%A Bruce Edmonds %T Gossip, Sexual Recombination and the El Farol Bar: modelling the emergence of heterogeneity %X Brian Arthur's `El Farol Bar' model is extended so that the agents also learn and communicate. The learning and communication is implemented using an evolutionary process acting upon a population of mental models inside each agent. The evolutionary process is based on a Genetic Programming algorithm. Each gene is composed of two tree-structures: one to control its action and one to determine its communication. A detailed case-study from the simulations show how the agents have differentiated so that by the end of the run they had taken on very different roles. Thus the introduction of a flexible learning process and an expressive internal representation has allowed the emergence of heterogeneity. %D 1998 %K learning, social, agents, genetic programming, heterogenaity, emergence, representation, expressiveness, naming, simulation, economics, multi-agent systems %L cogprints514