Red Queen dynamics: predator-prey coevolution on fitness landscapes
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Gen: 0
Prey trait: 0.50
Pred trait: 0.50
Gap: 0.00
The Red Queen hypothesis (Van Valen, 1973) states that organisms must evolve continuously just to maintain fitness relative to their coevolving antagonists. In predator-prey arms races, prey evolve defenses (toxicity, speed, camouflage) while predators evolve counter-adaptations. Each advance by one party selects for advance in the other. With costs, high trait values impose fitness penalties, creating an optimum and preventing unbounded escalation. Without costs, traits escalate indefinitely. The fitness landscape shifts as each population evolves, creating perpetual "Red Queen" cycling that can drive speciation.