Evolutionary Game Theory: Natural Selection Is a Strategy

John Maynard Smith's Framework

In 1973, biologist John Maynard Smith applied game theory to evolution, replacing "rational agents choosing strategies" with "organisms whose inherited behaviors act as strategies, selected by fitness payoffs." An Evolutionarily Stable Strategy (ESS) is a behavioral strategy that, if adopted by a population, cannot be invaded by a mutant with a different strategy. The concept unified biology and mathematics in a way that neither field had anticipated.

Hawk-Dove: The Origin of Ritualized Conflict

The Hawk-Dove game models competition for resources. Hawks always fight; Doves always retreat. A population of all Hawks destroys itself through constant injury. A population of all Doves is invaded by Hawks. Evolution stabilizes at a mixed equilibrium — a ratio of aggressive and submissive behaviors that maximizes average fitness. This explains why most animal conflicts involve ritualized display rather than lethal combat: restraint evolved because it is the ESS, not because animals are moral. These dynamics underpin the Game Theory & Strategy of all social organisms.

The Evolution of Cooperation

The deepest puzzle evolutionary game theory addresses is why cooperation exists at all among unrelated individuals. Kin selection explains altruism toward relatives. But among strangers? Reciprocal altruism, reputation effects, and group selection each provide partial answers. Robert Axelrod's Tit-for-Tat results suggest cooperation emerges from repeated interaction — the shadow of the future disciplines present behavior.

Implications for Human Nature

Evolutionary game theory suggests that human moral intuitions — fairness, reciprocity, punishment of defectors — are not cultural impositions but mathematical attractors. We feel outrage at unfairness not because we were taught to but because populations with that response outcompeted populations without it. Morality, in this framework, is evolution's solution to the coordination problems described by the Prisoner's Dilemma.