evolutionarily stable strategies

An evolutionarily stable strategy (ESS) is a behavioral approach that, once common in a population, cannot be easily replaced by an alternative strategy because it provides the best advantage for survival and reproduction. Imagine animals behaving in ways that maximize their success; if most behave in a certain way, any newcomer adopting a different tactic won't outperform the established behavior. Over time, these strategies persist because they are resistant to being outcompeted by mutants or alternatives, helping explain how certain behaviors become fixed in a species through natural selection.