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The Calhoun Mouse Utopia Experiment and What it Revealed Was Shocking

What was The Calhoun Mouse Utopia Experiment?

calhoun mouse utopia experiment

The Calhoun mouse utopia experiment is a scientific experiment that tries to figure out what would happen if you take a small mouse and give it a lot of freedom. It is an interesting experiment because it makes you look at the human-animal relationship in a different way. You can also see the parallels to the Industrial Revolution.


In the late 1960s, John B. Calhoun set out to study how rodents’ behavior changes with overcrowding. His research revealed that overpopulated environments could lead to social breakdown. He named this a “behavioral sink,” or a societal collapse.

Calhoun’s study involved hundreds of mice, each living in a nine-square-foot enclosure. It was intended to provide them with a more productive life, and was based on a theory he developed about Norway rats.

After the initial 104 days, the population of the utopia doubled. The adolescent mice were unwilling to fight and refused to attempt to mate. As a result, the females abandoned their young. This was an early sign of the mouse utopia’s impending doom.

By the time the mouse utopia reached its peak, 620 individuals had lived through its first year. However, this was still less than half of the 2,200 individuals that existed when the utopia first started.

Mice’s need for meaningful social roles, a sense of purpose, and an identity are all key aspects of the mouse’s survival. These traits are also present in humans, and it is important to recognize them.

One key element of the mouse’s behavior was the ability to engage in complex behaviors. This included territorial defense, courtship, and maternal care.

Mice were also able to form factions, or gangs, that attacked other groups. Their desire to be the dominant force was also evident. Males who lost dominance fights, such as when their pups died, began to suffer from depression. They no longer had a meaningful place in the society.  This became tragedy in mouse utopia.

Calhoun’s research is often seen as reactionary, but his findings have a spiritual underpinning. His research warns against cosmopolitanism, and urges us to live a more self-sufficient life.

In his book, Animal Populations: Nature Checks and Balances, Calhoun cites the Book of Revelation to a great degree. Despite its pessimistic tone, his book is an intense academic reading experience.

In addition to describing the rodent’s newest craze, Calhoun’s research suggests that our own society is vulnerable to similar developments. We must take steps to prevent our welfare dependent lifestyles from destroying the natural balance of our planet.


The results of Calhoun’s Mouse Utopia experiment are a testament to how social interactions can lead to an increase in population. It is also a warning against cosmopolitanism. And it was a cautionary tale for birth control advocates.

John B Calhoun began his career in behavioral research by studying Norway rats. He soon joined the Rodent Ecology Project in Baltimore. His goal was to find the factors behind the growth and spread of rodent pests in urban areas.

After a decade of research, Calhoun started designing a utopian environment for mice. He chose a quarter-acre pen of Norway rats to house his mice. Each wall was 54 inches high, with sixteen vertical mesh tunnels, four horizontal corridors and a 17-inch-wide, bare wall above.

The first mice nestled in their new environment in 104 days. Social behavior gradually increased. A third of the population grew to be socially dominant. Other groups became aggressive toward trespassers, and some females abandoned their young.

Throughout the first few months, the population was doubled every 55 days. But, by 1970, the growth slowed. When the population reached 80, Calhoun removed new pups.

On Day 315, the first signs of societal collapse appeared. Mice were no longer able to defend their territories. In some territories, infant mortality rose to 90 percent. Females retreated to secluded nesting boxes on the penthouse levels.

Males, however, were engaged in narcissistic introspection. Moreover, the males groomed themselves throughout the day. They were called “the beautiful ones” by Calhoun.

Despite the robust growth, the mouse utopia started to unravel. Several females retreated to secluded spaces and did not breed. Adolescent mice began to refuse to mate and fight.

Ultimately, the mice in the utopia died. Their first death ruined their spirits.

The last thousand mice avoided stressful activities. Those who failed, however, congregated in large numbers. Losers were forced to innovate.

Although the results of Calhoun’s Mouse Utopia were not completely accurate, the study does give us a glimpse of what may be the natural dynamics of a growing population. Ultimately, we must be wary of the influence of our own culture.

Parallels to the Industrial Revolution

Calhoun Mouse Utopia Experiment was a series of experiments designed to study rodent behavior. In his experiments, mice were placed in a new environment. The experiments were intended to identify the factors behind the growth of rodent populations.

Calhoun believed that rodents thrived on their need for survival and social interaction. He also argued that the rise of mouse populations was parallel to the Industrial Revolution.

The first utopian experiment was run in the 1940s, using Norway rats. It was a 4 1/2 foot cube with 256 separate apartments. Each apartment contained an area for the mouse’s food and shelter. However, the mice were unable to survive past weaning.

During the first 104 days, the mice settled in and started nesting. They also began consuming food. As the population increased, the mice began to mark territories.

A few of the mice became aggressive, attacking other mice and young. Some of the males in this group also started to cannibalize the younger rodents. Females, meanwhile, attacked the nursing infants.

The second stage of death was more apocalyptic. Some of the mice were “the beautiful ones” – a term that was coined by Dr. Calhoun. These mice were the social elite and were characterized by perfected appearances. Unlike the other mice, the beautiful ones never engaged in sex. Their time was spent grooming, eating and sleeping.

Calhoun’s research was interpreted as an apocalyptic warning. But it also drew parallels to the rise of modern urban society. Many people were concerned about the increasing deviancy of contemporary societies. Architects and civil engineers were also in vigorous debates about how to build better cities.

While the experiments were a fascinating and provocative look at the behaviors of mice, their applications outside of the laboratory may be limited. Rather, they are a reminder that concern for others is essential to human survival.

Although critics of Calhoun’s work cluster on the conservative end of the political spectrum, many self-styled progressives have weighed in. Some of their theories revolve around the idea that mice are a harbinger of wealth inequality. Others argue that mice are a cautionary tale against welfare dependency.


In the 1960s, John B. Calhoun conceived and conducted an experiment to determine the effect of overcrowding on animal societies. He called it the mouse utopia. It was a 2.7-meter-squared enclosure, filled with 256 apartments for mice and 16 tunnels leading to water. Each pen contained a captive mouse pair, and Calhoun ensured there would be no predators.

When Calhoun began his experiments, there were four pairs of mice. The first generation of mice was hypersexual and hyperactive. Male mice no longer protected their territory or raised young. They spent days mindlessly eating and fighting among themselves.

By Day 315, the males no longer cared for their young or guarded their territories. Females abandoned their young. All of this reflected the unrest of the 1960s.

Eventually, no one was left. Mice no longer had a sense of purpose or identity. Some of them acted as attackers, others as victims. A third of the population became socially dominant. And a final thousand mice focused their attention on themselves.

When the mice died, they entered two stages of death. First, they were referred to as the beautiful ones. These were mice with perfected appearances. Their life was devoted to grooming, sleeping and eating. As a result, they did not engage in mating or conflict.

The second stage was the actual death. The last of the “beautiful ones” were no longer mice. Despite their perfected appearances, they were empty husks.

The apocalypse of the mouse utopia came crashing down because of a series of behavioral sinks. Losers were forced to innovate in order to survive.

In addition to the death of the mice, the mouse utopia was doomed by a collapse in population. The new generation of mice did not have a sense of purpose. This may have reflected the natural dynamics of population growth.

Calhoun’s experiments show that overcrowding causes behavior problems. Ultimately, Calhoun’s research indicates that rodents who are better able to handle their social environment do fare better. Nevertheless, his work remains a touchstone of a pessimistic worldview. Similarly, similar experiments have been conducted in prisons.

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