An emergent behaviour is one that arises in a system as whole, but is not immedaitely obvious from the constituent parts. Often an AI system has many agents or rules, each of which is simple, but where the overall system behaves in ways that are not at all obvious. Emergent behaviours often occurs in swarm computing and can be used in CGI to model flocks of birds or herds of animals.
Defined on pages 383, 383
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