Spraying DDT in small quantities once had remarkable success. Insects, however, have notoriously short reproductive cycles. This allows micro-evolution to quickly reduce the usefulness of DDT and other pesticides. Thus, in a very, very short period of time, increasing dosages were required to achieve constant results. The pesticide-resistant bugs reflect a commons logic.
Any farmer can benefit in the short term from spraying.
But pesticides eventually create super-pests. This divergence in interests, between the individual and society, is the key to the tragedy of the commons. Bio-engineering increasingly poses another example of a new commons. Genetically altered crops like corn and cotton have been bred with resistance to pests, a resistance that could save farmers billions of dollars in crop losses each year. It remains to be seen if the science of behavioral ecology and the restraint of farmers are sufficient to avert another potential tragedy.