The Experiment Setup: Calhoun created a 'mouse utopia' with unlimited food, water, and bedding for the rodents, predicting that the population would grow exponentially until overcrowding occurred.

Behavioral Sink: The term 'behavioral sink' was coined from this experiment, describing the collapse in social behaviors and the rise in aggression, social withdrawal, and reproductive issues as the population density increased.

Parallels to Human Society: Calhoun's findings suggested that similar patterns could emerge in human societies as urban populations grow and social structures become strained, leading to potential societal breakdown.