Amongst the Rats and the Extinction of the Population

What if everything needed to live were available—food, shelter, no disease? Would we live happily? Would we multiply?

Core research findings from John B. Calhoun’s work on Population Density and Social Pathology (often referred to through his “Behavioral Sink” experiments) makes us think about life, is life about survival or more?

John B. Calhoun’s experiment was about what happens to social behaviour when population density becomes very high, even when basic needs are fully met.

In simple terms:

Calhoun wanted to understand this question: If food, water, and shelter are not a problem, can overcrowding alone damage a society?

What he did

He created enclosed environments for rats and mice.

Food, water, and nesting material were unlimited.

There were no predators or diseases introduced.

The only limiting factor was space.

These setups were later called “rat utopias” or “Universe” experiments.

What he observed

As the population increased, social order began to break down.

Normal behaviours like mating, parenting, and cooperation deteriorated.

Aggression increased in some, while others withdrew completely.

Maternal care collapsed, leading to high infant mortality.

Eventually, reproduction stopped altogether.

What the experiment showed

Survival is not only about resources.

Social structure, roles, and space for meaningful interaction are essential.

Overcrowding can lead to psychological and social collapse even in “ideal” physical conditions.

So, what is our “utopia”?

Speed in life, careers, property, money? As we move towards hyper-urbanisation, where more becomes less, what happens to us and our children? An overload of stimuli.

Our children grow amidst crowds, constant noise, rigid schedules, social conventions, and endless “must-haves.”

What are the trade-offs? What moves the individual and the collective? The trade-off is simple: the loss of meaningful experiences and a sense of belonging.

Children need more than “exposure.” They need to be heard. They need real experiences, not templatized workshops or expert-driven knowledge. When everything becomes transactional—schedules, outcomes, compliance, performance—children withdraw.

Children are not moved through systems; they grow within communities. Parents are not “adults who know all of life,” but partners in inquiry.

Calhoun’s work is not a warning against cities. It is a reminder that human beings require social meaning, not just physical space.

In crowded environments (too much of everything) when relationships become anonymous and responsibility is diffused, even if resources are abundant, we struggle with our roles:

“We don’t know what to do.”

“Our children do not listen to us.”

These are signs of withdrawal in children.

Is there something beyond survival and growth?