Self-Organized Segregation within an Evolving Population
  An evolving population, in which individual members (`agents') adapt their behaviour according to past experience, is of central importance to many disciplines. Because of their limited knowledge and capabilities, agents are forced to make decisions based on inductive, rather than deductive, thinking. We show that a population of competing agents with similar capabilities and knowledge will tend to self-segregate into opposing groups characterized by extreme behavior. Cautious agents perform poorly and tend to become rare. 
Neil F. Johnson, Pak Ming Hui, Rob Jonson and Ting Shek Lo (Oxford   University and Chinese University of Hong Kong)