Theory of Cooperation

Cooperation is defined as any adaptation that has evolved, at least in part, to increase the reproductive success of the actor's social partners. Inclusive fitness theory reveals that cooperation can be favoured by natural selection owing to either direct fitness benefits (mutually beneficial cooperation) or indirect fitness benefits (altruistic cooperation). Direct fitness benefits can arise as a simple byproduct of cooperation, or else owing to the existence of enforcement mechanisms, which may be fixed or conditioned according to the individual's cooperative behaviour. Indirect fitness benefits can arise when cooperation occurs between genetically similar individuals, as a consequence of limited dispersal, kin discrimination or greenbeard mechanisms. These theoretical mechanisms are illustrated with empirical examples, from laboratory experiments to field studies.

Key concepts:

  • The function of Darwinian adaptation is to maximize the organism's inclusive fitness.
  • Inclusive fitness describes how well an organism transmits copies of its genes to future generations.
  • Direct fitness is the part of inclusive fitness that comes from the organism's own reproductive success.
  • Indirect fitness is the part of inclusive fitness that comes from the reproductive success of the organism's genetic relatives.
  • Cooperation is any adaptation whose function is, at least in part, to increase the reproductive success of a social partner.
  • Cooperation is mutually beneficial if the actor also benefits and altruistic if the actor suffers a net loss of reproductive success.
  • Mutually beneficial cooperation is favoured by direct fitness benefits.
  • Direct fitness benefits can arise as a byproduct or owing to enforcement mechanisms.
  • Altruistic cooperation is favoured by indirect fitness benefits.
  • Indirect fitness benefits can arise as a consequence of limited dispersal, kin discrimination or greenbeard mechanisms.

Keywords: altruism; Hamilton's rule; inclusive fitness; kin selection; social evolution

Figure 1. Inclusive fitness is the sum of direct fitness and indirect fitness. Social behaviours affect the reproductive success of individuals beyond the actor. The impact on the actor's own reproductive success is the direct fitness effect. The impact on the reproductive success of social partners, weighted by the relatedness of the actor to the recipient, is the indirect fitness effect. In particular, inclusive fitness does not include all the reproductive success of relatives, only that which is due to the behaviour of the actor (yellow hands). Also, inclusive fitness does not include any of the reproductive success of the actor that is due to the actions of its social partners (blue hands). Reproduced from West et al. (2007a). Reproduced with permission from Elsevier.
Figure 2. Mechanisms generating direct fitness benefits for cooperation. (a) Byproduct benefit. Helping a social partner may lead to increases in the overall fitness of all individuals in a social group; for example, in situations where larger social groups offer better protection against predators, the actor could benefit from helping its neighbours to reproduce (group augmentation). (b) Conditional enforcement. Helping may lead to a change in the behaviour of the recipient or a third party, in a way that leads to an overall direct fitness benefit for the actor; for example, direct reciprocity ensures that cooperators receive more cooperation than cheats, giving a direct benefit to cooperation even if each act involves an immediate cost. (c) Unconditional enforcement. Helping may be the only option available to an individual, if the possibility for it to behave selfishly is ruled-out by a successful system of policing.
Figure 3. Cooperation and punishment in humans. Humans show higher levels of cooperation in economic games, when there are opportunities to punish individuals who do not cooperate (Fehr and Gächter, 2002). Thanks to E. Fehr for data and O. Henderson for illustration. Reproduced from West et al. (2007a). Reproduced with permission from Elsevier.
Figure 4. Mechanisms generating indirect fitness benefits for cooperation. (a) Limited dispersal. If individuals do not move far during their lifetime, then they will tend to be surrounded by kin (shaded) and hence even indiscriminate altruism could be directed primarily towards kin rather than nonkin. (b) Kin discrimination. For example, if the actor can remember those individuals it shared a nest with when young and discriminate these kin (shaded) from nonkin (unshaded) after leaving the nest, then cooperation can be directed primarily towards genetic relatives. (c) Greenbeard. If the gene controlling altruism is also associated with a phenotypic marker, such as a green beard, then green-bearded individuals can identify which of their neighbours carries a copy of the gene. Altruism directed at genetic relatives can be favoured by natural selection, even if these are not genealogical relatives (kin).
Figure 5. Kin discrimination in long-tailed tits. Ninety-four percent of helpers prefer to help at nests containing related chicks when they have the choice of where to invest their efforts (Russell and Hatchwell, 2001). Thanks to O. Henderson for illustration. Reproduced from West et al. (2007a). Reproduced with permission from Elsevier.
close
 References
    Avilés L and Tufiño P (1998) Colony size and individual fitness in the social spider Anelosimus eximius. American Naturalist 152: 403–418.
    Axelrod R and Hamilton WD (1981) The evolution of cooperation. Science 211: 1390–1396.
    Bernasconi G and Strassmann JE (1999) Cooperation among unrelated individuals: the ant foundress case. Trends in Ecology & Evolution 14: 477–482.
    Boomsma JJ, Nielsen J, Sundstrom L et al. (2003) Informational constraints on optimal sex allocation in ants. Proceedings of the National Academy of Sciences of the USA 100: 8799–8804.
    book Burt A and Trivers R (2006) Genes in Conflict. Harvard: Belknap Press.
    Clutton-Brock TH and Parker GA (1995) Punishment in animal societies. Nature 373: 209–216.
    Clutton-Brock TH (2002) Breeding together: kin selection, reciprocity and mutualism in cooperative animal societies. Science 296: 69–72.
    Clutton-Brock TH, Brotherton PNM, Oriain MJ et al. (2000) Individual contributions to babysitting in a cooperative mongoose, Suricata suricatta. Proceedings of the Royal Society of London Series B 267: 301–305.
    Clutton-Brock TH, Russell AF, Sharpe LL et al. (2002) Evolution and development of sex differences in cooperative behavior in Meerkats. Science 297: 253–256.
    Dani FR, Foster KR, Zacchi F et al. (2004) Can cuticular lipids provide sufficient information for within-colony nepotism in wasps? Proceedings of the Royal Society of London Series B 271: 745–753.
    book Darwin CR (1859) The Origin of Species. London: John Murray.
    book Dawkins R (1976) The Selfish Gene. Oxford: Oxford University Press.
    Emlen ST and Wrege PH (1992) Parent-offspring conflict and the recruitment of helpers among bee-eaters. Nature 356: 331–333.
    Fehr E and Gächter S (2002) Altruistic punishment in humans. Nature 415: 137–140.
    book Fisher RA (1930) The Genetical Theory of Natural Selection. Oxford: Clarendon Press.
    book Frank SA (1998) Foundations of Social Evolution Theory. Princeton, NJ: Princeton University Press.
    Frank SA (2003) Repression of competition and the evolution of cooperation. Evolution 57: 693–705.
    Gardner A and West SA (2006) Demography, altruism, and the benefits of budding. Journal of Evolutionary Biology 19: 1707–1716.
    Grafen A (2006) Optimisation of inclusive fitness. Journal of Theoretical Biology 238: 541–563.
    Griffin AS and West SA (2003) Kin discrimination and the benefit of helping in cooperatively breeding vertebrates. Science 302: 634–636.
    Griffin AS, West SA and Buckling A (2004) Cooperation and competition in pathogenic bacteria. Nature 430: 1024–1027.
    Hamilton WD (1963) The evolution of altruistic behaviour. American Naturalist 97: 354–356.
    Hamilton WD (1964) The genetical evolution of social behaviour, I & II. Journal of Theoretical Biology 7: 1–52.
    Hamilton WD (1970) Selfish and spiteful behaviour in an evolutionary model. Nature 228: 1218–1220.
    book Hamilton WD (1971) "Selection of selfish and altruistic behaviour in some extreme models". In: Eisenberg JF and Dillon WS (eds) Man and Beast: Comparative Social Behavior, pp. 57–91. Washington, DC: Smithsonian Press.
    book Hamilton WD (1996) Narrow Roads of Geneland. Vol 1: Evolution of Social Behaviour. Oxford: Freeman.
    book Hammerstein P (2003) Genetic and Cultural Evolution of Cooperation. Cambridge, MA: MIT Press.
    Hardin G (1968) The tragedy of the commons. Science 162: 1243–1248.
    Kokko H, Johnstone RA and Clutton-Brock TH (2001) The evolution of cooperative breeding through group augmentation. Proceedings of the Royal Society of London Series B 268: 187–196.
    Kümmerli R, Gardner A, West SA and Griffin AS (2009) Limited dispersal, budding dispersal and cooperation: an experimental study. Evolution 63: 939–949.
    Lehmann L and Keller L (2006) The evolution of cooperation and altruism. A general framework and classification of models. Journal of Evolutionary Biology 19: 1365–1378.
    book Leigh EG (1971) Adaptation and Diversity. San Francisco, CA: Freeman, Cooper & Co.
    book Maynard Smith J and Szathmáry E (1995) The Major Transitions in Evolution. Oxford: WH Freeman.
    Michod RE and Roze D (2001) Cooperation and conflict in the evolution of multicellularity. Heredity 86: 1–7.
    Price GR (1970) Selection and covariance. Nature 227: 520–521.
    Queller DC (1992) Does population viscosity promote kin selection? Trends in Ecology & Evolution 7: 322–324.
    Queller DC, Ponte E, Bozzaro S and Strassmann JE (2003) Single-gene greenbeard effects in the social amoeba Dictostelium Discoideum. Science 299: 105–106.
    Queller DC, Zacchi F, Cervo R et al. (2000) Unrelated helpers in a social insect. Nature 405: 784–787.
    Ratnieks FLW (1988) Reproductive harmony via mutual policing by workers in eusocial Hymenoptera. American Naturalist 132: 217–236.
    Ratnieks FLW and Visscher PK (1989) Worker policing in the honeybee. Nature 342: 796–797.
    Russell AF and Hatchwell BJ (2001) Experimental evidence for kin-biased helping in a cooperatively breeding vertebrate. Proceedings of the Royal Society of London Series B 268: 2169–2174.
    Sachs JL, Mueller UG, Wilcox TP and Bull JJ (2004) The evolution of cooperation. Quarterly Review of Biology 79: 135–160.
    Stevens J and Hauser MD (2004) Why be nice? Psychological constraints on the evolution of cooperation. Trends in Cognitive Sciences 8: 60–65.
    Taylor PD (1992) Inclusive fitness in a heterogeneous environment. Proceedings of the Royal Society of London Series B 249: 299–302.
    Trivers RL (1971) The evolution of reciprocal altruism. Quarterly Review of Biology 46: 35–57.
    Wenseleers T and Ratnieks FLW (2006) Enforced altruism in insect societies. Nature 444: 50.
    West SA, Griffin AS and Gardner A (2007a) Evolutionary explanations for cooperation. Current Biology 17: R661–R672.
    West SA, Griffin AS and Gardner A (2007b) Social semantics: altruism, cooperation, mutualism, strong reciprocity and group selection. Journal of Evolutionary Biology 20: 415–432.
    West SA, Pen I and Griffin AS (2002) Cooperation and competition between relatives. Science 296: 72–75.
    Wilkinson GS (1984) Reciprocal food sharing in the vampire bat. Nature 308: 181–184.
    Young AJ, Carlson AA, Monfort SL et al. (2006) Stress and the suppression of subordinate reproduction in cooperatively breeding meerkats. Proceedings of the National Academy of Sciences of the USA 103: 12005–12010.
Contact Editor close
Submit a note to the editor about this article by filling in the form below.

* Required Field

How to Cite close
Gardner, Andy, Griffin, Ashleigh S, and West, Stuart A(Dec 2009) Theory of Cooperation. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0021910]