The Evolution of Reciprocal Altruism
Abstract
A model is presented to account for the natural selection of what is termed reciprocally altruistic behavior. The model shows how selection can operate against the cheater (non-reciprocator) in the system. Three instances of altruistic behavior are discussed, the evolution of which the model can explain: (1) behavior involved in cleaning symbioses; (2) warning cries in birds; and (3) human reciprocal altruism. Regarding human reciprocal altruism, it is shown that the details of the psychological system that regulates this altruism can be explained by the model. Specifically, friendship, dislike, moralistic aggression, gratitude, sympathy, trust, suspicion, trustworthiness, aspects of guilt, and some forms of dishonesty and hypocrisy can be explained as important adaptations to regulate the altruistic system. Each individual human is seen as possessing altruistic and cheating tendencies, the expression of which is sensitive to developmental variables that were selected to set the tendencies at a balance appropriate to the local social and ecological environment.
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This orientation towards relational repair echoes the logic of reciprocal altruism.
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Evolutionary theories emphasize kinship and reciprocity in helping.
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From Volunteerism as a multidimensional form of human prosocial engagement (2026) · cites this paper as [43]
Cites
The norm of reciprocity: A preliminary statement
Gouldner, A. W. (1960) · American Sociological Review · doi:10.2307/2092623 · Cited by 12,001 · see citing works
Deutsch, M. (1958) · Journal of Conflict Resolution · doi:10.1177/002200275800200401 · Cited by 2,077 · see citing works
Flagged first, then by citations
Cited by
Sorted by citations
Axelrod, R., & Hamilton, W. D. (1981) · Science · doi:10.1126/science.7466396 · Cited by 20,065 · see citing works
Possessions and the Extended Self
Belk, R. W. (1988) · Journal of Consumer Research · doi:10.1086/209154 · Cited by 9,064 · see citing works
The emotional dog and its rational tail: A social intuitionist approach to moral judgment.
Haidt, J. (2001) · Psychological Review · doi:10.1037/0033-295x.108.4.814 · Cited by 8,048 · see citing works
An attributional theory of achievement motivation and emotion
Weiner, B. (1985) · Psychological Review · doi:10.1037/0033-295x.92.4.548 · Cited by 7,846 · see citing works
Five Rules for the Evolution of Cooperation
Nowak, M. A. (2006) · Science · doi:10.1126/science.1133755 · Cited by 5,894 · see citing works
Altruistic punishment in humans
Fehr, E., & Gächter, S. (2002) · Nature · doi:10.1038/415137a · Cited by 5,616 · see citing works
Mate selection—A selection for a handicap
Zahavi, A. (1975) · Journal of Theoretical Biology · doi:10.1016/0022-5193(75)90111-3 · Cited by 5,251 · see citing works
Liberals and conservatives rely on different sets of moral foundations.
Graham, J., Haidt, J., & Nosek, B. A. (2009) · Journal of Personality and Social Psychology · doi:10.1037/a0015141 · Cited by 4,560 · see citing works
Empathy: its ultimate and proximate bases
Preston, S. D., & de Waal, F. B. M. (2002) · Behavioral and Brain Sciences · doi:10.1017/s0140525x02000018 · Cited by 4,126 · see citing works
Collective action and the evolution of social norms.
Ostrom, E. (2000) · Journal of Economic Perspectives · doi:10.1257/jep.14.3.137 · Cited by 4,195 · see citing works
Fehr, E., & Fischbacher, U. (2003) · Nature · doi:10.1038/nature02043 · Cited by 3,475 · see citing works
Pursuing Happiness: The Architecture of Sustainable Change
Lyubomirsky, S., Sheldon, K. M., & Schkade, D. (2005) · Review of General Psychology · doi:10.1037/1089-2680.9.2.111 · Cited by 3,203 · see citing works
Evolution of indirect reciprocity
Nowak, M. A., & Sigmund, K. (2005) · Nature · doi:10.1038/nature04131 · Cited by 2,762 · see citing works
Graham, J., Nosek, B. A., Haidt, J., Iyer, R., Koleva, S., & Ditto, P. H. (2011) · Journal of Personality and Social Psychology · doi:10.1037/a0021847 · Cited by 2,666 · see citing works
The four elementary forms of sociality: Framework for a unified theory of social relations.
Fiske, A. P. (1992) · Psychological Review · doi:10.1037/0033-295x.99.4.689 · Cited by 2,510 · see citing works
Putting the Altruism Back into Altruism: The Evolution of Empathy
de Waal, F. B. M. (2008) · Annual Review of Psychology · doi:10.1146/annurev.psych.59.103006.093625 · Cited by 2,483 · see citing works
Cosmides, L. (1989) · Cognition · doi:10.1016/0010-0277(89)90023-1 · Cited by 2,471 · see citing works
Falk, A., & Fischbacher, U. (2006) · Games and Economic Behavior · doi:10.1016/j.geb.2005.03.001 · Cited by 2,416 · see citing works
The grateful disposition: A conceptual and empirical topography.
McCullough, M. E., Emmons, R. A., & Tsang, J.-A. (2002) · Journal of Personality and Social Psychology · doi:10.1037//0022-3514.82.1.112 · Cited by 3,664 · see citing works
A simple rule for the evolution of cooperation on graphs and social networks
Ohtsuki, H., Hauert, C., Lieberman, E., & Nowak, M. A. (2006) · Nature · doi:10.1038/nature04605 · Cited by 2,208 · see citing works
Compassion: an evolutionary analysis and empirical review
Goetz, J. L., Keltner, D., & Simon-Thomas, E. (2010) · Psychological Bulletin · doi:10.1037/a0018807 · Cited by 2,200 · see citing works
When Morality Opposes Justice: Conservatives Have Moral Intuitions that Liberals may not Recognize
Haidt, J., & Graham, J. (2007) · Social Justice Research · doi:10.1007/s11211-007-0034-z · Cited by 2,385 · see citing works
Going green to be seen: status, reputation, and conspicuous conservation
Griskevicius, V., Tybur, J. M., & Van den Bergh, B. (2010) · Journal of Personality and Social Psychology · doi:10.1037/a0017346 · Cited by 2,174 · see citing works
Empirical, Theoretical, and Practical Advantages of the HEXACO Model of Personality Structure
Ashton, M. C., & Lee, K. (2007) · Personality and Social Psychology Review · doi:10.1177/1088868306294907 · Cited by 2,171 · see citing works
Value orientations, gender and environmental concern
Stern, P. C., Dietz, T., & Kalof, L. (1993) · Environment and Behavior · doi:10.1177/0013916593255002 · Cited by 2,162 · see citing works
Social Norms and Economic Theory
Elster, J. (1989) · Journal of Economic Perspectives · doi:10.1257/jep.3.4.99 · Cited by 2,071 · see citing works
Materialism: Trait Aspects of Living in the Material World
Belk, R. W. (1985) · Journal of Consumer Research · doi:10.1086/208515 · Cited by 1,966 · see citing works
How (and where) does moral judgment work?
Greene, J., & Haidt, J. (2002) · Trends in Cognitive Sciences · doi:10.1016/s1364-6613(02)02011-9 · Cited by 1,945 · see citing works
“Economic man” in cross-cultural perspective: behavioral experiments in 15 small-scale societies
Henrich, J., Boyd, R., Bowles, S., Camerer, C., Fehr, E., Gintis, H., McElreath, R., Alvard, M., Barr, A., Ensminger, J., et al. (2005) · Behavioral and Brain Sciences · doi:10.1017/s0140525x05000142 · Cited by 1,898 · see citing works
Social semantics: altruism, cooperation, mutualism, strong reciprocity and group selection.
WEST, S. A., GRIFFIN, A. S., & GARDNER, A. (2007) · Journal of Evolutionary Biology · doi:10.1111/j.1420-9101.2006.01258.x · Cited by 1,889 · see citing works
The evolution of altruistic punishment
Boyd, R., Gintis, H., Bowles, S., & Richerson, P. J. (2003) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.0630443100 · Cited by 1,748 · see citing works
Cognitive neuroscience of human social behaviour
Adolphs, R. (2003) · Nature Reviews Neuroscience · doi:10.1038/nrn1056 · Cited by 1,657 · see citing works
Social evaluation by preverbal infants
Hamlin, J. K., Wynn, K., & Bloom, P. (2007) · Nature · doi:10.1038/nature06288 · Cited by 1,566 · see citing works
McCullough, M. E., Kilpatrick, S. D., Emmons, R. A., & Larson, D. B. (2001) · Psychological Bulletin · doi:10.1037/0033-2909.127.2.249 · Cited by 1,698 · see citing works
Punishment allows the evolution of cooperation (or anything else) in sizable groups
Boyd, R., & Richerson, P. J. (1992) · Ethology and Sociobiology · doi:10.1016/0162-3095(92)90032-y · Cited by 1,482 · see citing works
Sustaining cooperation in laboratory public goods experiments: a selective survey of the literature
Chaudhuri, A. (2011) · Experimental Economics · doi:10.1007/s10683-010-9257-1 · Cited by 1,445 · see citing works
A neural basis for social cooperation
Rilling, J. K., Gutman, D. A., Zeh, T. R., Pagnoni, G., Berns, G. S., & Kilts, C. D. (2002) · Neuron · doi:10.1016/s0896-6273(02)00755-9 · Cited by 1,451 · see citing works
Getting to Know You: Reputation and Trust in a Two-Person Economic Exchange
King-Casas, B., Tomlin, D., Anen, C., Camerer, C. F., Quartz, S. R., & Montague, P. R. (2005) · Science · doi:10.1126/science.1108062 · Cited by 1,345 · see citing works
Spontaneous giving and calculated greed
Rand, D. G., Greene, J. D., & Nowak, M. A. (2012) · Nature · doi:10.1038/nature11467 · Cited by 1,334 · see citing works
A Darwinian Dilemma for Realist Theories of Value
Street, S. (2006) · Philosophical Studies · doi:10.1007/s11098-005-1726-6 · Cited by 1,247 · see citing works
Evolutionary Psychology: A New Paradigm for Psychological Science
Buss, D. M. (1995) · Psychological Inquiry · doi:10.1207/s15327965pli0601_1 · Cited by 1,198 · see citing works
Brown, S. L., Nesse, R. M., Vinokur, A. D., & Smith, D. M. (2003) · Psychological Science · doi:10.1111/1467-9280.14461 · Cited by 1,142 · see citing works
Punishment in animal societies
Clutton-Brock, T. H., & Parker, G. A. (1995) · Nature · doi:10.1038/373209a0 · Cited by 1,043 · see citing works
A functional imaging study of cooperation in two-person reciprocal exchange
McCabe, K., Houser, D., Ryan, L., Smith, V., & Trouard, T. (2001) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.211415698 · Cited by 984 · see citing works
Fischer, P., Krueger, J. I., Greitemeyer, T., Vogrincic, C., Kastenmüller, A., Frey, D., Heene, M., Wicher, M., & Kainbacher, M. (2011) · Psychological Bulletin · doi:10.1037/a0023304 · Cited by 983 · see citing works
Lakin, J. L., Jefferis, V. E., Cheng, C. M., & Chartrand, T. L. (2003) · Journal of Nonverbal Behavior · doi:10.1023/a:1025389814290 · Cited by 960 · see citing works
Cooperation between non-kin in animal societies
Clutton-Brock, T. (2009) · Nature · doi:10.1038/nature08366 · Cited by 951 · see citing works
Van Lange, P. A. M., De Bruin, E. M. N., Otten, W., & Joireman, J. A. (1997) · Journal of Personality and Social Psychology · doi:10.1037/0022-3514.73.4.733 · Cited by 1,209 · see citing works
The evolution of personality variation in humans and other animals.
Nettle, D. (2006) · American Psychologist · doi:10.1037/0003-066x.61.6.622 · Cited by 885 · see citing works
Evolutionary explanations of emotions
Nesse, R. M. (1990) · Human Nature · doi:10.1007/bf02733986 · Cited by 884 · see citing works
The Ontogenesis of Social Dominance: A Strategy-Based Evolutionary Perspective
Hawley, P. H. (1999) · Developmental Review · doi:10.1006/drev.1998.0470 · Cited by 877 · see citing works
Effort for Payment: A Tale of Two Markets
Heyman, J., & Ariely, D. (2004) · Psychological Science · doi:10.1111/j.0956-7976.2004.00757.x · Cited by 827 · see citing works
The Neuroscience of Social Decision-Making
Rilling, J. K., & Sanfey, A. G. (2011) · Annual Review of Psychology · doi:10.1146/annurev.psych.121208.131647 · Cited by 775 · see citing works
Individual recognition: it is good to be different
Tibbetts, E. A., & Dale, J. (2007) · Trends in Ecology & Evolution · doi:10.1016/j.tree.2007.09.001 · Cited by 779 · see citing works
Cooperative behavior cascades in human social networks
Fowler, J. H., & Christakis, N. A. (2010) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.0913149107 · Cited by 767 · see citing works
Emotion, Social Function, and Psychopathology
Keltner, D., & Kring, A. M. (1998) · Review of General Psychology · doi:10.1037/1089-2680.2.3.320 · Cited by 773 · see citing works
Evolution of the Social Contract
Skyrms, B. (2014) · doi:10.1017/cbo9781139924825 · Cited by 743 · see citing works
Positive Interactions Promote Public Cooperation
Rand, D. G., Dreber, A., Ellingsen, T., Fudenberg, D., & Nowak, M. A. (2009) · Science · doi:10.1126/science.1177418 · Cited by 715 · see citing works
Happiness in Everyday Life: The Uses of Experience Sampling
Csikszentmihalyi, M., & Hunter, J. (2003) · Journal of Happiness Studies · doi:10.1023/a:1024409732742 · Cited by 717 · see citing works
Emmons, R. A., & McCullough, M. E. (2003) · Journal of Personality and Social Psychology · doi:10.1037//0022-3514.84.2.377 · Cited by 716 · see citing works
Dreber, A., Rand, D. G., Fudenberg, D., & Nowak, M. A. (2008) · Nature · doi:10.1038/nature06723 · Cited by 718 · see citing works
Stellar, J. E., Gordon, A. M., Piff, P. K., Cordaro, D., Anderson, C. L., Bai, Y., Maruskin, L. A., & Keltner, D. (2017) · Emotion Review · doi:10.1177/1754073916684557 · Cited by 696 · see citing works
Reputation-based partner choice promotes cooperation in social networks
Fu, F., Hauert, C., Nowak, M. A., & Wang, L. (2008) · Physical Review E · doi:10.1103/physreve.78.026117 · Cited by 682 · see citing works
Evolution of cooperation through indirect reciprocity
Leimar, O., & Hammerstein, P. (2001) · Proceedings of the Royal Society of London. Series B: Biological Sciences · doi:10.1098/rspb.2000.1573 · Cited by 673 · see citing works
Synchrony and the social tuning of compassion.
Valdesolo, P., & DeSteno, D. (2011) · Emotion · doi:10.1037/a0021302 · Cited by 654 · see citing works
Cognitive empathy and emotional empathy in human behavior and evolution
Smith, A. (2006) · The Psychological Record · doi:10.1007/bf03395534 · Cited by 654 · see citing works
Haidt, J., & Joseph, C. (2008) · The Innate Mind, Volume 3 · doi:10.1093/acprof:oso/9780195332834.003.0019 · Cited by 650 · see citing works
More effective choice in the prisoner's dilemma
Axelrod, R. (1980) · Journal of Conflict Resolution · doi:10.1177/002200278002400301 · Cited by 616 · see citing works
To give and to give not: the behavioral ecology of human food transfers
Gurven, M. (2004) · Behavioral and Brain Sciences · doi:10.1017/s0140525x04000123 · Cited by 582 · see citing works
Strohminger, N., & Nichols, S. (2014) · Cognition · doi:10.1016/j.cognition.2013.12.005 · Cited by 596 · see citing works
The neural bases of cooperation and competition: an fMRI investigation
Decety, J., Jackson, P. L., Sommerville, J. A., Chaminade, T., & Meltzoff, A. N. (2004) · NeuroImage · doi:10.1016/j.neuroimage.2004.05.025 · Cited by 578 · see citing works
Stakeholders, reciprocity, and firm performance
Bosse, D. A., Phillips, R. A., & Harrison, J. S. (2009) · Strategic Management Journal · doi:10.1002/smj.743 · Cited by 558 · see citing works
The bright side of being blue: depression as an adaptation for analyzing complex problems.
Andrews, P. W., & Thomson, J. A. (2009) · Psychological Review · doi:10.1037/a0016242 · Cited by 549 · see citing works
Theory of mind—evolution, ontogeny, brain mechanisms and psychopathology
Brüne, M., & Brüne-Cohrs, U. (2006) · Neuroscience & Biobehavioral Reviews · doi:10.1016/j.neubiorev.2005.08.001 · Cited by 540 · see citing works
Mere Belonging: The Power of Social Connections
Walton, G. M., Cohen, G. L., Cwir, D., & Spencer, S. J. (2012) · Journal of Personality and Social Psychology · doi:10.1037/a0025731 · Cited by 543 · see citing works
Curry, O. S., Rowland, L. A., Van Lissa, C. J., Zlotowitz, S., McAlaney, J., & Whitehouse, H. (2018) · Journal of Experimental Social Psychology · doi:10.1016/j.jesp.2018.02.014 · Cited by 528 · see citing works
The rhythm of joint action: synchrony promotes cooperative ability.
Valdesolo, P., Ouyang, J., & DeSteno, D. (2010) · Journal of Experimental Social Psychology · doi:10.1016/j.jesp.2010.03.004 · Cited by 521 · see citing works
Lodi-Smith, J., & Roberts, B. W. (2007) · Personality and Social Psychology Review · doi:10.1177/1088868306294590 · Cited by 513 · see citing works
Partner choice creates competitive altruism in humans
Barclay, P., & Willer, R. (2007) · Proceedings of the Royal Society B: Biological Sciences · doi:10.1098/rspb.2006.0209 · Cited by 485 · see citing works
The Ties That Bind Us: Ritual, Fusion, and Identification
Whitehouse, H., & Lanman, J. A. (2014) · Current Anthropology · doi:10.1086/678698 · Cited by 509 · see citing works
Placebo and the New Physiology of the Doctor-Patient Relationship
Benedetti, F. (2013) · Physiological Reviews · doi:10.1152/physrev.00043.2012 · Cited by 492 · see citing works
Society-in-the-loop: programming the algorithmic social contract
Rahwan, I. (2018) · Ethics and Information Technology · doi:10.1007/s10676-017-9430-8 · Cited by 553 · see citing works
McKay, R. T., & Dennett, D. C. (2009) · Behavioral and Brain Sciences · doi:10.1017/s0140525x09990975 · Cited by 474 · see citing works
Short-term compassion training increases prosocial behavior in a newly developed prosocial game
Leiberg, S., Klimecki, O., & Singer, T. (2011) · PLoS ONE · doi:10.1371/journal.pone.0017798 · Cited by 442 · see citing works
Major evolutionary transitions in individuality
West, S. A., Fisher, R. M., Gardner, A., & Kiers, E. T. (2015) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.1421402112 · Cited by 431 · see citing works
Martela, F., & Ryan, R. M. (2016) · Journal of Personality · doi:10.1111/jopy.12215 · Cited by 422 · see citing works
The contribution of source–filter theory to mammal vocal communication research
Taylor, A. M., & Reby, D. (2010) · Journal of Zoology · doi:10.1111/j.1469-7998.2009.00661.x · Cited by 407 · see citing works
Neural correlates of social cooperation and non-cooperation as a function of psychopathy
Rilling, J. K., Glenn, A. L., Jairam, M. R., Pagnoni, G., Goldsmith, D. R., Elfenbein, H. A., & Lilienfeld, S. O. (2007) · Biological Psychiatry · doi:10.1016/j.biopsych.2006.07.021 · Cited by 408 · see citing works
Précis of <i>The brain and emotion</i>
Rolls, E. T. (2000) · Behavioral and Brain Sciences · doi:10.1017/s0140525x00002429 · Cited by 397 · see citing works
A tale of two defectors: the importance of standing for evolution of indirect reciprocity
Panchanathan, K., & Boyd, R. (2003) · Journal of Theoretical Biology · doi:10.1016/s0022-5193(03)00154-1 · Cited by 388 · see citing works
Monoamine oxidase A gene (MAOA) predicts behavioral aggression following provocation
McDermott, R., Tingley, D., Cowden, J., Frazzetto, G., & Johnson, D. D. P. (2009) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.0808376106 · Cited by 384 · see citing works
Neural basis of extraordinary empathy and altruistic motivation
Mathur, V. A., Harada, T., Lipke, T., & Chiao, J. Y. (2010) · NeuroImage · doi:10.1016/j.neuroimage.2010.03.025 · Cited by 377 · see citing works
The origins of altruism in offspring care.
Preston, S. D. (2013) · Psychological Bulletin · doi:10.1037/a0031755 · Cited by 368 · see citing works
Structured Demes and the Evolution of Group-Advantageous Traits
Wilson, D. S. (1977) · The American Naturalist · doi:10.1086/283146 · Cited by 363 · see citing works
Rilling, J. K., DeMarco, A. C., Hackett, P. D., Chen, X., Gautam, P., Stair, S., Haroon, E., Thompson, R., Ditzen, B., Patel, R., et al. (2014) · Psychoneuroendocrinology · doi:10.1016/j.psyneuen.2013.09.022 · Cited by 343 · see citing works
“The iterated Prisoner’s Dilemma game is a model for relationships based on reciprocal altruism (Trivers, 1971).”
BackgroundMethodInfluentialDynamical evolutionary psychology: Individual decision rules and emergent social norms.
Kenrick, D. T., Li, N. P., & Butner, J. (2003) · Psychological Review · doi:10.1037/0033-295x.110.1.3 · Cited by 358 · see citing works
McKay, R., & Whitehouse, H. (2015) · Psychological Bulletin · doi:10.1037/a0038455 · Cited by 353 · see citing works
Social status and group norms: Indirect reciprocity in a repeated helping experiment
Seinen, I., & Schram, A. (2006) · European Economic Review · doi:10.1016/j.euroecorev.2004.10.005 · Cited by 350 · see citing works
The intelligence of the moral intuitions: A comment on Haidt (2001).
Pizarro, D. A., & Bloom, P. (2003) · Psychological Review · doi:10.1037/0033-295x.110.1.193 · Cited by 345 · see citing works
Emotion, decision making, and the amygdala.
Seymour, B., & Dolan, R. (2008) · Neuron · doi:10.1016/j.neuron.2008.05.020 · Cited by 324 · see citing works
- Authors
- Trivers, R. L.
- Corresponding author
- Trivers, Robert L.
- ORCID
- Trivers, Robert L.
- Venue
- The Quarterly Review of Biology
- Publisher
- University of Chicago Press
- Published
- 1971-03
- Volume
- 46
- Issue
- 1
- Pages
- 35-57
- ISSN
- 0033-5770 (ISSN-L)
- 1539-7718
- OpenAlex
- W2167030552
- Cited by
- 11,010
- References
- 2
- Citations by year
- 2026: 266 · 2025: 301 · 2024: 423 · 2023: 331 · 2022: 418 · 2021: 511 · 2020: 470 · 2019: 458 · 2018: 445 · 2017: 376 · 2016: 442 · 2015: 453 · 2014: 431 · 2013: 426 · 2012: 433
- FWCI
- 50.24
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- The Quarterly Review of Biology (publishedVersion)
- Topics
- Social Sciences › Sociology and Political Science › Evolutionary Game Theory and Cooperation
- Social Sciences › Psychology › Experimental and Cognitive Psychology › Evolutionary Psychology and Human Behavior
- Life Sciences › Agricultural and Biological Sciences › Ecology, Evolution, Behavior and Systematics › Animal Behavior and Reproduction
- Keywords
- reciprocal altruism, evolution of cooperation, cheaters, cleaning symbiosis, moral emotions, trust, guilt, dishonesty, hypocrisy
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