Divergent cumulative cultural evolution occurs when the cultural evolutionary trajectory diverges from the biological evolutionary trajectory. We consider the conditions under which divergent cumulative cultural evolution can occur. We hypothesize that two conditions are necessary. First that genetic and cultural information are stored separately in the agent. Second cultural information must be transferred horizontally between agents of different generations. We implement a model with these properties and show evidence of divergent cultural evolution under both cooperative and competitive selection pressures.

We present a model for evolving agents using both genetic and cultural inheritance mechanisms. Within each agent our model maintains two distinct information stores we call the genome and the memome. Processes of adaptation are modeled as evolutionary processes at each level of adaptation (phylogenetic, ontogenetic, sociogenetic). We review relevant competing models and we show how our model improves on previous attempts to model genetic and cultural evolutionary processes. In particular we argue our model can achieve divergent gene-culture co-evolution.

Sexual reproductive behavior has a necessary social coordination component as willing and capable partners must both be in the right place at the right time. It has recently been demonstrated that many social organizations that support sexual reproduction can evolve in the absence of social coordination between agents (e.g. herding, assortative mating, and natal philopatry). In this paper we explore these results by including social transfer mechanisms to our agents and contrasting their reproductive behavior with a control group without social transfer mechanisms. We conclude that similar behaviors emerge in our social learning agents as those that emerged in the non-social learning agents. Social learners were more inclined towards natal philopatry. Social learners also evolved a culture of eusociality including reproductive division of labor.