Intuitive verbal arguments are sufficient to describe evolutionary outcomes between behaviorally interacting organisms. Sociobiologists focus on the behavioral strategies employed by socially interacting individuals, but before the deployment of game theory there was no cohesive framework for interpreting the long-term (evolutionary) outcomes of alternative behavioral tactics. Game theory can be defined as the study of strategic decision-making. Traditionally used in economics, political science, and psychology, it entails development of mathematical models describing which among two or more competing behavioral tactics yields the greatest payoff (e.g., money) to its practitioners. In human social behavior, applications include bargaining encounters, justice, ultimatum games, commitment choices, decisions about mutual aid versus defection, hawk–dove interactions, ownership issues, and truth versus deception in communications and signaling.
game theory; behavioral tactics
Intuitive verbal arguments are sufficient to describe evolutionary outcomes between behaviorally interacting organisms. Sociobiologists (see Chapter 32) focus on the behavioral strategies employed by socially interacting individuals, but before the deployment of game theory there was no cohesive framework for interpreting the long-term (evolutionary) outcomes of alternative behavioral tactics. Game theory can be defined as the study of strategic decision-making. Traditionally used in economics, political science, and psychology, it entails development of mathematical models describing which among two or more competing behavioral tactics yields the greatest payoff (e.g., money) to its practitioners. In human social behavior, applications include bargaining encounters, justice, ultimatum games, commitment choices, decisions about mutual aid versus defection, hawk–dove interactions, ownership issues, and truth versus deception in communications and signaling.
The application of game theory in an evolutionary context was introduced to biology in the 1970s (although some earlier treatments also exist), and was popularized in a landmark book by John Maynard Smith in 1982 (an achievement for which he later won a Crafoord Prize). This mathematical construct enabled biologists to quantitatively analyse and thereby evaluate competing behavioral tactics with regard to their ultimate payoff, which in the context of evolutionary biology is measured in terms of relative genetic fitness.
Game theory continues to find many applications in an animal’s “decision-making” in nature. For example, should a family produce mostly sons, mostly daughters, or some mixed tactic (see Chapter 18)? The usual goal in game theory is to illuminate behavioral tactic(s) that benefit personal fitness, and then to discover whether and under what circumstances particular tactics or combinations of tactics are evolutionarily stable (immune to invasion by alternative tactics) in a population. Each non-invasible outcome is an evolutionary stable strategy or ESS (i.e., the situation toward which a population tends to evolve if the assumptions underlying the model are correct).
1. Maynard Smith J. Evolution and the Theory of Games Cambridge, UK: Cambridge University Press; 1982.
2. Skyrms B. Evolution of the Social Contract Cambridge, UK: Cambridge University Press; 1996.
3. Maynard Smith J. Evolutionary Genetics 2nd edition Oxford, UK: Oxford University Press; 1998.
4. Osborne MJ. An Introduction to Game Theory New York, NY: Oxford University Press; 2004.