<Li> Uncontrolled human population growth leading to overpopulation . </Li> <Li> A preference for sons made people abort foetal girls . This results in an imbalanced gender ratio . </Li> <Li> Air, whether ambient air polluted by industrial emissions and cars among other sources of air pollution, or indoor air </Li> <Li> Water--Water pollution, water crisis of over-extraction of groundwater and wasting water due to overirrigation </Li>

The tragedy of the commons is a phenomenon that occurs only when the number of users is small