Biological altruism in hostile environments

Abstract

Abstract: An agent-based computer model was used to investigate the effects of periodic local extinctions on the stabilization of cooperation in evolutionary prisoner’s dilemma. The model allows increasing population densities which tend to undermine standard non-discriminating “solutions. ” The results show that for intermediate extinction rates, there is a window of opportunity for cooperation to flourish. Random extinction patterns both create environments where pure communities of cooperators survive through dissemination better than mixed and defector communities and insulate such communities from invasion. This suggests that geographical “edges of survivability ” may provide the conditions under which cooperation can emerge and discriminating mechanisms evolve. The evolution of economic altruism is one of the most vigorous areas of study at the intersection of biology, economics, and philosophy. The basic problem is easily understood. Biological organisms, be they people or paramecia, have ample opportunity to confer benefits on others at relatively low cost to themselves. If conferring such benefits becomes common, the overall productivity of the population in which it occurs is increased. Presumably, there is no advantage to refusing such benefits, but it is also the case that there is considerable advantage to pursuing a strategy according to which such benefits are accepted, but not conferred. In