D. Dores and Lo Iacono, Sergio and Nieper, Annika S. and Peters, Kim and Przepiorka, Wojtek and Tiokhin, Leo and Van Lange, Paul A. M.},
doi = {10.1098/rstb.2020.0300},
journal-iso = {PHILOS T ROY SOC B},
journal = {PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY B - BIOLOGICAL SCIENCES},
volume = {376},
unique-id = {32351234},
issn = {0962-8436},
abstract = {Gossip, or sharing information about absent others, has been identified as an effective solution to free rider problems in situations with conflicting interests. Yet, the information transmitted via gossip can be biased, because gossipers may send dishonest information about others for personal gains. Such dishonest gossip makes reputation-based cooperation more difficult to evolve. But when are people likely to share honest or dishonest gossip? We build formal models to provide the theoretical foundation for individuals' gossip strategies, taking into account the gossiper's fitness interdependence with the receiver and the target. Our models across four different games suggest a very simple rule: when there is a perfect match (mismatch) between fitness interdependence and the effect of honest gossip, the gossiper should always be honest (dishonest); however, in the case of a partial match, the gossiper should make a choice based on their fitness interdependence with the receiver and the target and the marginal cost/benefit in terms of pay-off differences caused by possible choices of the receiver and the target in the game. Moreover, gossipers can use this simple rule to make optimal decisions even under noise. We discuss empirical examples that support the predictions of our model and potential extensions. This article is part of the theme issue 'The language of cooperation: reputation and honest signalling'.},
keywords = {COOPERATION; modelling approach; REPUTATION; dishonest gossip; fitness interdependence},
year = {2021},
eissn = {1471-2970},
orcid-numbers = {Számadó, Szabolcs/0000-0003-2204-9705}
}
@techreport{MTMT:31678956,
title = {Cheating in primary school. experimental evidence on egodepletion and individual factors},
url = {https://m2.mtmt.hu/api/publication/31678956},
author = {Keller, Tamás and Kiss, Hubert János and Számadó, Szabolcs},
unique-id = {31678956},
year = {2020},
orcid-numbers = {Kiss, Hubert János/0000-0003-3666-9331; Számadó, Szabolcs/0000-0003-2204-9705}
}