This paper addresses the emergence of a common phonetic code in a society of communicating speech agents using evolutionary techniques. Predictions for the large vowel systems of the world's languages using the Maximum Use of Available distinctive Features (MUAF) principle are discussed. Simulations of the use of supplementary phonetic features in large vowel systems are presented. These experimental results show how simple local rules of interaction between speaking agents are sufficient to explain some of the universal characteristics of the phonological structure of the world's languages.