Strategy as an Evolved Trait
Evolutionary game theory analyzes social interactions in which the payoff of one individual's strategy depends on which strategies others in the population adopt. The Hawk-Dove game models conflict resolution over a shared resource: "Hawks" always escalate and fight, risking injury, while "Doves" display but retreat rather than fight. Neither pure strategy is stable on its own — an all-Dove population is easily invaded by a Hawk, and an all-Hawk population pays such heavy injury costs that Doves can do better — so the population typically settles at a mixed Evolutionarily Stable Strategy (ESS): a strategy that, once common, cannot be beaten by any rare alternative. In some species, a conditional strategy called Bourgeois — fight if you are the resource's owner, retreat if you are the intruder — emerges as the ESS instead.
The Prisoner's Dilemma is the classic model for cooperation between non-relatives. Although mutual cooperation yields the best collective payoff, each individual is tempted to defect (exploit a cooperating partner) for a higher personal payoff — and if both defect, both end up worse off than if both had cooperated. Robert Axelrod's computer tournaments, pitting many strategies against each other in repeated Prisoner's Dilemma games, found that a remarkably simple strategy — Tit-for-Tat (cooperate first, then simply mirror the partner's previous move) — outperformed far more complex rivals, by being nice, retaliatory, forgiving, and easy to read.
Common pitfall: assuming the "winning" strategy in a repeated Prisoner's Dilemma must be a cunning, deceptive one. Axelrod's tournaments found the opposite: transparent, reciprocal strategies like Tit-for-Tat that start cooperatively tend to outperform strategies built around exploiting others.
A Hawk-versus-Dove contest: two silhouettes face off over a resource icon; if both are Hawks, a clash animation plays and one retreats injured (accent red flash).