The tragedy of the commons in evolutionary biology

Garrett Hardin's tragedy of the commons is an analogy that shows how individuals driven by self-interest can end up destroying the resource upon which they all depend. The proposed solutions for humans rely on highly advanced skills such as negotiation, which raises the question of how non-human organisms manage to resolve similar tragedies. In recent years, this question has promoted evolutionary biologists to apply the tragedy of the commons to a wide range of biological systems. Here, we provide tools to categorize different types of tragedy and review different mechanisms, including kinship, policing and diminishing returns that can resolve conflicts that could otherwise end in tragedy. A central open question, however, is how often biological systems are able to resolve these scenarios rather than drive themselves extinct through individual-level selection favouring self-interested behaviours. Garrett Hardin's tragedy of the commons is an analogy that shows how individuals driven by self-interest can end up destroying the resource upon which they all depend. The proposed solutions for humans rely on highly advanced skills such as negotiation, which raises the question of how non-human organisms manage to resolve similar tragedies. In recent years, this question has promoted evolutionary biologists to apply the tragedy of the commons to a wide range of biological systems. Here, we provide tools to categorize different types of tragedy and review different mechanisms, including kinship, policing and diminishing returns that can resolve conflicts that could otherwise end in tragedy. A central open question, however, is how often biological systems are able to resolve these scenarios rather than drive themselves extinct through individual-level selection favouring self-interested behaviours. an individual that gains a benefit from the collective, without investing in the collective itself. These individuals can also be called ’free-riders’. a situation in which selfish competition or free-riding escalates until the resource is fully depleted. This can cause the collapse of the entire population (i.e. extinction) if the resource was essential. a tragedy of the commons in which escalated competition stops before a collapse is reached. the act of individuals paying an individual cost to contribute to a collective benefit. selection acting at the level of the individual, to favour individuals or genes that maximise their own fitness. the depletion of a resource beyond the point at which sustainable use is possible. the overall benefits and costs gained from a particular strategy or behaviour. a common resource that benefits all individuals in a group. the absence of a tragedy of the commons. That is, a situation in which inherent conflict causes no group-level costs. a public good that is shared by all members of a population or group and is specifically created by cooperating individuals. selection that arises by differential extinction of species. a situation in which individual competition reduces the resource over which individuals compete, resulting in lower overall fitness for all members of a group or population. a situation in which one individual's gain is matched by other individuals’ loss. Cutting a cake and chess are both examples of zero-sum games.