Language Evolution and Computation Bibliography

A complete understanding of communication, language, intention- ality and related mental phenomena will require a theory integrating mechanistic explanations with ethological phenomena. For the foresee- able future, the complexities of natural life in its natural environment will preclude such an understanding. An approach more conducive to carefully controlled experiments and to the discovery of deep laws of great generality is to study synthetic life forms in a synthetic world to which they have become coupled through evolution. This is the approach of synthetic ethology. Some simple synthetic ethology ex- periments are described in which we have observed the evolution of communication in a population of simple machines. We show that even in these simple worlds we find some of the richness and complexity found in natural communication.

A population of artificial organisms evolved simple communication protocols for mate finding. Female animals in our artificial environment had the ability to see males and to emit sounds. Male animals were blind, but could hear signals from females. Thus, the environment was designed to favor organisms that evolved to generate and interpret meaningful signals. Starting with random neural networks, the simulation resulted in a progression of generations that exhibit increasingly effective mate-finding strategies. In addition, a number of distinct subspecies, i.e., groups with different signaling protocols or 'dialects,' evolve and compete. These protocols become a behavioral barrier to mating that supports the formation of distinct subspecies. Experiments with physical barriers in the environment were also performed. A partially permeable barrier allows a separate subspecies to evolve and survive for indefinite periods of time, in spite of occasional migration and contact from members of other subspecies.

In this paper, we introduce a framework for simulating cultural process. The general idea is to simulate a world in which learning agents create external structures which mediate their behavior. This simulation demonstrates the simple (but very important) concept that such a system is capable, through generations of time, of producing agents endowed with cognitive powers that are not attainable in the lifetime of any individual agent. We argue that such an outcome is possible without effecting the genetic organization of individuals. However, we also argue that the cultural process is capable of guiding both learning and phylogenetic evolution, which leaves open the possiblity of genetic organization tracking cultural process.