concept

Escalation

The kind of arms race in which both sides genuinely improve in absolute capability over time - sharper teeth answered by thicker hide, better sonar answered by better ears - rather than merely trading the advantage back and forth. It is worth distinguishing from cycling around an equilibrium, where the two sides swap roles generation by generation and neither actually gets better. Escalation is asymmetric: the life-dinner principle notes that a failed prey dies while a failed predator only goes hungry, so selection presses harder on escape than on capture, and prey tend to out-invest.