Behavioral sink
behavioral sink is a term invented by ethologist John B. Calhoun to describe a collapse in behavior that can result from overpopulation. The term and concept derive from a series of over-population experiments Calhoun conducted on Norway rats between 1958 and 1962.
In the experiments, Calhoun and his researchers created a series of “rat utopias” – enclosed spaces where rats were given unlimited access to food and water, enabling unfettered population growth. Calhoun coined the term behavioral sink in a February 1, 1962, Scientific American article titled “Population Density and Social Pathology”. He would later perform similar experiments on mice from 1968 to 1972.
Calhoun’s work became used as an animal model of societal collapse, and his study has become a touchstone of urban sociology and psychology in general.
