Language Evolution and Computation Bibliography

We examined the role of fitness, commonly assumed without proof to be conferred by the mastery of language, in shaping the dynamics of language evolution. To that end, we introduced island migration (a concept borrowed from population genetics) into the shared lexicon model of communication (Nowak et al., 1999). The effect of fitness linear in language coherence was compared to a control condition of neutral drift. We found that in the neutral condition (no coherence-dependent fitness) even a small migration rate - less than 1% - suffices for one language to become dominant, albeit after a long time. In comparison, when fitness-based selection is introduced, the subpopulations stabilize quite rapidly to form several distinct languages. Our findings support the notion that language confers increased fitness. The possibility that a shared language evolved as a result of neutral drift appears less likely, unless migration rates over evolutionary times were extremely small.

Human colour perception is continuous, but humans categorise the colour continuum and often label the resulting colour categories. The debate on whether colour categorisation is an individual process, or whether it is embedded in genetic constraints has not been settled yet. Further- more, as colour categories have colour names, it is claimed that language could have an influence on the categorisation. This paper reports on agent-based simulations that test the validity of dirent theories, and uncovers the weak and strong points of each. We conclude, from experi- ments using AI techniques, that colour categorisation is most likely to be cultural process.