Evolutionary Model
The game theoretic approach is not completely satisfactory in so far as it implicitly assumes an under-socialised conception of human action. The possibility of cooperation is enhanced in groups whose members are tied together through the sharing of common ethos or social norms. A repeated game, however, falls in the category of evolutionary model, wherein the payoffs keep on changing from time to time.
There are two aspects of evolutionary model, namely the evolution of social norms and the evolution of participatory institutions. The latter is, however, dependent upon the former. Evolving social norms of behaviour - away from the pursuit of self-interest - is a long-drawn-out process. It depends upon the level of understanding about the outcomes of collective action, obligations required, responsibilities to be delegated, and restrictions on individual behaviour. However, they are more stable if and when evolved internally than when imposed externally.
In terms of the evolution of institutions, the role of a third group of agents called 'enforcers' or 'willing punishers' is envisaged, where the institution can be instrumental in stabilising equilibrium collective action solutions to the management of the commons. Whether these should be external agents such as the state or evolved within is a matter of practical experience in different situations. For instance, in several irrigation water use situations, invariably the majority decision regarding water sharing rules is more stable than that imposed by the governmental agencies.
The experience with community management in one situation can trigger similar institutions elsewhere. Therefore, the growth of participatory institutions itself can be evolutionary. One can trace out at least three broad thoughts through which institutions to manage CPRs have evolved. First, traditional societies in India have evolved systems to manage them through a process of conflicts, learning, and mechanisms to resolve them. The tribal’s of India residing in forest areas have always dealt with this issue in this evolutionary manner. Second, there is the process of customary laws recognised by the government, empowering the local communities to enjoy several CPRs. For instance, the Indian National Forest Policy document of 1988 clearly recognises the rights and concessions to tribal’s and locals regarding grazing lands, collection of non-timber forest products (NTFP), etc. The third type of CPR institutions emerges whenever the market mechanism fails to manage and maintain, or failure on the part of the state to 'police' public resources. One good example is the emergence of village protection committees under joint forest management (JFM) institutions.