  This paper aims to shed light on the evolutionary dynamics of diverse and
social populations by introducing the rich expressiveness of generative models
into the trait expression of social agent-based evolutionary models.
Specifically, we focus on the evolution of personality traits in the context of
a game-theoretic relationship as a situation in which inter-individual
interests exert strong selection pressures. We construct an agent model in
which linguistic descriptions of personality traits related to cooperative
behavior are used as genes. The deterministic strategies extracted from Large
Language Model (LLM) that make behavioral decisions based on these personality
traits are used as behavioral traits. The population is evolved according to
selection based on average payoff and mutation of genes by asking LLM to
slightly modify the parent gene toward cooperative or selfish. Through
preliminary experiments and analyses, we clarify that such a model can indeed
exhibit the evolution of cooperative behavior based on the diverse and
higher-order representation of personality traits. We also observed the
repeated intrusion of cooperative and selfish personality traits through
changes in the expression of personality traits, and found that the emerging
words in the evolved gene well reflected the behavioral tendency of its
personality in terms of their semantics.
