Evolving Specialisation, Altruism, and Group-Level Optimisation Using Tags

Abstract

We present a model that demonstrates the evolution of groups composed of cooperative individuals performing specialised functions. Specialisation and cooperation results from an evolutionary process in which selection and reproduction is based on individual fitness. Specialists come to help (through the donation of resources) their non-kin group members, optimising their behaviour as a team and producing a fitter group. The mechanism that promotes this benevolent, cooperative group behaviour is based on the concept of a “tag”. Tags¹ are observable markings, cues or displays. Individuals can observe the tags of others and take alternative actions based on those observations (e.g. to altruistically² help or not). We show that even random (or dumb) searching for appropriate partners produces significant levels of specialisation and cooperation. Additionally we demonstrate that non-random (or smart) searching dramatically increases the effect.

The concept of “tags” in the context of structuring social interactions among agents was first outlined by Holland [6] and applied to repeated interactions by Riolo [7].

By altruism, we mean that agents sacrifice fitness for others even though such donations may not be returned (i.e. without reciprocity).

In these previous models when identical agents are paired they must act altruistically.