ABSTRACT
Aid to co-ethnics that reduces the giver’s individual fitness (ethnic altruism) risks being maladaptive, or ‘evolutionarily unstable’. Hamilton formulated a criterion for adaptive altruism, referred to as Hamilton’s Rule. This is based on his theory of inclusive fitness theory, which he developed to explain altruism. The theory states that altruism can be adaptive when it tends to preserve or increase the altruist’s genetic representation in the next generation. However, adaptive altruism must overcome the risks of free riders and maldistribution of resources. Despite these risks, Hamilton argued that altruism directed towards the tribe can, in principle, be adaptive. The large aggregate kinship contained by ethnic groups supports Hamilton’s view.
